Add transactional helper methods to DbViewModel.

and get rid of ThreadList controllers

.idea/runConfigurations/BridgeTest.xml

@@ -1,24 +0,0 @@
-<component name="ProjectRunConfigurationManager">
-  <configuration default="false" name="BridgeTest" type="AndroidJUnit" factoryName="Android JUnit" nameIsGenerated="true">
-    <module name="briar.bramble-java" />
-    <useClassPathOnly />
-    <extension name="coverage">
-      <pattern>
-        <option name="PATTERN" value="org.briarproject.bramble.plugin.tor.*" />
-        <option name="ENABLED" value="true" />
-      </pattern>
-    </extension>
-    <option name="PACKAGE_NAME" value="org.briarproject.bramble.plugin.tor" />
-    <option name="MAIN_CLASS_NAME" value="org.briarproject.bramble.plugin.tor.BridgeTest" />
-    <option name="METHOD_NAME" value="" />
-    <option name="TEST_OBJECT" value="class" />
-    <option name="PARAMETERS" value="" />
-    <option name="WORKING_DIRECTORY" value="$MODULE_DIR$" />
-    <envs>
-      <env name="OPTIONAL_TESTS" value="org.briarproject.bramble.plugin.tor.BridgeTest" />
-    </envs>
-    <method v="2">
-      <option name="Android.Gradle.BeforeRunTask" enabled="true" />
-    </method>
-  </configuration>
-</component>

bramble-android/build.gradle

@@ -11,8 +11,8 @@ android {
 	defaultConfig {
 		minSdkVersion 16
 		targetSdkVersion 29
-		versionCode 10214
-		versionName "1.2.14"
+		versionCode 10213
+		versionName "1.2.13"
 		consumerProguardFiles 'proguard-rules.txt'
 
 		testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"

bramble-api/src/main/java/org/briarproject/bramble/api/ThrowingRunnable.java

@@ -0,0 +1,6 @@
+package org.briarproject.bramble.api;
+
+public interface ThrowingRunnable<T extends Throwable> {
+
+	void run() throws T;
+}

bramble-core/src/main/java/org/briarproject/bramble/sync/DuplexOutgoingSession.java

@@ -1,5 +1,6 @@
 package org.briarproject.bramble.sync;
 
+import org.briarproject.bramble.api.ThrowingRunnable;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.contact.event.ContactRemovedEvent;
 import org.briarproject.bramble.api.db.DatabaseComponent;

bramble-core/src/main/java/org/briarproject/bramble/sync/SimplexOutgoingSession.java

@@ -1,5 +1,6 @@
 package org.briarproject.bramble.sync;
 
+import org.briarproject.bramble.api.ThrowingRunnable;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.contact.event.ContactRemovedEvent;
 import org.briarproject.bramble.api.db.DatabaseComponent;

bramble-core/src/main/java/org/briarproject/bramble/sync/ThrowingRunnable.java

@@ -1,6 +0,0 @@
-package org.briarproject.bramble.sync;
-
-interface ThrowingRunnable<T extends Throwable> {
-
-	void run() throws T;
-}

bramble-core/src/main/resources/bridges

@@ -1,14 +1,5 @@
-Bridge obfs4 192.95.36.142:443 CDF2E852BF539B82BD10E27E9115A31734E378C2 cert=qUVQ0srL1JI/vO6V6m/24anYXiJD3QP2HgzUKQtQ7GRqqUvs7P+tG43RtAqdhLOALP7DJQ iat-mode=1
-Bridge obfs4 38.229.1.78:80 C8CBDB2464FC9804A69531437BCF2BE31FDD2EE4 cert=Hmyfd2ev46gGY7NoVxA9ngrPF2zCZtzskRTzoWXbxNkzeVnGFPWmrTtILRyqCTjHR+s9dg iat-mode=1
-Bridge obfs4 37.218.245.14:38224 D9A82D2F9C2F65A18407B1D2B764F130847F8B5D cert=bjRaMrr1BRiAW8IE9U5z27fQaYgOhX1UCmOpg2pFpoMvo6ZgQMzLsaTzzQNTlm7hNcb+Sg iat-mode=0
-Bridge obfs4 85.31.186.98:443 011F2599C0E9B27EE74B353155E244813763C3E5 cert=ayq0XzCwhpdysn5o0EyDUbmSOx3X/oTEbzDMvczHOdBJKlvIdHHLJGkZARtT4dcBFArPPg iat-mode=0
-Bridge obfs4 85.31.186.26:443 91A6354697E6B02A386312F68D82CF86824D3606 cert=PBwr+S8JTVZo6MPdHnkTwXJPILWADLqfMGoVvhZClMq/Urndyd42BwX9YFJHZnBB3H0XCw iat-mode=0
-Bridge obfs4 193.11.166.194:27015 2D82C2E354D531A68469ADF7F878FA6060C6BACA cert=4TLQPJrTSaDffMK7Nbao6LC7G9OW/NHkUwIdjLSS3KYf0Nv4/nQiiI8dY2TcsQx01NniOg iat-mode=0
-Bridge obfs4 193.11.166.194:27020 86AC7B8D430DAC4117E9F42C9EAED18133863AAF cert=0LDeJH4JzMDtkJJrFphJCiPqKx7loozKN7VNfuukMGfHO0Z8OGdzHVkhVAOfo1mUdv9cMg iat-mode=0
-Bridge obfs4 193.11.166.194:27025 1AE2C08904527FEA90C4C4F8C1083EA59FBC6FAF cert=ItvYZzW5tn6v3G4UnQa6Qz04Npro6e81AP70YujmK/KXwDFPTs3aHXcHp4n8Vt6w/bv8cA iat-mode=0
-Bridge obfs4 209.148.46.65:443 74FAD13168806246602538555B5521A0383A1875 cert=ssH+9rP8dG2NLDN2XuFw63hIO/9MNNinLmxQDpVa+7kTOa9/m+tGWT1SmSYpQ9uTBGa6Hw iat-mode=0
-Bridge obfs4 146.57.248.225:22 10A6CD36A537FCE513A322361547444B393989F0 cert=K1gDtDAIcUfeLqbstggjIw2rtgIKqdIhUlHp82XRqNSq/mtAjp1BIC9vHKJ2FAEpGssTPw iat-mode=0
-Bridge obfs4 45.145.95.6:27015 C5B7CD6946FF10C5B3E89691A7D3F2C122D2117C cert=TD7PbUO0/0k6xYHMPW3vJxICfkMZNdkRrb63Zhl5j9dW3iRGiCx0A7mPhe5T2EDzQ35+Zw iat-mode=0
-Bridge obfs4 51.222.13.177:80 5EDAC3B810E12B01F6FD8050D2FD3E277B289A08 cert=2uplIpLQ0q9+0qMFrK5pkaYRDOe460LL9WHBvatgkuRr/SL31wBOEupaMMJ6koRE6Ld0ew iat-mode=0
 Bridge obfs4 78.46.188.239:37356 5A2D2F4158D0453E00C7C176978D3F41D69C45DB cert=3c0SwxpOisbohNxEc4tb875RVW8eOu1opRTVXJhafaKA/PNNtI7ElQIVOVZg1AdL5bxGCw iat-mode=0
-Bridge meek_lite 192.0.2.2:2 97700DFE9F483596DDA6264C4D7DF7641E1E39CE url=https://meek.azureedge.net/ front=ajax.aspnetcdn.com
+Bridge obfs4 52.15.78.72:9443 02069A3C5362476936B62BA6F5ACC41ABD573A9B cert=ijYG/OKc7kqu2YzKNFfeXN7/BG2BOgfEP2KyYEiGDQthnHbsOiTWHeIG0WJVW+BckzDgKw iat-mode=0
+Bridge obfs4 13.58.29.242:9443 0C58939A77DA6B6B29D4B5236A75865659607AE0 cert=OylWIEHb/ezpq1zWxW0sgKRn+9ARH2eOcQOZ8/Gew+4l+oKOhQ2jUX/Y+FSl61JorXZUWA iat-mode=0
+Bridge obfs4 45.33.37.112:9443 60A609BB4ABE8D46E634AE81ED29ADAB7776B399 cert=t5v19WmNv5Sc2YPNr8RQids365W7MY8zJwQVkOxBjUMFomMWARDzsbYpcWLLcw0J9Gm+BQ iat-mode=0
+Bridge meek_lite 0.0.2.0:2 97700DFE9F483596DDA6264C4D7DF7641E1E39CE url=https://meek.azureedge.net/ front=ajax.aspnetcdn.com

briar-android/artwork/notification_signout.svg

@@ -1 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd"><svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" version="1.1" width="24" height="24" viewBox="0 0 24 24"><path d="M16,17V14H9V10H16V7L21,12L16,17M14,2A2,2 0 0,1 16,4V6H14V4H5V20H14V18H16V20A2,2 0 0,1 14,22H5A2,2 0 0,1 3,20V4A2,2 0 0,1 5,2H14Z" /></svg>

briar-android/build.gradle

@@ -22,11 +22,9 @@ android {
 	defaultConfig {
 		minSdkVersion 16
 		targetSdkVersion 29
-		versionCode 10214
-		versionName "1.2.14"
+		versionCode 10213
+		versionName "1.2.13"
 		applicationId "org.briarproject.briar.android"
-
-		vectorDrawables.useSupportLibrary = true
 		buildConfigField "String", "GitHash",
 				"\"${getStdout(['git', 'rev-parse', '--short=7', 'HEAD'], 'No commit hash')}\""
 		def now = (long) (System.currentTimeMillis() / 1000)

briar-android/src/main/java/org/briarproject/briar/android/AndroidNotificationManagerImpl.java

@@ -255,7 +255,7 @@ class AndroidNotificationManagerImpl implements AndroidNotificationManager,
 				R.string.ongoing_notification_title;
 		int text = locked ? R.string.lock_tap_to_unlock :
 				R.string.ongoing_notification_text;
-		int icon = locked ? R.drawable.notification_lock :
+		int icon = locked ? R.drawable.startup_lock :
 				R.drawable.notification_ongoing;
 		// Ongoing foreground notification that shows BriarService is running
 		NotificationCompat.Builder b =
@@ -624,7 +624,7 @@ class AndroidNotificationManagerImpl implements AndroidNotificationManager,
 
 		NotificationCompat.Builder b =
 				new NotificationCompat.Builder(appContext, REMINDER_CHANNEL_ID);
-		b.setSmallIcon(R.drawable.notification_signout);
+		b.setSmallIcon(R.drawable.ic_signout);
 		b.setColor(getColor(appContext, R.color.briar_primary));
 		b.setContentTitle(
 				appContext.getText(R.string.reminder_notification_title));

briar-android/src/main/java/org/briarproject/briar/android/AppModule.java

@@ -35,9 +35,11 @@ import org.briarproject.briar.android.forum.ForumModule;
 import org.briarproject.briar.android.keyagreement.ContactExchangeModule;
 import org.briarproject.briar.android.login.LoginModule;
 import org.briarproject.briar.android.navdrawer.NavDrawerModule;
+import org.briarproject.briar.android.privategroup.conversation.GroupConversationModule;
 import org.briarproject.briar.android.settings.SettingsModule;
 import org.briarproject.briar.android.privategroup.list.GroupListModule;
 import org.briarproject.briar.android.reporting.DevReportModule;
+import org.briarproject.briar.android.sharing.SharingModule;
 import org.briarproject.briar.android.test.TestAvatarCreatorImpl;
 import org.briarproject.briar.android.viewmodel.ViewModelModule;
 import org.briarproject.briar.api.android.AndroidNotificationManager;
@@ -79,8 +81,10 @@ import static org.briarproject.briar.android.TestingConstants.IS_DEBUG_BUILD;
 		DevReportModule.class,
 		ContactListModule.class,
 		// below need to be within same scope as ViewModelProvider.Factory
-		ForumModule.BindsModule.class,
+		ForumModule.class,
 		GroupListModule.class,
+		GroupConversationModule.class,
+		SharingModule.class,
 })
 public class AppModule {
 

briar-android/src/main/java/org/briarproject/briar/android/activity/ActivityComponent.java

@@ -32,7 +32,6 @@ import org.briarproject.briar.android.conversation.ImageFragment;
 import org.briarproject.briar.android.forum.CreateForumActivity;
 import org.briarproject.briar.android.forum.ForumActivity;
 import org.briarproject.briar.android.forum.ForumListFragment;
-import org.briarproject.briar.android.forum.ForumModule;
 import org.briarproject.briar.android.fragment.ScreenFilterDialogFragment;
 import org.briarproject.briar.android.introduction.ContactChooserFragment;
 import org.briarproject.briar.android.introduction.IntroductionActivity;
@@ -50,7 +49,6 @@ import org.briarproject.briar.android.navdrawer.TransportsActivity;
 import org.briarproject.briar.android.panic.PanicPreferencesActivity;
 import org.briarproject.briar.android.panic.PanicResponderActivity;
 import org.briarproject.briar.android.privategroup.conversation.GroupActivity;
-import org.briarproject.briar.android.privategroup.conversation.GroupConversationModule;
 import org.briarproject.briar.android.privategroup.creation.CreateGroupActivity;
 import org.briarproject.briar.android.privategroup.creation.CreateGroupFragment;
 import org.briarproject.briar.android.privategroup.creation.CreateGroupModule;
@@ -89,12 +87,10 @@ import dagger.Component;
 		ActivityModule.class,
 		BlogModule.class,
 		CreateGroupModule.class,
-		ForumModule.class,
 		GroupInvitationModule.class,
-		GroupConversationModule.class,
 		GroupMemberModule.class,
 		GroupRevealModule.class,
-		SharingModule.class
+		SharingModule.SharingLegacyModule.class
 }, dependencies = AndroidComponent.class)
 public interface ActivityComponent {
 

briar-android/src/main/java/org/briarproject/briar/android/activity/BaseActivity.java

@@ -14,7 +14,6 @@ import org.briarproject.briar.android.BriarApplication;
 import org.briarproject.briar.android.DestroyableContext;
 import org.briarproject.briar.android.Localizer;
 import org.briarproject.briar.android.controller.ActivityLifecycleController;
-import org.briarproject.briar.android.forum.ForumModule;
 import org.briarproject.briar.android.fragment.BaseFragment;
 import org.briarproject.briar.android.fragment.ScreenFilterDialogFragment;
 import org.briarproject.briar.android.util.UiUtils;
@@ -87,7 +86,6 @@ public abstract class BaseActivity extends AppCompatActivity
 		activityComponent = DaggerActivityComponent.builder()
 				.androidComponent(applicationComponent)
 				.activityModule(getActivityModule())
-				.forumModule(getForumModule())
 				.build();
 		injectActivity(activityComponent);
 		super.onCreate(state);
@@ -122,11 +120,6 @@ public abstract class BaseActivity extends AppCompatActivity
 		return new ActivityModule(this);
 	}
 
-	// TODO use a test module where this is used in tests
-	protected ForumModule getForumModule() {
-		return new ForumModule();
-	}
-
 	@Override
 	protected void onStart() {
 		super.onStart();

briar-android/src/main/java/org/briarproject/briar/android/activity/BriarActivity.java

@@ -160,7 +160,6 @@ public abstract class BriarActivity extends BaseActivity {
 	 * @param ownLayout true if the custom toolbar brings its own layout
 	 * @return the Toolbar object or null if content view did not contain one
 	 */
-	@Nullable
 	protected Toolbar setUpCustomToolbar(boolean ownLayout) {
 		// Custom Toolbar
 		Toolbar toolbar = findViewById(R.id.toolbar);

briar-android/src/main/java/org/briarproject/briar/android/contact/ContactListViewModel.java

@@ -45,10 +45,8 @@ import androidx.arch.core.util.Function;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.MutableLiveData;
 
-import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
 import static org.briarproject.bramble.util.LogUtils.logDuration;
-import static org.briarproject.bramble.util.LogUtils.logException;
 import static org.briarproject.bramble.util.LogUtils.now;
 
 @NotNullByDefault
@@ -173,14 +171,9 @@ class ContactListViewModel extends DbViewModel implements EventListener {
 	}
 
 	void checkForPendingContacts() {
-		runOnDbThread(() -> {
-			try {
-				boolean hasPending =
-						!contactManager.getPendingContacts().isEmpty();
-				hasPendingContacts.postValue(hasPending);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
+		runOnDbThreadOrLogException(() -> {
+			boolean hasPending = !contactManager.getPendingContacts().isEmpty();
+			hasPendingContacts.postValue(hasPending);
 		});
 	}
 

briar-android/src/main/java/org/briarproject/briar/android/contact/add/remote/AddContactViewModel.java

@@ -2,12 +2,9 @@ package org.briarproject.briar.android.contact.add.remote;
 
 import android.app.Application;
 
-import org.briarproject.bramble.api.FormatException;
-import org.briarproject.bramble.api.UnsupportedVersionException;
 import org.briarproject.bramble.api.contact.ContactManager;
 import org.briarproject.bramble.api.contact.PendingContact;
 import org.briarproject.bramble.api.db.DatabaseExecutor;
-import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.NoSuchPendingContactException;
 import org.briarproject.bramble.api.db.TransactionManager;
 import org.briarproject.bramble.api.lifecycle.LifecycleManager;
@@ -18,7 +15,6 @@ import org.briarproject.briar.android.viewmodel.LiveEvent;
 import org.briarproject.briar.android.viewmodel.LiveResult;
 import org.briarproject.briar.android.viewmodel.MutableLiveEvent;
 
-import java.security.GeneralSecurityException;
 import java.util.concurrent.Executor;
 import java.util.logging.Logger;
 
@@ -66,15 +62,10 @@ public class AddContactViewModel extends DbViewModel {
 	}
 
 	private void loadHandshakeLink() {
-		runOnDbThread(() -> {
-			try {
-				handshakeLink.postValue(contactManager.getHandshakeLink());
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				// the UI should stay disabled in this case,
-				// leaving the user unable to proceed
-			}
-		});
+		// If an exception is thrown the UI should stay disabled,
+		// leaving the user unable to proceed
+		runOnDbThreadOrLogException(() ->
+				handshakeLink.postValue(contactManager.getHandshakeLink()));
 	}
 
 	LiveData<String> getHandshakeLink() {
@@ -106,17 +97,11 @@ public class AddContactViewModel extends DbViewModel {
 	void addContact(String nickname) {
 		if (remoteHandshakeLink == null) throw new IllegalStateException();
 		runOnDbThread(() -> {
-			try {
-				contactManager.addPendingContact(remoteHandshakeLink, nickname);
-				addContactResult.postValue(new LiveResult<>(true));
-			} catch (UnsupportedVersionException e) {
-				logException(LOG, WARNING, e);
-				addContactResult.postValue(new LiveResult<>(e));
-			} catch (DbException | FormatException
-					| GeneralSecurityException e) {
-				logException(LOG, WARNING, e);
-				addContactResult.postValue(new LiveResult<>(e));
-			}
+			contactManager.addPendingContact(remoteHandshakeLink, nickname);
+			addContactResult.postValue(new LiveResult<>(true));
+		}, e -> {
+			logException(LOG, WARNING, e);
+			addContactResult.postValue(new LiveResult<>(e));
 		});
 	}
 
@@ -126,13 +111,13 @@ public class AddContactViewModel extends DbViewModel {
 
 	public void updatePendingContact(String name, PendingContact p) {
 		runOnDbThread(() -> {
-			try {
-				contactManager.removePendingContact(p.getId());
-				addContact(name);
-			} catch (NoSuchPendingContactException e) {
+			contactManager.removePendingContact(p.getId());
+			addContact(name);
+		}, e -> {
+			if (e instanceof NoSuchPendingContactException) {
 				logException(LOG, WARNING, e);
 				// no error in UI as pending contact was converted into contact
-			} catch (DbException e) {
+			} else {
 				logException(LOG, WARNING, e);
 				addContactResult.postValue(new LiveResult<>(e));
 			}

briar-android/src/main/java/org/briarproject/briar/android/contact/add/remote/PendingContactListViewModel.java

@@ -10,7 +10,6 @@ import org.briarproject.bramble.api.contact.PendingContactState;
 import org.briarproject.bramble.api.contact.event.PendingContactRemovedEvent;
 import org.briarproject.bramble.api.contact.event.PendingContactStateChangedEvent;
 import org.briarproject.bramble.api.db.DatabaseExecutor;
-import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.TransactionManager;
 import org.briarproject.bramble.api.event.Event;
 import org.briarproject.bramble.api.event.EventBus;
@@ -33,10 +32,8 @@ import javax.inject.Inject;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.MutableLiveData;
 
-import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
 import static org.briarproject.bramble.api.contact.PendingContactState.OFFLINE;
-import static org.briarproject.bramble.util.LogUtils.logException;
 
 @NotNullByDefault
 public class PendingContactListViewModel extends DbViewModel
@@ -90,24 +87,20 @@ public class PendingContactListViewModel extends DbViewModel
 	}
 
 	private void loadPendingContacts() {
-		runOnDbThread(() -> {
-			try {
-				Collection<Pair<PendingContact, PendingContactState>> pairs =
-						contactManager.getPendingContacts();
-				List<PendingContactItem> items = new ArrayList<>(pairs.size());
-				boolean online = pairs.isEmpty();
-				for (Pair<PendingContact, PendingContactState> pair : pairs) {
-					PendingContact p = pair.getFirst();
-					PendingContactState state = pair.getSecond();
-					long lastPoll = rendezvousPoller.getLastPollTime(p.getId());
-					items.add(new PendingContactItem(p, state, lastPoll));
-					online = online || state != OFFLINE;
-				}
-				pendingContacts.postValue(items);
-				hasInternetConnection.postValue(online);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
+		runOnDbThreadOrLogException(() -> {
+			Collection<Pair<PendingContact, PendingContactState>> pairs =
+					contactManager.getPendingContacts();
+			List<PendingContactItem> items = new ArrayList<>(pairs.size());
+			boolean online = pairs.isEmpty();
+			for (Pair<PendingContact, PendingContactState> pair : pairs) {
+				PendingContact p = pair.getFirst();
+				PendingContactState state = pair.getSecond();
+				long lastPoll = rendezvousPoller.getLastPollTime(p.getId());
+				items.add(new PendingContactItem(p, state, lastPoll));
+				online = online || state != OFFLINE;
 			}
+			pendingContacts.postValue(items);
+			hasInternetConnection.postValue(online);
 		});
 	}
 
@@ -116,13 +109,8 @@ public class PendingContactListViewModel extends DbViewModel
 	}
 
 	void removePendingContact(PendingContactId id) {
-		runOnDbThread(() -> {
-			try {
-				contactManager.removePendingContact(id);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
-		});
+		runOnDbThreadOrLogException(() ->
+				contactManager.removePendingContact(id));
 	}
 
 	LiveData<Boolean> getHasInternetConnection() {

briar-android/src/main/java/org/briarproject/briar/android/controller/SharingController.java

@@ -7,6 +7,7 @@ import java.util.Collection;
 
 import androidx.annotation.UiThread;
 
+@Deprecated
 @NotNullByDefault
 public interface SharingController {
 

briar-android/src/main/java/org/briarproject/briar/android/controller/SharingControllerImpl.java

@@ -18,6 +18,7 @@ import javax.inject.Inject;
 
 import androidx.annotation.UiThread;
 
+@Deprecated
 @NotNullByDefault
 public class SharingControllerImpl implements SharingController, EventListener {
 

briar-android/src/main/java/org/briarproject/briar/android/conversation/ConversationActivity.java

@@ -3,7 +3,6 @@ package org.briarproject.briar.android.conversation;
 import android.annotation.SuppressLint;
 import android.content.DialogInterface;
 import android.content.Intent;
-import android.graphics.drawable.Drawable;
 import android.os.Bundle;
 import android.os.Parcelable;
 import android.transition.Slide;
@@ -106,7 +105,6 @@ import androidx.recyclerview.selection.SelectionTracker.SelectionObserver;
 import androidx.recyclerview.selection.StorageStrategy;
 import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
-import androidx.vectordrawable.graphics.drawable.VectorDrawableCompat;
 import de.hdodenhof.circleimageview.CircleImageView;
 import uk.co.samuelwall.materialtaptargetprompt.MaterialTapTargetPrompt;
 
@@ -481,10 +479,12 @@ public class ConversationActivity extends BriarActivity
 	@UiThread
 	private void displayContactOnlineStatus() {
 		if (connectionRegistry.isConnected(contactId)) {
-			toolbarStatus.setImageResource(R.drawable.contact_online);
+			toolbarStatus.setImageDrawable(ContextCompat.getDrawable(
+					ConversationActivity.this, R.drawable.contact_online));
 			toolbarStatus.setContentDescription(getString(R.string.online));
 		} else {
-			toolbarStatus.setImageResource(R.drawable.contact_offline);
+			toolbarStatus.setImageDrawable(ContextCompat.getDrawable(
+					ConversationActivity.this, R.drawable.contact_offline));
 			toolbarStatus.setContentDescription(getString(R.string.offline));
 		}
 	}
@@ -935,16 +935,13 @@ public class ConversationActivity extends BriarActivity
 			return;
 		}
 
-		int color =
-				ContextCompat.getColor(this, R.color.briar_primary);
-		Drawable drawable = VectorDrawableCompat
-				.create(getResources(), R.drawable.ic_more_vert_accent, null);
 		new MaterialTapTargetPrompt.Builder(ConversationActivity.this,
 				R.style.OnboardingDialogTheme).setTarget(target)
 				.setPrimaryText(R.string.introduction_onboarding_title)
 				.setSecondaryText(R.string.introduction_onboarding_text)
-				.setIconDrawable(drawable)
-				.setBackgroundColour(color)
+				.setIcon(R.drawable.ic_more_vert_accent)
+				.setBackgroundColour(
+						ContextCompat.getColor(this, R.color.briar_primary))
 				.show();
 	}
 

briar-android/src/main/java/org/briarproject/briar/android/conversation/ConversationViewModel.java

@@ -149,7 +149,7 @@ public class ConversationViewModel extends DbViewModel
 			AttachmentReceivedEvent a = (AttachmentReceivedEvent) e;
 			if (a.getContactId().equals(contactId)) {
 				LOG.info("Attachment received");
-				runOnDbThread(() -> attachmentRetriever
+				runOnDbThreadOrLogException(() -> attachmentRetriever
 						.loadAttachmentItem(a.getMessageId()));
 			}
 		} else if (e instanceof AvatarUpdatedEvent) {
@@ -194,44 +194,36 @@ public class ConversationViewModel extends DbViewModel
 
 	private void loadContact(ContactId contactId) {
 		runOnDbThread(() -> {
-			try {
-				long start = now();
-				Contact c = contactManager.getContact(contactId);
-				AuthorInfo authorInfo = authorManager.getAuthorInfo(c);
-				contactItem.postValue(new ContactItem(c, authorInfo));
-				logDuration(LOG, "Loading contact", start);
-				start = now();
-				checkFeaturesAndOnboarding(contactId);
-				logDuration(LOG, "Checking for image support", start);
-			} catch (NoSuchContactException e) {
+			long start = now();
+			Contact c = contactManager.getContact(contactId);
+			AuthorInfo authorInfo = authorManager.getAuthorInfo(c);
+			contactItem.postValue(new ContactItem(c, authorInfo));
+			logDuration(LOG, "Loading contact", start);
+			start = now();
+			checkFeaturesAndOnboarding(contactId);
+			logDuration(LOG, "Checking for image support", start);
+		}, e -> {
+			if (e instanceof NoSuchContactException) {
 				contactDeleted.postValue(true);
-			} catch (DbException e) {
+			} else {
 				logException(LOG, WARNING, e);
 			}
 		});
 	}
 
 	void markMessageRead(GroupId g, MessageId m) {
-		runOnDbThread(() -> {
-			try {
-				long start = now();
-				messagingManager.setReadFlag(g, m, true);
-				logDuration(LOG, "Marking read", start);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
+		runOnDbThreadOrLogException(() -> {
+			long start = now();
+			messagingManager.setReadFlag(g, m, true);
+			logDuration(LOG, "Marking read", start);
 		});
 	}
 
 	void setContactAlias(String alias) {
-		runOnDbThread(() -> {
-			try {
-				contactManager.setContactAlias(requireNonNull(contactId),
-						alias.isEmpty() ? null : alias);
-				loadContact(contactId);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
+		runOnDbThreadOrLogException(() -> {
+			contactManager.setContactAlias(requireNonNull(contactId),
+					alias.isEmpty() ? null : alias);
+			loadContact(contactId);
 		});
 	}
 
@@ -327,21 +319,17 @@ public class ConversationViewModel extends DbViewModel
 	@UiThread
 	private void storeMessage(PrivateMessage m) {
 		attachmentCreator.onAttachmentsSent(m.getMessage().getId());
-		runOnDbThread(() -> {
-			try {
-				long start = now();
-				messagingManager.addLocalMessage(m);
-				logDuration(LOG, "Storing message", start);
-				Message message = m.getMessage();
-				PrivateMessageHeader h = new PrivateMessageHeader(
-						message.getId(), message.getGroupId(),
-						message.getTimestamp(), true, true, false, false,
-						m.hasText(), m.getAttachmentHeaders());
-				// TODO add text to cache when available here
-				addedHeader.postEvent(h);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
+		runOnDbThreadOrLogException(() -> {
+			long start = now();
+			messagingManager.addLocalMessage(m);
+			logDuration(LOG, "Storing message", start);
+			Message message = m.getMessage();
+			PrivateMessageHeader h = new PrivateMessageHeader(
+					message.getId(), message.getGroupId(),
+					message.getTimestamp(), true, true, false, false,
+					m.hasText(), m.getAttachmentHeaders());
+			// TODO add text to cache when available here
+			addedHeader.postEvent(h);
 		});
 	}
 
@@ -383,12 +371,7 @@ public class ConversationViewModel extends DbViewModel
 
 	@UiThread
 	void recheckFeaturesAndOnboarding(ContactId contactId) {
-		runOnDbThread(() -> {
-			try {
-				checkFeaturesAndOnboarding(contactId);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
-		});
+		runOnDbThreadOrLogException(() ->
+				checkFeaturesAndOnboarding(contactId));
 	}
 }

briar-android/src/main/java/org/briarproject/briar/android/conversation/ImageViewModel.java

@@ -6,7 +6,6 @@ import android.net.Uri;
 import android.view.View;
 
 import org.briarproject.bramble.api.db.DatabaseExecutor;
-import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.TransactionManager;
 import org.briarproject.bramble.api.event.Event;
 import org.briarproject.bramble.api.event.EventBus;
@@ -198,14 +197,12 @@ public class ImageViewModel extends DbViewModel implements EventListener {
 	private void saveImage(AttachmentItem attachment, OutputStreamProvider osp,
 			@Nullable Runnable afterCopy) {
 		runOnDbThread(() -> {
-			try {
-				Attachment a =
-						attachmentReader.getAttachment(attachment.getHeader());
-				copyImageFromDb(a, osp, afterCopy);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				saveState.postEvent(true);
-			}
+			Attachment a =
+					attachmentReader.getAttachment(attachment.getHeader());
+			copyImageFromDb(a, osp, afterCopy);
+		}, e -> {
+			logException(LOG, WARNING, e);
+			saveState.postEvent(true);
 		});
 	}
 

briar-android/src/main/java/org/briarproject/briar/android/forum/ForumActivity.java

@@ -6,52 +6,54 @@ import android.os.Bundle;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
-import android.widget.Toast;
 
-import org.briarproject.bramble.api.contact.ContactId;
-import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
 import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
 import org.briarproject.briar.R;
 import org.briarproject.briar.android.activity.ActivityComponent;
-import org.briarproject.briar.android.controller.handler.UiResultExceptionHandler;
-import org.briarproject.briar.android.forum.ForumController.ForumListener;
 import org.briarproject.briar.android.sharing.ForumSharingStatusActivity;
 import org.briarproject.briar.android.sharing.ShareForumActivity;
 import org.briarproject.briar.android.threaded.ThreadItemAdapter;
 import org.briarproject.briar.android.threaded.ThreadListActivity;
-import org.briarproject.briar.android.threaded.ThreadListController;
-import org.briarproject.briar.api.forum.Forum;
+import org.briarproject.briar.android.threaded.ThreadListViewModel;
 
 import javax.annotation.Nullable;
 import javax.inject.Inject;
 
 import androidx.appcompat.app.AlertDialog;
 import androidx.appcompat.widget.Toolbar;
-import androidx.recyclerview.widget.LinearLayoutManager;
+import androidx.lifecycle.ViewModelProvider;
 
 import static android.content.Intent.FLAG_ACTIVITY_CLEAR_TOP;
-import static android.widget.Toast.LENGTH_SHORT;
 import static org.briarproject.briar.android.activity.RequestCodes.REQUEST_SHARE_FORUM;
+import static org.briarproject.briar.android.util.UiUtils.observeOnce;
 import static org.briarproject.briar.api.forum.ForumConstants.MAX_FORUM_POST_TEXT_LENGTH;
 
 @MethodsNotNullByDefault
 @ParametersNotNullByDefault
 public class ForumActivity extends
-		ThreadListActivity<Forum, ForumPostItem, ThreadItemAdapter<ForumPostItem>>
-		implements ForumListener {
+		ThreadListActivity<ForumPostItem, ThreadItemAdapter<ForumPostItem>> {
 
 	@Inject
-	ForumController forumController;
+	ViewModelProvider.Factory viewModelFactory;
+
+	private ForumViewModel viewModel;
 
 	@Override
 	public void injectActivity(ActivityComponent component) {
 		component.inject(this);
+		viewModel = new ViewModelProvider(this, viewModelFactory)
+				.get(ForumViewModel.class);
 	}
 
 	@Override
-	protected ThreadListController<Forum, ForumPostItem> getController() {
-		return forumController;
+	protected ThreadListViewModel<ForumPostItem> getViewModel() {
+		return viewModel;
+	}
+
+	@Override
+	protected ThreadItemAdapter<ForumPostItem> createAdapter() {
+		return new ThreadItemAdapter<>(this);
 	}
 
 	@Override
@@ -59,36 +61,33 @@ public class ForumActivity extends
 		super.onCreate(state);
 
 		Toolbar toolbar = setUpCustomToolbar(false);
-
-		Intent i = getIntent();
-		String groupName = i.getStringExtra(GROUP_NAME);
-		if (groupName != null) setTitle(groupName);
-		else loadNamedGroup();
-
 		// Open member list on Toolbar click
-		if (toolbar != null) {
-			toolbar.setOnClickListener(v -> {
-				Intent i1 = new Intent(ForumActivity.this,
-						ForumSharingStatusActivity.class);
-				i1.putExtra(GROUP_ID, groupId.getBytes());
-				startActivity(i1);
-			});
+		toolbar.setOnClickListener(v -> {
+			Intent i = new Intent(ForumActivity.this,
+					ForumSharingStatusActivity.class);
+			i.putExtra(GROUP_ID, groupId.getBytes());
+			startActivity(i);
+		});
+
+		String groupName = getIntent().getStringExtra(GROUP_NAME);
+		if (groupName != null) {
+			setTitle(groupName);
+		} else {
+			observeOnce(viewModel.loadForum(), this, forum ->
+					setTitle(forum.getName())
+			);
 		}
 	}
 
 	@Override
-	protected void onNamedGroupLoaded(Forum forum) {
-		setTitle(forum.getName());
+	public void onStart() {
+		super.onStart();
+		viewModel.clearForumPostNotification();
 	}
 
 	@Override
-	protected ThreadItemAdapter<ForumPostItem> createAdapter(
-			LinearLayoutManager layoutManager) {
-		return new ThreadItemAdapter<>(this, layoutManager);
-	}
-
-	@Override
-	protected void onActivityResult(int request, int result, Intent data) {
+	protected void onActivityResult(int request, int result,
+			@Nullable Intent data) {
 		super.onActivityResult(request, result, data);
 
 		if (request == REQUEST_SHARE_FORUM && result == RESULT_OK) {
@@ -101,32 +100,31 @@ public class ForumActivity extends
 		// Inflate the menu items for use in the action bar
 		MenuInflater inflater = getMenuInflater();
 		inflater.inflate(R.menu.forum_actions, menu);
-
-		return super.onCreateOptionsMenu(menu);
+		super.onCreateOptionsMenu(menu);
+		return true;
 	}
 
 	@Override
 	public boolean onOptionsItemSelected(MenuItem item) {
 		// Handle presses on the action bar items
-		switch (item.getItemId()) {
-			case R.id.action_forum_share:
-				Intent i2 = new Intent(this, ShareForumActivity.class);
-				i2.setFlags(FLAG_ACTIVITY_CLEAR_TOP);
-				i2.putExtra(GROUP_ID, groupId.getBytes());
-				startActivityForResult(i2, REQUEST_SHARE_FORUM);
-				return true;
-			case R.id.action_forum_sharing_status:
-				Intent i3 = new Intent(this, ForumSharingStatusActivity.class);
-				i3.setFlags(FLAG_ACTIVITY_CLEAR_TOP);
-				i3.putExtra(GROUP_ID, groupId.getBytes());
-				startActivity(i3);
-				return true;
-			case R.id.action_forum_delete:
-				showUnsubscribeDialog();
-				return true;
-			default:
-				return super.onOptionsItemSelected(item);
+		int itemId = item.getItemId();
+		if (itemId == R.id.action_forum_share) {
+			Intent i2 = new Intent(this, ShareForumActivity.class);
+			i2.setFlags(FLAG_ACTIVITY_CLEAR_TOP);
+			i2.putExtra(GROUP_ID, groupId.getBytes());
+			startActivityForResult(i2, REQUEST_SHARE_FORUM);
+			return true;
+		} else if (itemId == R.id.action_forum_sharing_status) {
+			Intent i3 = new Intent(this, ForumSharingStatusActivity.class);
+			i3.setFlags(FLAG_ACTIVITY_CLEAR_TOP);
+			i3.putExtra(GROUP_ID, groupId.getBytes());
+			startActivity(i3);
+			return true;
+		} else if (itemId == R.id.action_forum_delete) {
+			showUnsubscribeDialog();
+			return true;
 		}
+		return super.onOptionsItemSelected(item);
 	}
 
 	@Override
@@ -135,7 +133,7 @@ public class ForumActivity extends
 	}
 
 	private void showUnsubscribeDialog() {
-		OnClickListener okListener = (dialog, which) -> deleteForum();
+		OnClickListener okListener = (dialog, which) -> viewModel.deleteForum();
 		AlertDialog.Builder builder = new AlertDialog.Builder(this,
 				R.style.BriarDialogTheme);
 		builder.setTitle(getString(R.string.dialog_title_leave_forum));
@@ -145,27 +143,4 @@ public class ForumActivity extends
 		builder.show();
 	}
 
-	private void deleteForum() {
-		forumController.deleteNamedGroup(
-				new UiResultExceptionHandler<Void, DbException>(this) {
-					@Override
-					public void onResultUi(Void v) {
-						Toast.makeText(ForumActivity.this,
-								R.string.forum_left_toast, LENGTH_SHORT).show();
-					}
-
-					@Override
-					public void onExceptionUi(DbException exception) {
-						handleException(exception);
-					}
-				});
-	}
-
-	@Override
-	public void onForumLeft(ContactId c) {
-		sharingController.remove(c);
-		setToolbarSubTitle(sharingController.getTotalCount(),
-				sharingController.getOnlineCount());
-	}
-
 }

briar-android/src/main/java/org/briarproject/briar/android/forum/ForumController.java

@@ -1,18 +0,0 @@
-package org.briarproject.briar.android.forum;
-
-import org.briarproject.bramble.api.contact.ContactId;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
-import org.briarproject.briar.android.threaded.ThreadListController;
-import org.briarproject.briar.api.forum.Forum;
-
-import androidx.annotation.UiThread;
-
-@NotNullByDefault
-interface ForumController extends ThreadListController<Forum, ForumPostItem> {
-
-	interface ForumListener extends ThreadListListener<ForumPostItem> {
-		@UiThread
-		void onForumLeft(ContactId c);
-	}
-
-}

briar-android/src/main/java/org/briarproject/briar/android/forum/ForumControllerImpl.java

@@ -1,185 +0,0 @@
-package org.briarproject.briar.android.forum;
-
-import org.briarproject.bramble.api.contact.Contact;
-import org.briarproject.bramble.api.contact.ContactId;
-import org.briarproject.bramble.api.crypto.CryptoExecutor;
-import org.briarproject.bramble.api.db.DatabaseExecutor;
-import org.briarproject.bramble.api.db.DbException;
-import org.briarproject.bramble.api.event.Event;
-import org.briarproject.bramble.api.event.EventBus;
-import org.briarproject.bramble.api.identity.IdentityManager;
-import org.briarproject.bramble.api.identity.LocalAuthor;
-import org.briarproject.bramble.api.lifecycle.LifecycleManager;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
-import org.briarproject.bramble.api.sync.MessageId;
-import org.briarproject.bramble.api.system.Clock;
-import org.briarproject.briar.android.controller.handler.ResultExceptionHandler;
-import org.briarproject.briar.android.forum.ForumController.ForumListener;
-import org.briarproject.briar.android.threaded.ThreadListControllerImpl;
-import org.briarproject.briar.api.android.AndroidNotificationManager;
-import org.briarproject.briar.api.client.MessageTracker;
-import org.briarproject.briar.api.client.MessageTracker.GroupCount;
-import org.briarproject.briar.api.forum.Forum;
-import org.briarproject.briar.api.forum.ForumInvitationResponse;
-import org.briarproject.briar.api.forum.ForumManager;
-import org.briarproject.briar.api.forum.ForumPost;
-import org.briarproject.briar.api.forum.ForumPostHeader;
-import org.briarproject.briar.api.forum.ForumSharingManager;
-import org.briarproject.briar.api.forum.event.ForumInvitationResponseReceivedEvent;
-import org.briarproject.briar.api.forum.event.ForumPostReceivedEvent;
-import org.briarproject.briar.api.sharing.event.ContactLeftShareableEvent;
-
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.concurrent.Executor;
-import java.util.logging.Logger;
-
-import javax.annotation.Nullable;
-import javax.inject.Inject;
-
-import static java.lang.Math.max;
-import static java.util.logging.Level.WARNING;
-import static org.briarproject.bramble.util.LogUtils.logException;
-
-@NotNullByDefault
-class ForumControllerImpl extends
-		ThreadListControllerImpl<Forum, ForumPostItem, ForumPostHeader, ForumPost, ForumListener>
-		implements ForumController {
-
-	private static final Logger LOG =
-			Logger.getLogger(ForumControllerImpl.class.getName());
-
-	private final ForumManager forumManager;
-	private final ForumSharingManager forumSharingManager;
-
-	@Inject
-	ForumControllerImpl(@DatabaseExecutor Executor dbExecutor,
-			LifecycleManager lifecycleManager, IdentityManager identityManager,
-			@CryptoExecutor Executor cryptoExecutor,
-			ForumManager forumManager, ForumSharingManager forumSharingManager,
-			EventBus eventBus, Clock clock, MessageTracker messageTracker,
-			AndroidNotificationManager notificationManager) {
-		super(dbExecutor, lifecycleManager, identityManager, cryptoExecutor,
-				eventBus, clock, notificationManager, messageTracker);
-		this.forumManager = forumManager;
-		this.forumSharingManager = forumSharingManager;
-	}
-
-	@Override
-	public void onActivityStart() {
-		super.onActivityStart();
-		notificationManager.clearForumPostNotification(getGroupId());
-	}
-
-	@Override
-	public void eventOccurred(Event e) {
-		super.eventOccurred(e);
-
-		if (e instanceof ForumPostReceivedEvent) {
-			ForumPostReceivedEvent f = (ForumPostReceivedEvent) e;
-			if (f.getGroupId().equals(getGroupId())) {
-				LOG.info("Forum post received, adding...");
-				listener.onItemReceived(buildItem(f.getHeader(), f.getText()));
-			}
-		} else if (e instanceof ForumInvitationResponseReceivedEvent) {
-			ForumInvitationResponseReceivedEvent f =
-					(ForumInvitationResponseReceivedEvent) e;
-			ForumInvitationResponse r = f.getMessageHeader();
-			if (r.getShareableId().equals(getGroupId()) && r.wasAccepted()) {
-				LOG.info("Forum invitation was accepted");
-				listener.onInvitationAccepted(f.getContactId());
-			}
-		} else if (e instanceof ContactLeftShareableEvent) {
-			ContactLeftShareableEvent c = (ContactLeftShareableEvent) e;
-			if (c.getGroupId().equals(getGroupId())) {
-				LOG.info("Forum left by contact");
-				listener.onForumLeft(c.getContactId());
-			}
-		}
-	}
-
-	@Override
-	protected Forum loadNamedGroup() throws DbException {
-		return forumManager.getForum(getGroupId());
-	}
-
-	@Override
-	protected Collection<ForumPostHeader> loadHeaders() throws DbException {
-		return forumManager.getPostHeaders(getGroupId());
-	}
-
-	@Override
-	protected String loadMessageText(ForumPostHeader h) throws DbException {
-		return forumManager.getPostText(h.getId());
-	}
-
-	@Override
-	protected void markRead(MessageId id) throws DbException {
-		forumManager.setReadFlag(getGroupId(), id, true);
-	}
-
-	@Override
-	public void loadSharingContacts(
-			ResultExceptionHandler<Collection<ContactId>, DbException> handler) {
-		runOnDbThread(() -> {
-			try {
-				Collection<Contact> contacts =
-						forumSharingManager.getSharedWith(getGroupId());
-				Collection<ContactId> contactIds =
-						new ArrayList<>(contacts.size());
-				for (Contact c : contacts) contactIds.add(c.getId());
-				handler.onResult(contactIds);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				handler.onException(e);
-			}
-		});
-	}
-
-	@Override
-	public void createAndStoreMessage(String text,
-			@Nullable ForumPostItem parentItem,
-			ResultExceptionHandler<ForumPostItem, DbException> handler) {
-		runOnDbThread(() -> {
-			try {
-				LocalAuthor author = identityManager.getLocalAuthor();
-				GroupCount count = forumManager.getGroupCount(getGroupId());
-				long timestamp = max(count.getLatestMsgTime() + 1,
-						clock.currentTimeMillis());
-				MessageId parentId = parentItem != null ?
-						parentItem.getId() : null;
-				createMessage(text, timestamp, parentId, author, handler);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				handler.onException(e);
-			}
-		});
-	}
-
-	private void createMessage(String text, long timestamp,
-			@Nullable MessageId parentId, LocalAuthor author,
-			ResultExceptionHandler<ForumPostItem, DbException> handler) {
-		cryptoExecutor.execute(() -> {
-			LOG.info("Creating forum post...");
-			ForumPost msg = forumManager.createLocalPost(getGroupId(), text,
-					timestamp, parentId, author);
-			storePost(msg, text, handler);
-		});
-	}
-
-	@Override
-	protected ForumPostHeader addLocalMessage(ForumPost p) throws DbException {
-		return forumManager.addLocalPost(p);
-	}
-
-	@Override
-	protected void deleteNamedGroup(Forum forum) throws DbException {
-		forumManager.removeForum(forum);
-	}
-
-	@Override
-	protected ForumPostItem buildItem(ForumPostHeader header, String text) {
-		return new ForumPostItem(header, text);
-	}
-
-}

briar-android/src/main/java/org/briarproject/briar/android/forum/ForumListViewModel.java

@@ -40,10 +40,8 @@ import androidx.annotation.UiThread;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.MutableLiveData;
 
-import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
 import static org.briarproject.bramble.util.LogUtils.logDuration;
-import static org.briarproject.bramble.util.LogUtils.logException;
 import static org.briarproject.bramble.util.LogUtils.now;
 import static org.briarproject.briar.api.forum.ForumManager.CLIENT_ID;
 
@@ -164,15 +162,11 @@ class ForumListViewModel extends DbViewModel implements EventListener {
 	}
 
 	void loadForumInvitations() {
-		runOnDbThread(() -> {
-			try {
-				long start = now();
-				int available = forumSharingManager.getInvitations().size();
-				logDuration(LOG, "Loading available", start);
-				numInvitations.postValue(available);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
+		runOnDbThreadOrLogException(() -> {
+			long start = now();
+			int available = forumSharingManager.getInvitations().size();
+			logDuration(LOG, "Loading available", start);
+			numInvitations.postValue(available);
 		});
 	}
 

briar-android/src/main/java/org/briarproject/briar/android/forum/ForumModule.java

@@ -1,32 +1,23 @@
 package org.briarproject.briar.android.forum;
 
-import org.briarproject.briar.android.activity.ActivityScope;
-import org.briarproject.briar.android.activity.BaseActivity;
 import org.briarproject.briar.android.viewmodel.ViewModelKey;
 
 import androidx.lifecycle.ViewModel;
 import dagger.Binds;
 import dagger.Module;
-import dagger.Provides;
 import dagger.multibindings.IntoMap;
 
 @Module
-public class ForumModule {
+public interface ForumModule {
 
-	@Module
-	public interface BindsModule {
-		@Binds
-		@IntoMap
-		@ViewModelKey(ForumListViewModel.class)
-		ViewModel bindForumListViewModel(ForumListViewModel forumListViewModel);
-	}
+	@Binds
+	@IntoMap
+	@ViewModelKey(ForumListViewModel.class)
+	ViewModel bindForumListViewModel(ForumListViewModel forumListViewModel);
 
-	@ActivityScope
-	@Provides
-	ForumController provideForumController(BaseActivity activity,
-			ForumControllerImpl forumController) {
-		activity.addLifecycleController(forumController);
-		return forumController;
-	}
+	@Binds
+	@IntoMap
+	@ViewModelKey(ForumViewModel.class)
+	ViewModel bindForumViewModel(ForumViewModel forumViewModel);
 
 }

briar-android/src/main/java/org/briarproject/briar/android/forum/ForumPostItem.java

@@ -6,7 +6,6 @@ import org.briarproject.bramble.api.sync.MessageId;
 import org.briarproject.briar.android.threaded.ThreadItem;
 import org.briarproject.briar.api.forum.ForumPostHeader;
 
-import javax.annotation.Nullable;
 import javax.annotation.concurrent.NotThreadSafe;
 
 @NotThreadSafe
@@ -17,9 +16,4 @@ class ForumPostItem extends ThreadItem {
 				h.getAuthorInfo(), h.isRead());
 	}
 
-	ForumPostItem(MessageId messageId, @Nullable MessageId parentId,
-			String text, long timestamp, Author author, AuthorInfo authorInfo) {
-		super(messageId, parentId, text, timestamp, author, authorInfo, true);
-	}
-
 }

briar-android/src/main/java/org/briarproject/briar/android/forum/ForumViewModel.java

@@ -0,0 +1,203 @@
+package org.briarproject.briar.android.forum;
+
+import android.app.Application;
+import android.widget.Toast;
+
+import org.briarproject.bramble.api.contact.Contact;
+import org.briarproject.bramble.api.contact.ContactId;
+import org.briarproject.bramble.api.crypto.CryptoExecutor;
+import org.briarproject.bramble.api.db.DatabaseExecutor;
+import org.briarproject.bramble.api.db.DbException;
+import org.briarproject.bramble.api.db.Transaction;
+import org.briarproject.bramble.api.db.TransactionManager;
+import org.briarproject.bramble.api.event.Event;
+import org.briarproject.bramble.api.event.EventBus;
+import org.briarproject.bramble.api.identity.IdentityManager;
+import org.briarproject.bramble.api.identity.LocalAuthor;
+import org.briarproject.bramble.api.lifecycle.LifecycleManager;
+import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
+import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
+import org.briarproject.bramble.api.sync.MessageId;
+import org.briarproject.bramble.api.system.AndroidExecutor;
+import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.briar.R;
+import org.briarproject.briar.android.sharing.SharingController;
+import org.briarproject.briar.android.threaded.ThreadListViewModel;
+import org.briarproject.briar.api.android.AndroidNotificationManager;
+import org.briarproject.briar.api.client.MessageTracker;
+import org.briarproject.briar.api.client.MessageTracker.GroupCount;
+import org.briarproject.briar.api.client.PostHeader;
+import org.briarproject.briar.api.forum.Forum;
+import org.briarproject.briar.api.forum.ForumInvitationResponse;
+import org.briarproject.briar.api.forum.ForumManager;
+import org.briarproject.briar.api.forum.ForumPost;
+import org.briarproject.briar.api.forum.ForumPostHeader;
+import org.briarproject.briar.api.forum.ForumSharingManager;
+import org.briarproject.briar.api.forum.event.ForumInvitationResponseReceivedEvent;
+import org.briarproject.briar.api.forum.event.ForumPostReceivedEvent;
+import org.briarproject.briar.api.sharing.event.ContactLeftShareableEvent;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.concurrent.Executor;
+import java.util.logging.Logger;
+
+import javax.annotation.Nullable;
+import javax.inject.Inject;
+
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+
+import static android.widget.Toast.LENGTH_SHORT;
+import static java.lang.Math.max;
+import static java.util.logging.Logger.getLogger;
+import static org.briarproject.bramble.util.LogUtils.logDuration;
+import static org.briarproject.bramble.util.LogUtils.now;
+
+@MethodsNotNullByDefault
+@ParametersNotNullByDefault
+class ForumViewModel extends ThreadListViewModel<ForumPostItem> {
+
+	private static final Logger LOG = getLogger(ForumViewModel.class.getName());
+
+	private final ForumManager forumManager;
+	private final ForumSharingManager forumSharingManager;
+
+	@Inject
+	ForumViewModel(Application application,
+			@DatabaseExecutor Executor dbExecutor,
+			LifecycleManager lifecycleManager,
+			TransactionManager db,
+			AndroidExecutor androidExecutor,
+			IdentityManager identityManager,
+			AndroidNotificationManager notificationManager,
+			SharingController sharingController,
+			@CryptoExecutor Executor cryptoExecutor,
+			Clock clock,
+			MessageTracker messageTracker,
+			EventBus eventBus,
+			ForumManager forumManager,
+			ForumSharingManager forumSharingManager) {
+		super(application, dbExecutor, lifecycleManager, db, androidExecutor,
+				identityManager, notificationManager, sharingController,
+				cryptoExecutor, clock, messageTracker, eventBus);
+		this.forumManager = forumManager;
+		this.forumSharingManager = forumSharingManager;
+	}
+
+	@Override
+	public void eventOccurred(Event e) {
+		if (e instanceof ForumPostReceivedEvent) {
+			ForumPostReceivedEvent f = (ForumPostReceivedEvent) e;
+			if (f.getGroupId().equals(groupId)) {
+				LOG.info("Forum post received, adding...");
+				ForumPostItem item = buildItem(f.getHeader(), f.getText());
+				addItem(item);
+			}
+		} else if (e instanceof ForumInvitationResponseReceivedEvent) {
+			ForumInvitationResponseReceivedEvent f =
+					(ForumInvitationResponseReceivedEvent) e;
+			ForumInvitationResponse r = f.getMessageHeader();
+			if (r.getShareableId().equals(groupId) && r.wasAccepted()) {
+				LOG.info("Forum invitation was accepted");
+				sharingController.add(f.getContactId());
+			}
+		} else if (e instanceof ContactLeftShareableEvent) {
+			ContactLeftShareableEvent c = (ContactLeftShareableEvent) e;
+			if (c.getGroupId().equals(groupId)) {
+				LOG.info("Forum left by contact");
+				sharingController.remove(c.getContactId());
+			}
+		} else {
+			super.eventOccurred(e);
+		}
+	}
+
+	void clearForumPostNotification() {
+		notificationManager.clearForumPostNotification(groupId);
+	}
+
+	LiveData<Forum> loadForum() {
+		MutableLiveData<Forum> forum = new MutableLiveData<>();
+		runOnDbThreadOrLogException(() ->
+				forum.postValue(forumManager.getForum(groupId)));
+		return forum;
+	}
+
+	@Override
+	public void loadItems() {
+		loadList(txn -> {
+			long start = now();
+			List<ForumPostHeader> headers =
+					forumManager.getPostHeaders(txn, groupId);
+			logDuration(LOG, "Loading headers", start);
+			return createItems(txn, headers, this::buildItem);
+		}, this::setItems);
+	}
+
+	@Override
+	public void createAndStoreMessage(String text,
+			@Nullable MessageId parentId) {
+		runOnDbThreadOrLogException(() -> {
+			LocalAuthor author = identityManager.getLocalAuthor();
+			GroupCount count = forumManager.getGroupCount(groupId);
+			long timestamp = max(count.getLatestMsgTime() + 1,
+					clock.currentTimeMillis());
+			createMessage(text, timestamp, parentId, author);
+		});
+	}
+
+	private void createMessage(String text, long timestamp,
+			@Nullable MessageId parentId, LocalAuthor author) {
+		cryptoExecutor.execute(() -> {
+			LOG.info("Creating forum post...");
+			ForumPost msg = forumManager.createLocalPost(groupId, text,
+					timestamp, parentId, author);
+			storePost(msg, text);
+		});
+	}
+
+	private void storePost(ForumPost msg, String text) {
+		runOnDbThreadOrLogException(() -> {
+			long start = now();
+			ForumPostHeader header = forumManager.addLocalPost(msg);
+			addItemAsync(buildItem(header, text));
+			logDuration(LOG, "Storing forum post", start);
+		});
+	}
+
+	private ForumPostItem buildItem(ForumPostHeader header, String text) {
+		return new ForumPostItem(header, text);
+	}
+
+	@Override
+	protected String loadMessageText(Transaction txn, PostHeader header)
+			throws DbException {
+		return forumManager.getPostText(txn, header.getId());
+	}
+
+	@Override
+	protected void markItemRead(ForumPostItem item) {
+		runOnDbThreadOrLogException(() ->
+				forumManager.setReadFlag(groupId, item.getId(), true));
+	}
+
+	public void loadSharingContacts() {
+		runOnDbThreadOrLogException(true, txn -> {
+			Collection<Contact> contacts =
+					forumSharingManager.getSharedWith(txn, groupId);
+			Collection<ContactId> contactIds = new ArrayList<>(contacts.size());
+			for (Contact c : contacts) contactIds.add(c.getId());
+			txn.attach(() -> sharingController.addAll(contactIds));
+		});
+	}
+
+	void deleteForum() {
+		runOnDbThreadOrLogException(() ->
+				forumManager.removeForum(forumManager.getForum(groupId)));
+		Toast.makeText(getApplication(), R.string.forum_left_toast,
+				LENGTH_SHORT).show();
+	}
+
+}

briar-android/src/main/java/org/briarproject/briar/android/login/LoginUtils.java

@@ -1,13 +1,17 @@
 package org.briarproject.briar.android.login;
 
 import android.content.Context;
+import android.graphics.drawable.Drawable;
 
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.briar.R;
 
 import androidx.appcompat.app.AlertDialog;
 
-import static org.briarproject.briar.android.util.UiUtils.getDialogIcon;
+import static androidx.core.content.ContextCompat.getColor;
+import static androidx.core.content.ContextCompat.getDrawable;
+import static androidx.core.graphics.drawable.DrawableCompat.setTint;
+import static java.util.Objects.requireNonNull;
 
 @NotNullByDefault
 class LoginUtils {
@@ -15,7 +19,9 @@ class LoginUtils {
 	static AlertDialog createKeyStrengthenerErrorDialog(Context ctx) {
 		AlertDialog.Builder builder =
 				new AlertDialog.Builder(ctx, R.style.BriarDialogTheme);
-		builder.setIcon(getDialogIcon(ctx, R.drawable.alerts_and_states_error));
+		Drawable icon = getDrawable(ctx, R.drawable.alerts_and_states_error);
+		setTint(requireNonNull(icon), getColor(ctx, R.color.color_primary));
+		builder.setIcon(icon);
 		builder.setTitle(R.string.dialog_title_cannot_check_password);
 		builder.setMessage(R.string.dialog_message_cannot_check_password);
 		builder.setPositiveButton(R.string.ok, null);

briar-android/src/main/java/org/briarproject/briar/android/navdrawer/NavDrawerActivity.java

@@ -2,7 +2,6 @@ package org.briarproject.briar.android.navdrawer;
 
 import android.content.Intent;
 import android.content.res.Configuration;
-import android.graphics.drawable.Drawable;
 import android.net.Uri;
 import android.os.Bundle;
 import android.view.LayoutInflater;
@@ -60,7 +59,6 @@ import androidx.fragment.app.FragmentTransaction;
 import androidx.lifecycle.MutableLiveData;
 import androidx.lifecycle.ViewModelProvider;
 import androidx.lifecycle.ViewModelProviders;
-import androidx.vectordrawable.graphics.drawable.VectorDrawableCompat;
 import uk.co.samuelwall.materialtaptargetprompt.MaterialTapTargetPrompt;
 
 import static android.view.View.GONE;
@@ -435,7 +433,8 @@ public class NavDrawerActivity extends BriarActivity implements
 				Transport t = getItem(position);
 
 				ImageView icon = view.findViewById(R.id.imageView);
-				icon.setImageResource(t.iconDrawable);
+				icon.setImageDrawable(ContextCompat.getDrawable(
+						NavDrawerActivity.this, t.iconDrawable));
 				icon.setColorFilter(ContextCompat.getColor(
 						NavDrawerActivity.this, t.iconColor));
 
@@ -477,13 +476,11 @@ public class NavDrawerActivity extends BriarActivity implements
 	private void showTransportsOnboarding(boolean show, ImageView imageView) {
 		if (show) {
 			int color = resolveColorAttribute(this, R.attr.colorControlNormal);
-			Drawable drawable = VectorDrawableCompat
-					.create(getResources(), R.drawable.transport_tor, null);
 			new MaterialTapTargetPrompt.Builder(NavDrawerActivity.this,
 					R.style.OnboardingDialogTheme).setTarget(imageView)
 					.setPrimaryText(R.string.network_settings_title)
 					.setSecondaryText(R.string.transports_onboarding_text)
-					.setIconDrawable(drawable)
+					.setIcon(R.drawable.transport_tor)
 					.setIconDrawableColourFilter(color)
 					.setBackgroundColour(
 							ContextCompat.getColor(this, R.color.briar_primary))

briar-android/src/main/java/org/briarproject/briar/android/navdrawer/NavDrawerViewModel.java

@@ -3,7 +3,6 @@ package org.briarproject.briar.android.navdrawer;
 import android.app.Application;
 
 import org.briarproject.bramble.api.db.DatabaseExecutor;
-import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.TransactionManager;
 import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
@@ -66,34 +65,27 @@ public class NavDrawerViewModel extends DbViewModel {
 
 	@UiThread
 	void checkExpiryWarning() {
-		runOnDbThread(() -> {
-			try {
-				Settings settings =
-						settingsManager.getSettings(SETTINGS_NAMESPACE);
-				int warningInt = settings.getInt(EXPIRY_DATE_WARNING, 0);
+		runOnDbThreadOrLogException(() -> {
+			Settings settings = settingsManager.getSettings(SETTINGS_NAMESPACE);
+			int warningInt = settings.getInt(EXPIRY_DATE_WARNING, 0);
 
-				if (warningInt == 0) {
-					// we have not warned before
+			if (warningInt == 0) {
+				// we have not warned before
+				showExpiryWarning.postValue(true);
+			} else {
+				long warningLong = warningInt * 1000L;
+				long now = System.currentTimeMillis();
+				long daysSinceLastWarning =
+						(now - warningLong) / DAYS.toMillis(1);
+				long daysBeforeExpiry = (EXPIRY_DATE - now) / DAYS.toMillis(1);
+
+				if (daysSinceLastWarning >= 30) {
+					showExpiryWarning.postValue(true);
+				} else if (daysBeforeExpiry <= 3 && daysSinceLastWarning > 0) {
 					showExpiryWarning.postValue(true);
 				} else {
-					long warningLong = warningInt * 1000L;
-					long now = System.currentTimeMillis();
-					long daysSinceLastWarning =
-							(now - warningLong) / DAYS.toMillis(1);
-					long daysBeforeExpiry =
-							(EXPIRY_DATE - now) / DAYS.toMillis(1);
-
-					if (daysSinceLastWarning >= 30) {
-						showExpiryWarning.postValue(true);
-					} else if (daysBeforeExpiry <= 3 &&
-							daysSinceLastWarning > 0) {
-						showExpiryWarning.postValue(true);
-					} else {
-						showExpiryWarning.postValue(false);
-					}
+					showExpiryWarning.postValue(false);
 				}
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
 			}
 		});
 	}
@@ -101,15 +93,11 @@ public class NavDrawerViewModel extends DbViewModel {
 	@UiThread
 	void expiryWarningDismissed() {
 		showExpiryWarning.setValue(false);
-		runOnDbThread(() -> {
-			try {
-				Settings settings = new Settings();
-				int date = (int) (System.currentTimeMillis() / 1000L);
-				settings.putInt(EXPIRY_DATE_WARNING, date);
-				settingsManager.mergeSettings(settings, SETTINGS_NAMESPACE);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
+		runOnDbThreadOrLogException(() -> {
+			Settings settings = new Settings();
+			int date = (int) (System.currentTimeMillis() / 1000L);
+			settings.putInt(EXPIRY_DATE_WARNING, date);
+			settingsManager.mergeSettings(settings, SETTINGS_NAMESPACE);
 		});
 	}
 
@@ -125,15 +113,12 @@ public class NavDrawerViewModel extends DbViewModel {
 			return;
 		}
 		runOnDbThread(() -> {
-			try {
-				Settings settings =
-						settingsManager.getSettings(SETTINGS_NAMESPACE);
-				boolean ask = settings.getBoolean(DOZE_ASK_AGAIN, true);
-				shouldAskForDozeWhitelisting.postValue(ask);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				shouldAskForDozeWhitelisting.postValue(true);
-			}
+			Settings settings = settingsManager.getSettings(SETTINGS_NAMESPACE);
+			boolean ask = settings.getBoolean(DOZE_ASK_AGAIN, true);
+			shouldAskForDozeWhitelisting.postValue(ask);
+		}, e -> {
+			logException(LOG, WARNING, e);
+			shouldAskForDozeWhitelisting.postValue(true);
 		});
 	}
 
@@ -145,30 +130,21 @@ public class NavDrawerViewModel extends DbViewModel {
 	@UiThread
 	void checkTransportsOnboarding() {
 		if (showTransportsOnboarding.getValue() != null) return;
-		runOnDbThread(() -> {
-			try {
-				Settings settings =
-						settingsManager.getSettings(SETTINGS_NAMESPACE);
-				boolean show =
-						settings.getBoolean(SHOW_TRANSPORTS_ONBOARDING, true);
-				showTransportsOnboarding.postValue(show);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
+		runOnDbThreadOrLogException(() -> {
+			Settings settings = settingsManager.getSettings(SETTINGS_NAMESPACE);
+			boolean show =
+					settings.getBoolean(SHOW_TRANSPORTS_ONBOARDING, true);
+			showTransportsOnboarding.postValue(show);
 		});
 	}
 
 	@UiThread
 	void transportsOnboardingShown() {
 		showTransportsOnboarding.setValue(false);
-		runOnDbThread(() -> {
-			try {
-				Settings settings = new Settings();
-				settings.putBoolean(SHOW_TRANSPORTS_ONBOARDING, false);
-				settingsManager.mergeSettings(settings, SETTINGS_NAMESPACE);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
+		runOnDbThreadOrLogException(() -> {
+			Settings settings = new Settings();
+			settings.putBoolean(SHOW_TRANSPORTS_ONBOARDING, false);
+			settingsManager.mergeSettings(settings, SETTINGS_NAMESPACE);
 		});
 	}
 }

briar-android/src/main/java/org/briarproject/briar/android/navdrawer/PluginViewModel.java

@@ -45,12 +45,10 @@ import static android.bluetooth.BluetoothAdapter.ACTION_STATE_CHANGED;
 import static android.bluetooth.BluetoothAdapter.EXTRA_STATE;
 import static android.bluetooth.BluetoothAdapter.STATE_ON;
 import static java.util.logging.Level.INFO;
-import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
 import static org.briarproject.bramble.api.plugin.Plugin.PREF_PLUGIN_ENABLE;
 import static org.briarproject.bramble.api.plugin.Plugin.State.STARTING_STOPPING;
 import static org.briarproject.bramble.util.LogUtils.logDuration;
-import static org.briarproject.bramble.util.LogUtils.logException;
 import static org.briarproject.bramble.util.LogUtils.now;
 
 @NotNullByDefault
@@ -185,20 +183,16 @@ public class PluginViewModel extends DbViewModel implements EventListener {
 	}
 
 	private void loadSettings() {
-		runOnDbThread(() -> {
-			try {
-				boolean tor = isPluginEnabled(TorConstants.ID,
-						TorConstants.DEFAULT_PREF_PLUGIN_ENABLE);
-				torEnabledSetting.postValue(tor);
-				boolean wifi = isPluginEnabled(LanTcpConstants.ID,
-						LanTcpConstants.DEFAULT_PREF_PLUGIN_ENABLE);
-				wifiEnabledSetting.postValue(wifi);
-				boolean bt = isPluginEnabled(BluetoothConstants.ID,
-						BluetoothConstants.DEFAULT_PREF_PLUGIN_ENABLE);
-				btEnabledSetting.postValue(bt);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
+		runOnDbThreadOrLogException(() -> {
+			boolean tor = isPluginEnabled(TorConstants.ID,
+					TorConstants.DEFAULT_PREF_PLUGIN_ENABLE);
+			torEnabledSetting.postValue(tor);
+			boolean wifi = isPluginEnabled(LanTcpConstants.ID,
+					LanTcpConstants.DEFAULT_PREF_PLUGIN_ENABLE);
+			wifiEnabledSetting.postValue(wifi);
+			boolean bt = isPluginEnabled(BluetoothConstants.ID,
+					BluetoothConstants.DEFAULT_PREF_PLUGIN_ENABLE);
+			btEnabledSetting.postValue(bt);
 		});
 	}
 
@@ -222,14 +216,10 @@ public class PluginViewModel extends DbViewModel implements EventListener {
 	}
 
 	private void mergeSettings(Settings s, String namespace) {
-		runOnDbThread(() -> {
-			try {
-				long start = now();
-				settingsManager.mergeSettings(s, namespace);
-				logDuration(LOG, "Merging settings", start);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
+		runOnDbThreadOrLogException(() -> {
+			long start = now();
+			settingsManager.mergeSettings(s, namespace);
+			logDuration(LOG, "Merging settings", start);
 		});
 	}
 

briar-android/src/main/java/org/briarproject/briar/android/navdrawer/TransportsActivity.java

@@ -141,7 +141,8 @@ public class TransportsActivity extends BriarActivity {
 				Transport t = getItem(position);
 
 				ImageView icon = view.findViewById(R.id.icon);
-				icon.setImageResource(t.iconDrawable);
+				icon.setImageDrawable(ContextCompat.getDrawable(
+						TransportsActivity.this, t.iconDrawable));
 				icon.setColorFilter(ContextCompat.getColor(
 						TransportsActivity.this, t.iconColor));
 

briar-android/src/main/java/org/briarproject/briar/android/privategroup/conversation/GroupActivity.java

@@ -1,67 +1,59 @@
 package org.briarproject.briar.android.privategroup.conversation;
 
-import android.content.DialogInterface;
-import android.content.DialogInterface.OnClickListener;
 import android.content.Intent;
 import android.os.Bundle;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
 
-import org.briarproject.bramble.api.contact.ContactId;
-import org.briarproject.bramble.api.db.DbException;
-import org.briarproject.bramble.api.identity.AuthorId;
-import org.briarproject.bramble.api.identity.LocalAuthor;
 import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
 import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
 import org.briarproject.briar.R;
 import org.briarproject.briar.android.activity.ActivityComponent;
-import org.briarproject.briar.android.controller.handler.UiExceptionHandler;
-import org.briarproject.briar.android.controller.handler.UiResultExceptionHandler;
-import org.briarproject.briar.android.privategroup.conversation.GroupController.GroupListener;
 import org.briarproject.briar.android.privategroup.creation.GroupInviteActivity;
 import org.briarproject.briar.android.privategroup.memberlist.GroupMemberListActivity;
 import org.briarproject.briar.android.privategroup.reveal.RevealContactsActivity;
 import org.briarproject.briar.android.threaded.ThreadListActivity;
-import org.briarproject.briar.android.threaded.ThreadListController;
-import org.briarproject.briar.api.privategroup.PrivateGroup;
-import org.briarproject.briar.api.privategroup.Visibility;
+import org.briarproject.briar.android.threaded.ThreadListViewModel;
 
 import javax.annotation.Nullable;
 import javax.inject.Inject;
 
 import androidx.appcompat.app.AlertDialog;
 import androidx.appcompat.widget.Toolbar;
-import androidx.recyclerview.widget.LinearLayoutManager;
+import androidx.lifecycle.ViewModelProvider;
 
 import static android.view.View.GONE;
 import static android.view.View.VISIBLE;
 import static org.briarproject.briar.android.activity.RequestCodes.REQUEST_GROUP_INVITE;
+import static org.briarproject.briar.android.util.UiUtils.observeOnce;
 import static org.briarproject.briar.api.privategroup.PrivateGroupConstants.MAX_GROUP_POST_TEXT_LENGTH;
 
 @MethodsNotNullByDefault
 @ParametersNotNullByDefault
 public class GroupActivity extends
-		ThreadListActivity<PrivateGroup, GroupMessageItem, GroupMessageAdapter>
-		implements GroupListener, OnClickListener {
+		ThreadListActivity<GroupMessageItem, GroupMessageAdapter> {
 
 	@Inject
-	GroupController controller;
+	ViewModelProvider.Factory viewModelFactory;
 
-	@Nullable
-	private Boolean isCreator = null;
-	private boolean isDissolved = false;
-	private MenuItem revealMenuItem, inviteMenuItem, leaveMenuItem,
-			dissolveMenuItem;
+	private GroupViewModel viewModel;
 
 	@Override
 	public void injectActivity(ActivityComponent component) {
 		component.inject(this);
+		viewModel = new ViewModelProvider(this, viewModelFactory)
+				.get(GroupViewModel.class);
 	}
 
 	@Override
-	protected ThreadListController<PrivateGroup, GroupMessageItem> getController() {
-		return controller;
+	protected ThreadListViewModel<GroupMessageItem> getViewModel() {
+		return viewModel;
+	}
+
+	@Override
+	protected GroupMessageAdapter createAdapter() {
+		return new GroupMessageAdapter(this);
 	}
 
 	@Override
@@ -69,65 +61,33 @@ public class GroupActivity extends
 		super.onCreate(state);
 
 		Toolbar toolbar = setUpCustomToolbar(false);
-
-		Intent i = getIntent();
-		String groupName = i.getStringExtra(GROUP_NAME);
-		if (groupName != null) setTitle(groupName);
-		loadNamedGroup();
-
 		// Open member list on Toolbar click
-		if (toolbar != null) {
-			toolbar.setOnClickListener(v -> {
-				Intent i1 = new Intent(GroupActivity.this,
-						GroupMemberListActivity.class);
-				i1.putExtra(GROUP_ID, groupId.getBytes());
-				startActivity(i1);
-			});
-		}
+		toolbar.setOnClickListener(v -> {
+			Intent i = new Intent(GroupActivity.this,
+					GroupMemberListActivity.class);
+			i.putExtra(GROUP_ID, groupId.getBytes());
+			startActivity(i);
+		});
 
+		String groupName = getIntent().getStringExtra(GROUP_NAME);
+		if (groupName != null) setTitle(groupName);
+		observeOnce(viewModel.getPrivateGroup(), this, privateGroup ->
+				setTitle(privateGroup.getName())
+		);
+		observeOnce(viewModel.isCreator(), this, adapter::setIsCreator);
+
+		// start with group disabled and enable when not dissolved
 		setGroupEnabled(false);
+		viewModel.isDissolved().observe(this, dissolved -> {
+			setGroupEnabled(!dissolved);
+			if (dissolved) onGroupDissolved();
+		});
 	}
 
 	@Override
-	protected GroupMessageAdapter createAdapter(
-			LinearLayoutManager layoutManager) {
-		return new GroupMessageAdapter(this, layoutManager);
-	}
-
-	@Override
-	protected void loadItems() {
-		controller.isDissolved(
-				new UiResultExceptionHandler<Boolean, DbException>(this) {
-					@Override
-					public void onResultUi(Boolean isDissolved) {
-						setGroupEnabled(!isDissolved);
-						GroupActivity.super.loadItems();
-					}
-
-					@Override
-					public void onExceptionUi(DbException exception) {
-						handleException(exception);
-					}
-				});
-	}
-
-	@Override
-	protected void onNamedGroupLoaded(PrivateGroup group) {
-		setTitle(group.getName());
-		controller.loadLocalAuthor(
-				new UiResultExceptionHandler<LocalAuthor, DbException>(this) {
-					@Override
-					public void onResultUi(LocalAuthor author) {
-						isCreator = group.getCreator().equals(author);
-						adapter.setPerspective(isCreator);
-						showMenuItems();
-					}
-
-					@Override
-					public void onExceptionUi(DbException exception) {
-						handleException(exception);
-					}
-				});
+	public void onStart() {
+		super.onStart();
+		viewModel.clearGroupMessageNotifications();
 	}
 
 	@Override
@@ -136,74 +96,61 @@ public class GroupActivity extends
 		MenuInflater inflater = getMenuInflater();
 		inflater.inflate(R.menu.group_actions, menu);
 
-		revealMenuItem = menu.findItem(R.id.action_group_reveal);
-		inviteMenuItem = menu.findItem(R.id.action_group_invite);
-		leaveMenuItem = menu.findItem(R.id.action_group_leave);
-		dissolveMenuItem = menu.findItem(R.id.action_group_dissolve);
-
-		// all role-dependent items are invisible until we know our role
-		revealMenuItem.setVisible(false);
-		inviteMenuItem.setVisible(false);
-		leaveMenuItem.setVisible(false);
-		dissolveMenuItem.setVisible(false);
-
-		// show items based on role
-		showMenuItems();
-
-		return super.onCreateOptionsMenu(menu);
+		// show items based on role (which will not change, so observe once)
+		observeOnce(viewModel.isCreator(), this, isCreator -> {
+			menu.findItem(R.id.action_group_reveal).setVisible(!isCreator);
+			menu.findItem(R.id.action_group_invite).setVisible(isCreator);
+			menu.findItem(R.id.action_group_leave).setVisible(!isCreator);
+			menu.findItem(R.id.action_group_dissolve).setVisible(isCreator);
+		});
+		super.onCreateOptionsMenu(menu);
+		return true;
 	}
 
 	@Override
 	public boolean onOptionsItemSelected(MenuItem item) {
-		switch (item.getItemId()) {
-			case R.id.action_group_member_list:
-				Intent i1 = new Intent(this, GroupMemberListActivity.class);
-				i1.putExtra(GROUP_ID, groupId.getBytes());
-				startActivity(i1);
-				return true;
-			case R.id.action_group_reveal:
-				if (isCreator == null || isCreator)
-					throw new IllegalStateException();
-				Intent i2 = new Intent(this, RevealContactsActivity.class);
-				i2.putExtra(GROUP_ID, groupId.getBytes());
-				startActivity(i2);
-				return true;
-			case R.id.action_group_invite:
-				if (isCreator == null || !isCreator)
-					throw new IllegalStateException();
-				Intent i3 = new Intent(this, GroupInviteActivity.class);
-				i3.putExtra(GROUP_ID, groupId.getBytes());
-				startActivityForResult(i3, REQUEST_GROUP_INVITE);
-				return true;
-			case R.id.action_group_leave:
-				if (isCreator == null || isCreator)
-					throw new IllegalStateException();
-				showLeaveGroupDialog();
-				return true;
-			case R.id.action_group_dissolve:
-				if (isCreator == null || !isCreator)
-					throw new IllegalStateException();
-				showDissolveGroupDialog();
-			default:
-				return super.onOptionsItemSelected(item);
+		int itemId = item.getItemId();
+		if (itemId == R.id.action_group_member_list) {
+			Intent i = new Intent(this, GroupMemberListActivity.class);
+			i.putExtra(GROUP_ID, groupId.getBytes());
+			startActivity(i);
+			return true;
+		} else if (itemId == R.id.action_group_reveal) {
+			if (viewModel.isCreator().getValue())
+				throw new IllegalStateException();
+			Intent i = new Intent(this, RevealContactsActivity.class);
+			i.putExtra(GROUP_ID, groupId.getBytes());
+			startActivity(i);
+			return true;
+		} else if (itemId == R.id.action_group_invite) {
+			if (!viewModel.isCreator().getValue())
+				throw new IllegalStateException();
+			Intent i = new Intent(this, GroupInviteActivity.class);
+			i.putExtra(GROUP_ID, groupId.getBytes());
+			startActivityForResult(i, REQUEST_GROUP_INVITE);
+			return true;
+		} else if (itemId == R.id.action_group_leave) {
+			if (viewModel.isCreator().getValue())
+				throw new IllegalStateException();
+			showLeaveGroupDialog();
+			return true;
+		} else if (itemId == R.id.action_group_dissolve) {
+			if (!viewModel.isCreator().getValue())
+				throw new IllegalStateException();
+			showDissolveGroupDialog();
+			return true;
 		}
+		return super.onOptionsItemSelected(item);
 	}
 
 	@Override
-	protected void onActivityResult(int request, int result, Intent data) {
+	protected void onActivityResult(int request, int result,
+			@Nullable Intent data) {
 		if (request == REQUEST_GROUP_INVITE && result == RESULT_OK) {
 			displaySnackbar(R.string.groups_invitation_sent);
 		} else super.onActivityResult(request, result, data);
 	}
 
-	@Override
-	public void onItemReceived(GroupMessageItem item) {
-		super.onItemReceived(item);
-		if (item instanceof JoinMessageItem) {
-			if (((JoinMessageItem) item).isInitial()) loadSharingContacts();
-		}
-	}
-
 	@Override
 	protected int getMaxTextLength() {
 		return MAX_GROUP_POST_TEXT_LENGTH;
@@ -211,11 +158,10 @@ public class GroupActivity extends
 
 	@Override
 	public void onReplyClick(GroupMessageItem item) {
-		if (!isDissolved) super.onReplyClick(item);
+		if (!viewModel.isDissolved().getValue()) super.onReplyClick(item);
 	}
 
 	private void setGroupEnabled(boolean enabled) {
-		isDissolved = !enabled;
 		sendController.setReady(enabled);
 		list.getRecyclerView().setAlpha(enabled ? 1f : 0.5f);
 
@@ -227,21 +173,13 @@ public class GroupActivity extends
 		}
 	}
 
-	private void showMenuItems() {
-		// we need to have the menu items and know if we are the creator
-		if (leaveMenuItem == null || isCreator == null) return;
-		revealMenuItem.setVisible(!isCreator);
-		inviteMenuItem.setVisible(isCreator);
-		leaveMenuItem.setVisible(!isCreator);
-		dissolveMenuItem.setVisible(isCreator);
-	}
-
 	private void showLeaveGroupDialog() {
 		AlertDialog.Builder builder =
 				new AlertDialog.Builder(this, R.style.BriarDialogTheme);
 		builder.setTitle(getString(R.string.groups_leave_dialog_title));
 		builder.setMessage(getString(R.string.groups_leave_dialog_message));
-		builder.setNegativeButton(R.string.dialog_button_leave, this);
+		builder.setNegativeButton(R.string.dialog_button_leave,
+				(d, w) -> deleteGroup());
 		builder.setPositiveButton(R.string.cancel, null);
 		builder.show();
 	}
@@ -251,37 +189,19 @@ public class GroupActivity extends
 				new AlertDialog.Builder(this, R.style.BriarDialogTheme);
 		builder.setTitle(getString(R.string.groups_dissolve_dialog_title));
 		builder.setMessage(getString(R.string.groups_dissolve_dialog_message));
-		builder.setNegativeButton(R.string.groups_dissolve_button, this);
+		builder.setNegativeButton(R.string.groups_dissolve_button,
+				(d, w) -> deleteGroup());
 		builder.setPositiveButton(R.string.cancel, null);
 		builder.show();
 	}
 
-	@Override
-	public void onClick(DialogInterface dialog, int which) {
-		controller.deleteNamedGroup(
-				new UiExceptionHandler<DbException>(this) {
-					// The activity is going to be destroyed by the
-					// GroupRemovedEvent being fired
-					@Override
-					public void onExceptionUi(DbException exception) {
-						handleException(exception);
-					}
-				});
+	private void deleteGroup() {
+		// The activity is going to be destroyed by the
+		// GroupRemovedEvent being fired
+		viewModel.deletePrivateGroup();
 	}
 
-	@Override
-	public void onContactRelationshipRevealed(AuthorId memberId, ContactId c,
-			Visibility v) {
-		adapter.updateVisibility(memberId, v);
-
-		sharingController.add(c);
-		setToolbarSubTitle(sharingController.getTotalCount(),
-				sharingController.getOnlineCount());
-	}
-
-	@Override
 	public void onGroupDissolved() {
-		setGroupEnabled(false);
 		AlertDialog.Builder builder =
 				new AlertDialog.Builder(this, R.style.BriarDialogTheme);
 		builder.setTitle(getString(R.string.groups_dissolved_dialog_title));

briar-android/src/main/java/org/briarproject/briar/android/privategroup/conversation/GroupController.java

@@ -1,33 +0,0 @@
-package org.briarproject.briar.android.privategroup.conversation;
-
-import org.briarproject.bramble.api.contact.ContactId;
-import org.briarproject.bramble.api.db.DbException;
-import org.briarproject.bramble.api.identity.AuthorId;
-import org.briarproject.bramble.api.identity.LocalAuthor;
-import org.briarproject.briar.android.controller.handler.ResultExceptionHandler;
-import org.briarproject.briar.android.threaded.ThreadListController;
-import org.briarproject.briar.api.privategroup.PrivateGroup;
-import org.briarproject.briar.api.privategroup.Visibility;
-
-import androidx.annotation.UiThread;
-
-public interface GroupController
-		extends ThreadListController<PrivateGroup, GroupMessageItem> {
-
-	void loadLocalAuthor(
-			ResultExceptionHandler<LocalAuthor, DbException> handler);
-
-	void isDissolved(
-			ResultExceptionHandler<Boolean, DbException> handler);
-
-	interface GroupListener extends ThreadListListener<GroupMessageItem> {
-
-		@UiThread
-		void onContactRelationshipRevealed(AuthorId memberId,
-				ContactId contactId, Visibility v);
-
-		@UiThread
-		void onGroupDissolved();
-	}
-
-}

briar-android/src/main/java/org/briarproject/briar/android/privategroup/conversation/GroupControllerImpl.java

@@ -1,242 +0,0 @@
-package org.briarproject.briar.android.privategroup.conversation;
-
-import org.briarproject.bramble.api.contact.ContactId;
-import org.briarproject.bramble.api.crypto.CryptoExecutor;
-import org.briarproject.bramble.api.db.DatabaseExecutor;
-import org.briarproject.bramble.api.db.DbException;
-import org.briarproject.bramble.api.event.Event;
-import org.briarproject.bramble.api.event.EventBus;
-import org.briarproject.bramble.api.identity.IdentityManager;
-import org.briarproject.bramble.api.identity.LocalAuthor;
-import org.briarproject.bramble.api.lifecycle.LifecycleManager;
-import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
-import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
-import org.briarproject.bramble.api.sync.MessageId;
-import org.briarproject.bramble.api.system.Clock;
-import org.briarproject.briar.android.controller.handler.ResultExceptionHandler;
-import org.briarproject.briar.android.privategroup.conversation.GroupController.GroupListener;
-import org.briarproject.briar.android.threaded.ThreadListControllerImpl;
-import org.briarproject.briar.api.android.AndroidNotificationManager;
-import org.briarproject.briar.api.client.MessageTracker;
-import org.briarproject.briar.api.client.MessageTracker.GroupCount;
-import org.briarproject.briar.api.privategroup.GroupMember;
-import org.briarproject.briar.api.privategroup.GroupMessage;
-import org.briarproject.briar.api.privategroup.GroupMessageFactory;
-import org.briarproject.briar.api.privategroup.GroupMessageHeader;
-import org.briarproject.briar.api.privategroup.JoinMessageHeader;
-import org.briarproject.briar.api.privategroup.PrivateGroup;
-import org.briarproject.briar.api.privategroup.PrivateGroupManager;
-import org.briarproject.briar.api.privategroup.event.ContactRelationshipRevealedEvent;
-import org.briarproject.briar.api.privategroup.event.GroupDissolvedEvent;
-import org.briarproject.briar.api.privategroup.event.GroupInvitationResponseReceivedEvent;
-import org.briarproject.briar.api.privategroup.event.GroupMessageAddedEvent;
-import org.briarproject.briar.api.privategroup.invitation.GroupInvitationResponse;
-
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.concurrent.Executor;
-import java.util.logging.Logger;
-
-import javax.annotation.Nullable;
-import javax.inject.Inject;
-
-import static java.lang.Math.max;
-import static java.util.logging.Level.WARNING;
-import static org.briarproject.bramble.util.LogUtils.logException;
-
-@MethodsNotNullByDefault
-@ParametersNotNullByDefault
-class GroupControllerImpl extends
-		ThreadListControllerImpl<PrivateGroup, GroupMessageItem, GroupMessageHeader, GroupMessage, GroupListener>
-		implements GroupController {
-
-	private static final Logger LOG =
-			Logger.getLogger(GroupControllerImpl.class.getName());
-
-	private final PrivateGroupManager privateGroupManager;
-	private final GroupMessageFactory groupMessageFactory;
-
-	@Inject
-	GroupControllerImpl(@DatabaseExecutor Executor dbExecutor,
-			LifecycleManager lifecycleManager, IdentityManager identityManager,
-			@CryptoExecutor Executor cryptoExecutor,
-			PrivateGroupManager privateGroupManager,
-			GroupMessageFactory groupMessageFactory, EventBus eventBus,
-			MessageTracker messageTracker, Clock clock,
-			AndroidNotificationManager notificationManager) {
-		super(dbExecutor, lifecycleManager, identityManager, cryptoExecutor,
-				eventBus, clock, notificationManager, messageTracker);
-		this.privateGroupManager = privateGroupManager;
-		this.groupMessageFactory = groupMessageFactory;
-	}
-
-	@Override
-	public void onActivityStart() {
-		super.onActivityStart();
-		notificationManager.clearGroupMessageNotification(getGroupId());
-	}
-
-	@Override
-	public void eventOccurred(Event e) {
-		super.eventOccurred(e);
-
-		if (e instanceof GroupMessageAddedEvent) {
-			GroupMessageAddedEvent g = (GroupMessageAddedEvent) e;
-			if (!g.isLocal() && g.getGroupId().equals(getGroupId())) {
-				LOG.info("Group message received, adding...");
-				listener.onItemReceived(buildItem(g.getHeader(), g.getText()));
-			}
-		} else if (e instanceof ContactRelationshipRevealedEvent) {
-			ContactRelationshipRevealedEvent c =
-					(ContactRelationshipRevealedEvent) e;
-			if (getGroupId().equals(c.getGroupId())) {
-				listener.onContactRelationshipRevealed(c.getMemberId(),
-						c.getContactId(), c.getVisibility());
-			}
-		} else if (e instanceof GroupInvitationResponseReceivedEvent) {
-			GroupInvitationResponseReceivedEvent g =
-					(GroupInvitationResponseReceivedEvent) e;
-			GroupInvitationResponse r = g.getMessageHeader();
-			if (getGroupId().equals(r.getShareableId()) && r.wasAccepted()) {
-				listener.onInvitationAccepted(g.getContactId());
-			}
-		} else if (e instanceof GroupDissolvedEvent) {
-			GroupDissolvedEvent g = (GroupDissolvedEvent) e;
-			if (getGroupId().equals(g.getGroupId())) {
-				listener.onGroupDissolved();
-			}
-		}
-	}
-
-	@Override
-	protected PrivateGroup loadNamedGroup() throws DbException {
-		return privateGroupManager.getPrivateGroup(getGroupId());
-	}
-
-	@Override
-	protected Collection<GroupMessageHeader> loadHeaders() throws DbException {
-		return privateGroupManager.getHeaders(getGroupId());
-	}
-
-	@Override
-	protected String loadMessageText(GroupMessageHeader header)
-			throws DbException {
-		if (header instanceof JoinMessageHeader) {
-			// will be looked up later
-			return "";
-		}
-		return privateGroupManager.getMessageText(header.getId());
-	}
-
-	@Override
-	protected void markRead(MessageId id) throws DbException {
-		privateGroupManager.setReadFlag(getGroupId(), id, true);
-	}
-
-	@Override
-	public void loadSharingContacts(
-			ResultExceptionHandler<Collection<ContactId>, DbException> handler) {
-		runOnDbThread(() -> {
-			try {
-				Collection<GroupMember> members =
-						privateGroupManager.getMembers(getGroupId());
-				Collection<ContactId> contactIds = new ArrayList<>();
-				for (GroupMember m : members) {
-					if (m.getContactId() != null)
-						contactIds.add(m.getContactId());
-				}
-				handler.onResult(contactIds);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				handler.onException(e);
-			}
-		});
-	}
-
-	@Override
-	public void createAndStoreMessage(String text,
-			@Nullable GroupMessageItem parentItem,
-			ResultExceptionHandler<GroupMessageItem, DbException> handler) {
-		runOnDbThread(() -> {
-			try {
-				LocalAuthor author = identityManager.getLocalAuthor();
-				MessageId parentId = null;
-				MessageId previousMsgId =
-						privateGroupManager.getPreviousMsgId(getGroupId());
-				GroupCount count =
-						privateGroupManager.getGroupCount(getGroupId());
-				long timestamp = count.getLatestMsgTime();
-				if (parentItem != null) parentId = parentItem.getId();
-				timestamp = max(clock.currentTimeMillis(), timestamp + 1);
-				createMessage(text, timestamp, parentId, author, previousMsgId,
-						handler);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				handler.onException(e);
-			}
-		});
-	}
-
-	private void createMessage(String text, long timestamp,
-			@Nullable MessageId parentId, LocalAuthor author,
-			MessageId previousMsgId,
-			ResultExceptionHandler<GroupMessageItem, DbException> handler) {
-		cryptoExecutor.execute(() -> {
-			LOG.info("Creating group message...");
-			GroupMessage msg = groupMessageFactory
-					.createGroupMessage(getGroupId(), timestamp,
-							parentId, author, text, previousMsgId);
-			storePost(msg, text, handler);
-		});
-	}
-
-	@Override
-	protected GroupMessageHeader addLocalMessage(GroupMessage message)
-			throws DbException {
-		return privateGroupManager.addLocalMessage(message);
-	}
-
-	@Override
-	protected void deleteNamedGroup(PrivateGroup group) throws DbException {
-		privateGroupManager.removePrivateGroup(group.getId());
-	}
-
-	@Override
-	protected GroupMessageItem buildItem(GroupMessageHeader header,
-			String text) {
-		if (header instanceof JoinMessageHeader) {
-			return new JoinMessageItem((JoinMessageHeader) header, text);
-		}
-		return new GroupMessageItem(header, text);
-	}
-
-	@Override
-	public void loadLocalAuthor(
-			ResultExceptionHandler<LocalAuthor, DbException> handler) {
-		runOnDbThread(() -> {
-			try {
-				LocalAuthor author = identityManager.getLocalAuthor();
-				handler.onResult(author);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				handler.onException(e);
-			}
-		});
-	}
-
-	@Override
-	public void isDissolved(
-			ResultExceptionHandler<Boolean, DbException> handler) {
-		runOnDbThread(() -> {
-			try {
-				boolean isDissolved =
-						privateGroupManager.isDissolved(getGroupId());
-				handler.onResult(isDissolved);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				handler.onException(e);
-			}
-		});
-	}
-
-}

briar-android/src/main/java/org/briarproject/briar/android/privategroup/conversation/GroupConversationModule.java

@@ -1,19 +1,18 @@
 package org.briarproject.briar.android.privategroup.conversation;
 
-import org.briarproject.briar.android.activity.ActivityScope;
-import org.briarproject.briar.android.activity.BaseActivity;
+import org.briarproject.briar.android.viewmodel.ViewModelKey;
 
+import androidx.lifecycle.ViewModel;
+import dagger.Binds;
 import dagger.Module;
-import dagger.Provides;
+import dagger.multibindings.IntoMap;
 
 @Module
-public class GroupConversationModule {
+public interface GroupConversationModule {
+
+	@Binds
+	@IntoMap
+	@ViewModelKey(GroupViewModel.class)
+	ViewModel bindGroupViewModel(GroupViewModel groupViewModel);
 
-	@ActivityScope
-	@Provides
-	GroupController provideGroupController(BaseActivity activity,
-			GroupControllerImpl groupController) {
-		activity.addLifecycleController(groupController);
-		return groupController;
-	}
 }

briar-android/src/main/java/org/briarproject/briar/android/privategroup/conversation/GroupMessageAdapter.java

@@ -4,19 +4,14 @@ import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 
-import org.briarproject.bramble.api.identity.AuthorId;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.briar.R;
 import org.briarproject.briar.android.threaded.BaseThreadItemViewHolder;
 import org.briarproject.briar.android.threaded.ThreadItemAdapter;
 import org.briarproject.briar.android.threaded.ThreadPostViewHolder;
-import org.briarproject.briar.api.privategroup.Visibility;
 
 import androidx.annotation.LayoutRes;
 import androidx.annotation.UiThread;
-import androidx.recyclerview.widget.LinearLayoutManager;
-
-import static androidx.recyclerview.widget.RecyclerView.NO_POSITION;
 
 @UiThread
 @NotNullByDefault
@@ -24,15 +19,14 @@ class GroupMessageAdapter extends ThreadItemAdapter<GroupMessageItem> {
 
 	private boolean isCreator = false;
 
-	GroupMessageAdapter(ThreadItemListener<GroupMessageItem> listener,
-			LinearLayoutManager layoutManager) {
-		super(listener, layoutManager);
+	GroupMessageAdapter(ThreadItemListener<GroupMessageItem> listener) {
+		super(listener);
 	}
 
 	@LayoutRes
 	@Override
 	public int getItemViewType(int position) {
-		GroupMessageItem item = items.get(position);
+		GroupMessageItem item = getItem(position);
 		return item.getLayout();
 	}
 
@@ -47,30 +41,9 @@ class GroupMessageAdapter extends ThreadItemAdapter<GroupMessageItem> {
 		return new ThreadPostViewHolder<>(v);
 	}
 
-	void setPerspective(boolean isCreator) {
+	void setIsCreator(boolean isCreator) {
 		this.isCreator = isCreator;
 		notifyDataSetChanged();
 	}
 
-	void updateVisibility(AuthorId memberId, Visibility v) {
-		int position = findItemPosition(memberId);
-		if (position != NO_POSITION) {
-			GroupMessageItem item = items.get(position);
-			if (item instanceof JoinMessageItem) {
-				((JoinMessageItem) item).setVisibility(v);
-				notifyItemChanged(findItemPosition(item), item);
-			}
-		}
-	}
-
-	private int findItemPosition(AuthorId a) {
-		int count = items.size();
-		for (int i = 0; i < count; i++) {
-			GroupMessageItem item = items.get(i);
-			if (item.getAuthor().getId().equals(a))
-				return i;
-		}
-		return NO_POSITION; // Not found
-	}
-
 }

briar-android/src/main/java/org/briarproject/briar/android/privategroup/conversation/GroupViewModel.java

@@ -0,0 +1,254 @@
+package org.briarproject.briar.android.privategroup.conversation;
+
+import android.app.Application;
+
+import org.briarproject.bramble.api.contact.ContactId;
+import org.briarproject.bramble.api.crypto.CryptoExecutor;
+import org.briarproject.bramble.api.db.DatabaseExecutor;
+import org.briarproject.bramble.api.db.DbException;
+import org.briarproject.bramble.api.db.Transaction;
+import org.briarproject.bramble.api.db.TransactionManager;
+import org.briarproject.bramble.api.event.Event;
+import org.briarproject.bramble.api.event.EventBus;
+import org.briarproject.bramble.api.identity.Author;
+import org.briarproject.bramble.api.identity.IdentityManager;
+import org.briarproject.bramble.api.identity.LocalAuthor;
+import org.briarproject.bramble.api.lifecycle.LifecycleManager;
+import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
+import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
+import org.briarproject.bramble.api.sync.GroupId;
+import org.briarproject.bramble.api.sync.MessageId;
+import org.briarproject.bramble.api.system.AndroidExecutor;
+import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.briar.android.sharing.SharingController;
+import org.briarproject.briar.android.threaded.ThreadListViewModel;
+import org.briarproject.briar.api.android.AndroidNotificationManager;
+import org.briarproject.briar.api.client.MessageTracker;
+import org.briarproject.briar.api.client.MessageTracker.GroupCount;
+import org.briarproject.briar.api.client.PostHeader;
+import org.briarproject.briar.api.privategroup.GroupMember;
+import org.briarproject.briar.api.privategroup.GroupMessage;
+import org.briarproject.briar.api.privategroup.GroupMessageFactory;
+import org.briarproject.briar.api.privategroup.GroupMessageHeader;
+import org.briarproject.briar.api.privategroup.JoinMessageHeader;
+import org.briarproject.briar.api.privategroup.PrivateGroup;
+import org.briarproject.briar.api.privategroup.PrivateGroupManager;
+import org.briarproject.briar.api.privategroup.event.ContactRelationshipRevealedEvent;
+import org.briarproject.briar.api.privategroup.event.GroupDissolvedEvent;
+import org.briarproject.briar.api.privategroup.event.GroupInvitationResponseReceivedEvent;
+import org.briarproject.briar.api.privategroup.event.GroupMessageAddedEvent;
+import org.briarproject.briar.api.privategroup.invitation.GroupInvitationResponse;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.concurrent.Executor;
+import java.util.logging.Logger;
+
+import javax.annotation.Nullable;
+import javax.inject.Inject;
+
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+
+import static java.lang.Math.max;
+import static java.util.logging.Logger.getLogger;
+import static org.briarproject.bramble.util.LogUtils.logDuration;
+import static org.briarproject.bramble.util.LogUtils.now;
+
+@MethodsNotNullByDefault
+@ParametersNotNullByDefault
+class GroupViewModel extends ThreadListViewModel<GroupMessageItem> {
+
+	private static final Logger LOG = getLogger(GroupViewModel.class.getName());
+
+	private final PrivateGroupManager privateGroupManager;
+	private final GroupMessageFactory groupMessageFactory;
+
+	private final MutableLiveData<PrivateGroup> privateGroup =
+			new MutableLiveData<>();
+	private final MutableLiveData<Boolean> isCreator = new MutableLiveData<>();
+	private final MutableLiveData<Boolean> isDissolved =
+			new MutableLiveData<>();
+
+	@Inject
+	GroupViewModel(Application application,
+			@DatabaseExecutor Executor dbExecutor,
+			LifecycleManager lifecycleManager,
+			TransactionManager db,
+			AndroidExecutor androidExecutor,
+			EventBus eventBus,
+			IdentityManager identityManager,
+			AndroidNotificationManager notificationManager,
+			SharingController sharingController,
+			@CryptoExecutor Executor cryptoExecutor,
+			Clock clock,
+			MessageTracker messageTracker,
+			PrivateGroupManager privateGroupManager,
+			GroupMessageFactory groupMessageFactory) {
+		super(application, dbExecutor, lifecycleManager, db, androidExecutor,
+				identityManager, notificationManager, sharingController,
+				cryptoExecutor, clock, messageTracker, eventBus);
+		this.privateGroupManager = privateGroupManager;
+		this.groupMessageFactory = groupMessageFactory;
+	}
+
+	@Override
+	public void eventOccurred(Event e) {
+		if (e instanceof GroupMessageAddedEvent) {
+			GroupMessageAddedEvent g = (GroupMessageAddedEvent) e;
+			// only act on non-local messages in this group
+			if (!g.isLocal() && g.getGroupId().equals(groupId)) {
+				LOG.info("Group message received, adding...");
+				GroupMessageItem item = buildItem(g.getHeader(), g.getText());
+				addItem(item);
+				if (item instanceof JoinMessageItem &&
+						(((JoinMessageItem) item).isInitial())) {
+					loadSharingContacts();
+				}
+			}
+		} else if (e instanceof GroupInvitationResponseReceivedEvent) {
+			GroupInvitationResponseReceivedEvent g =
+					(GroupInvitationResponseReceivedEvent) e;
+			GroupInvitationResponse r = g.getMessageHeader();
+			if (r.getShareableId().equals(groupId) && r.wasAccepted()) {
+				sharingController.add(g.getContactId());
+			}
+		} else if (e instanceof ContactRelationshipRevealedEvent) {
+			ContactRelationshipRevealedEvent c =
+					(ContactRelationshipRevealedEvent) e;
+			if (c.getGroupId().equals(groupId)) {
+				sharingController.add(c.getContactId());
+			}
+		} else if (e instanceof GroupDissolvedEvent) {
+			GroupDissolvedEvent g = (GroupDissolvedEvent) e;
+			if (g.getGroupId().equals(groupId)) {
+				isDissolved.setValue(true);
+			}
+		} else {
+			super.eventOccurred(e);
+		}
+	}
+
+	@Override
+	public void setGroupId(GroupId groupId) {
+		super.setGroupId(groupId);
+		loadPrivateGroup(groupId);
+	}
+
+	public void clearGroupMessageNotifications() {
+		notificationManager.clearGroupMessageNotification(groupId);
+	}
+
+	private void loadPrivateGroup(GroupId groupId) {
+		runOnDbThreadOrLogException(() -> {
+			PrivateGroup g = privateGroupManager.getPrivateGroup(groupId);
+			privateGroup.postValue(g);
+			Author author = identityManager.getLocalAuthor();
+			isCreator.postValue(g.getCreator().equals(author));
+		});
+	}
+
+	@Override
+	public void loadItems() {
+		loadList(txn -> {
+			// check first if group is dissolved
+			isDissolved
+					.postValue(privateGroupManager.isDissolved(txn, groupId));
+			// now continue to load the items
+			long start = now();
+			List<GroupMessageHeader> headers =
+					privateGroupManager.getHeaders(txn, groupId);
+			logDuration(LOG, "Loading headers", start);
+			return createItems(txn, headers, this::buildItem);
+		}, this::setItems);
+	}
+
+	private GroupMessageItem buildItem(GroupMessageHeader header, String text) {
+		if (header instanceof JoinMessageHeader) {
+			return new JoinMessageItem((JoinMessageHeader) header, text);
+		}
+		return new GroupMessageItem(header, text);
+	}
+
+	@Override
+	protected String loadMessageText(
+			Transaction txn, PostHeader header) throws DbException {
+		if (header instanceof JoinMessageHeader) {
+			// will be looked up later
+			return "";
+		}
+		return privateGroupManager.getMessageText(txn, header.getId());
+	}
+
+	@Override
+	public void createAndStoreMessage(String text,
+			@Nullable MessageId parentId) {
+		runOnDbThreadOrLogException(() -> {
+			LocalAuthor author = identityManager.getLocalAuthor();
+			MessageId previousMsgId =
+					privateGroupManager.getPreviousMsgId(groupId);
+			GroupCount count = privateGroupManager.getGroupCount(groupId);
+			long timestamp = count.getLatestMsgTime();
+			timestamp = max(clock.currentTimeMillis(), timestamp + 1);
+			createMessage(text, timestamp, parentId, author, previousMsgId);
+		});
+	}
+
+	private void createMessage(String text, long timestamp,
+			@Nullable MessageId parentId, LocalAuthor author,
+			MessageId previousMsgId) {
+		cryptoExecutor.execute(() -> {
+			LOG.info("Creating group message...");
+			GroupMessage msg = groupMessageFactory.createGroupMessage(groupId,
+					timestamp, parentId, author, text, previousMsgId);
+			storePost(msg, text);
+		});
+	}
+
+	private void storePost(GroupMessage msg, String text) {
+		runOnDbThreadOrLogException(() -> {
+			long start = now();
+			GroupMessageHeader header =
+					privateGroupManager.addLocalMessage(msg);
+			addItemAsync(buildItem(header, text));
+			logDuration(LOG, "Storing group message", start);
+		});
+	}
+
+	@Override
+	protected void markItemRead(GroupMessageItem item) {
+		runOnDbThreadOrLogException(() ->
+				privateGroupManager.setReadFlag(groupId, item.getId(), true));
+	}
+
+	public void loadSharingContacts() {
+		runOnDbThreadOrLogException(true, txn -> {
+			Collection<GroupMember> members =
+					privateGroupManager.getMembers(txn, groupId);
+			Collection<ContactId> contactIds = new ArrayList<>();
+			for (GroupMember m : members) {
+				if (m.getContactId() != null) contactIds.add(m.getContactId());
+			}
+			txn.attach(() -> sharingController.addAll(contactIds));
+		});
+	}
+
+	void deletePrivateGroup() {
+		runOnDbThreadOrLogException(() ->
+				privateGroupManager.removePrivateGroup(groupId));
+	}
+
+	LiveData<PrivateGroup> getPrivateGroup() {
+		return privateGroup;
+	}
+
+	LiveData<Boolean> isCreator() {
+		return isCreator;
+	}
+
+	LiveData<Boolean> isDissolved() {
+		return isDissolved;
+	}
+
+}

briar-android/src/main/java/org/briarproject/briar/android/privategroup/conversation/JoinMessageItem.java

@@ -2,7 +2,6 @@ package org.briarproject.briar.android.privategroup.conversation;
 
 import org.briarproject.briar.R;
 import org.briarproject.briar.api.privategroup.JoinMessageHeader;
-import org.briarproject.briar.api.privategroup.Visibility;
 
 import javax.annotation.concurrent.NotThreadSafe;
 
@@ -13,12 +12,10 @@ import androidx.annotation.UiThread;
 @NotThreadSafe
 class JoinMessageItem extends GroupMessageItem {
 
-	private Visibility visibility;
 	private final boolean isInitial;
 
 	JoinMessageItem(JoinMessageHeader h, String text) {
 		super(h, text);
-		this.visibility = h.getVisibility();
 		this.isInitial = h.isInitial();
 	}
 
@@ -33,14 +30,6 @@ class JoinMessageItem extends GroupMessageItem {
 		return R.layout.list_item_group_join_notice;
 	}
 
-	Visibility getVisibility() {
-		return visibility;
-	}
-
-	void setVisibility(Visibility visibility) {
-		this.visibility = visibility;
-	}
-
 	boolean isInitial() {
 		return isInitial;
 	}

briar-android/src/main/java/org/briarproject/briar/android/privategroup/list/GroupListViewModel.java

@@ -2,7 +2,6 @@ package org.briarproject.briar.android.privategroup.list;
 
 import android.app.Application;
 
-import org.briarproject.bramble.api.contact.ContactManager;
 import org.briarproject.bramble.api.db.DatabaseExecutor;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.Transaction;
@@ -49,10 +48,8 @@ import androidx.lifecycle.LiveData;
 import androidx.lifecycle.MutableLiveData;
 
 import static java.util.Objects.requireNonNull;
-import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
 import static org.briarproject.bramble.util.LogUtils.logDuration;
-import static org.briarproject.bramble.util.LogUtils.logException;
 import static org.briarproject.bramble.util.LogUtils.now;
 import static org.briarproject.briar.api.privategroup.PrivateGroupManager.CLIENT_ID;
 
@@ -200,25 +197,17 @@ class GroupListViewModel extends DbViewModel implements EventListener {
 	}
 
 	void removeGroup(GroupId g) {
-		runOnDbThread(() -> {
-			try {
-				long start = now();
-				groupManager.removePrivateGroup(g);
-				logDuration(LOG, "Removing group", start);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
+		runOnDbThreadOrLogException(() -> {
+			long start = now();
+			groupManager.removePrivateGroup(g);
+			logDuration(LOG, "Removing group", start);
 		});
 	}
 
 	void loadNumInvitations() {
-		runOnDbThread(() -> {
-			try {
-				int i = groupInvitationManager.getInvitations().size();
-				numInvitations.postValue(i);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
+		runOnDbThreadOrLogException(() -> {
+			int i = groupInvitationManager.getInvitations().size();
+			numInvitations.postValue(i);
 		});
 	}
 

briar-android/src/main/java/org/briarproject/briar/android/sharing/SharingController.java

@@ -0,0 +1,54 @@
+package org.briarproject.briar.android.sharing;
+
+import org.briarproject.bramble.api.contact.ContactId;
+import org.briarproject.bramble.api.event.EventBus;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import java.util.Collection;
+
+import androidx.annotation.UiThread;
+import androidx.lifecycle.LiveData;
+
+@NotNullByDefault
+public interface SharingController {
+
+	/**
+	 * Call this when the owning ViewModel gets cleared,
+	 * so the {@link EventBus} can get unregistered.
+	 */
+	void onCleared();
+
+	/**
+	 * Adds one contact to be tracked.
+	 */
+	@UiThread
+	void add(ContactId c);
+
+	/**
+	 * Adds a collection of contacts to be tracked.
+	 */
+	@UiThread
+	void addAll(Collection<ContactId> contacts);
+
+	/**
+	 * Call this when the contact identified by c is no longer sharing
+	 * the given group identified by GroupId g.
+	 */
+	@UiThread
+	void remove(ContactId c);
+
+	/**
+	 * Returns the total number of contacts that have been added.
+	 */
+	LiveData<SharingInfo> getSharingInfo();
+
+	class SharingInfo {
+		public final int total, online;
+
+		SharingInfo(int total, int online) {
+			this.total = total;
+			this.online = online;
+		}
+	}
+
+}

briar-android/src/main/java/org/briarproject/briar/android/sharing/SharingControllerImpl.java

@@ -0,0 +1,102 @@
+package org.briarproject.briar.android.sharing;
+
+import org.briarproject.bramble.api.connection.ConnectionRegistry;
+import org.briarproject.bramble.api.contact.ContactId;
+import org.briarproject.bramble.api.event.Event;
+import org.briarproject.bramble.api.event.EventBus;
+import org.briarproject.bramble.api.event.EventListener;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.plugin.event.ContactConnectedEvent;
+import org.briarproject.bramble.api.plugin.event.ContactDisconnectedEvent;
+
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.Set;
+
+import javax.inject.Inject;
+
+import androidx.annotation.UiThread;
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+
+@NotNullByDefault
+public class SharingControllerImpl implements SharingController, EventListener {
+
+	private final EventBus eventBus;
+	private final ConnectionRegistry connectionRegistry;
+
+	// UI thread
+	private final Set<ContactId> contacts = new HashSet<>();
+	private final MutableLiveData<SharingInfo> sharingInfo =
+			new MutableLiveData<>();
+
+	@Inject
+	SharingControllerImpl(EventBus eventBus,
+			ConnectionRegistry connectionRegistry) {
+		this.eventBus = eventBus;
+		this.connectionRegistry = connectionRegistry;
+		eventBus.addListener(this);
+	}
+
+	@Override
+	public void onCleared() {
+		eventBus.removeListener(this);
+	}
+
+	@Override
+	public void eventOccurred(Event e) {
+		if (e instanceof ContactConnectedEvent) {
+			setConnected(((ContactConnectedEvent) e).getContactId());
+		} else if (e instanceof ContactDisconnectedEvent) {
+			setConnected(((ContactDisconnectedEvent) e).getContactId());
+		}
+	}
+
+	@UiThread
+	private void setConnected(ContactId c) {
+		if (contacts.contains(c)) {
+			updateLiveData();
+		}
+	}
+
+	@UiThread
+	private void updateLiveData() {
+		int online = getOnlineCount();
+		sharingInfo.setValue(new SharingInfo(contacts.size(), online));
+	}
+
+	private int getOnlineCount() {
+		int online = 0;
+		for (ContactId c : contacts) {
+			if (connectionRegistry.isConnected(c)) online++;
+		}
+		return online;
+	}
+
+	@UiThread
+	@Override
+	public void addAll(Collection<ContactId> c) {
+		contacts.addAll(c);
+		updateLiveData();
+	}
+
+	@UiThread
+	@Override
+	public void add(ContactId c) {
+		contacts.add(c);
+		updateLiveData();
+	}
+
+	@UiThread
+	@Override
+	public void remove(ContactId c) {
+		contacts.remove(c);
+		updateLiveData();
+	}
+
+	@Override
+	public LiveData<SharingInfo> getSharingInfo() {
+		return sharingInfo;
+	}
+
+}

briar-android/src/main/java/org/briarproject/briar/android/sharing/SharingModule.java

@@ -9,36 +9,47 @@ import dagger.Provides;
 @Module
 public class SharingModule {
 
-	@ActivityScope
-	@Provides
-	ShareForumController provideShareForumController(
-			ShareForumControllerImpl shareForumController) {
-		return shareForumController;
+	@Module
+	@Deprecated
+	public static class SharingLegacyModule {
+
+		@ActivityScope
+		@Provides
+		ShareForumController provideShareForumController(
+				ShareForumControllerImpl shareForumController) {
+			return shareForumController;
+		}
+
+		@ActivityScope
+		@Provides
+		BlogInvitationController provideInvitationBlogController(
+				BaseActivity activity,
+				BlogInvitationControllerImpl blogInvitationController) {
+			activity.addLifecycleController(blogInvitationController);
+			return blogInvitationController;
+		}
+
+		@ActivityScope
+		@Provides
+		ForumInvitationController provideInvitationForumController(
+				BaseActivity activity,
+				ForumInvitationControllerImpl forumInvitationController) {
+			activity.addLifecycleController(forumInvitationController);
+			return forumInvitationController;
+		}
+
+		@ActivityScope
+		@Provides
+		ShareBlogController provideShareBlogController(
+				ShareBlogControllerImpl shareBlogController) {
+			return shareBlogController;
+		}
 	}
 
-	@ActivityScope
 	@Provides
-	BlogInvitationController provideInvitationBlogController(
-			BaseActivity activity,
-			BlogInvitationControllerImpl blogInvitationController) {
-		activity.addLifecycleController(blogInvitationController);
-		return blogInvitationController;
-	}
-
-	@ActivityScope
-	@Provides
-	ForumInvitationController provideInvitationForumController(
-			BaseActivity activity,
-			ForumInvitationControllerImpl forumInvitationController) {
-		activity.addLifecycleController(forumInvitationController);
-		return forumInvitationController;
-	}
-
-	@ActivityScope
-	@Provides
-	ShareBlogController provideShareBlogController(
-			ShareBlogControllerImpl shareBlogController) {
-		return shareBlogController;
+	SharingController provideSharingController(
+			SharingControllerImpl sharingController) {
+		return sharingController;
 	}
 
 }

briar-android/src/main/java/org/briarproject/briar/android/threaded/NestedTreeList.java

@@ -1,54 +0,0 @@
-package org.briarproject.briar.android.threaded;
-
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
-import org.briarproject.bramble.api.sync.MessageId;
-import org.briarproject.briar.api.client.MessageTree;
-import org.briarproject.briar.api.client.MessageTree.MessageNode;
-import org.briarproject.briar.client.MessageTreeImpl;
-
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Iterator;
-import java.util.List;
-
-import androidx.annotation.UiThread;
-
-@UiThread
-@NotNullByDefault
-public class NestedTreeList<T extends MessageNode> implements Iterable<T> {
-
-	private final MessageTree<T> tree = new MessageTreeImpl<>();
-	private List<T> depthFirstCollection = new ArrayList<>();
-
-	public void addAll(Collection<T> collection) {
-		tree.add(collection);
-		depthFirstCollection = new ArrayList<>(tree.depthFirstOrder());
-	}
-
-	public void add(T elem) {
-		tree.add(elem);
-		depthFirstCollection = new ArrayList<>(tree.depthFirstOrder());
-	}
-
-	public void clear() {
-		tree.clear();
-		depthFirstCollection.clear();
-	}
-
-	public T get(int index) {
-		return depthFirstCollection.get(index);
-	}
-
-	public int size() {
-		return depthFirstCollection.size();
-	}
-
-	public boolean contains(MessageId m) {
-		return tree.contains(m);
-	}
-
-	@Override
-	public Iterator<T> iterator() {
-		return depthFirstCollection.iterator();
-	}
-}

briar-android/src/main/java/org/briarproject/briar/android/threaded/ThreadItem.java

@@ -99,4 +99,14 @@ public abstract class ThreadItem implements MessageNode {
 		return highlighted;
 	}
 
+	@Override
+	public int hashCode() {
+		return messageId.hashCode();
+	}
+
+	@Override
+	public boolean equals(@Nullable Object o) {
+		return o instanceof ThreadItem &&
+				messageId.equals(((ThreadItem) o).messageId);
+	}
 }

briar-android/src/main/java/org/briarproject/briar/android/threaded/ThreadItemAdapter.java

@@ -4,39 +4,47 @@ import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 
+import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
+import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
 import org.briarproject.bramble.api.sync.MessageId;
 import org.briarproject.briar.R;
 import org.briarproject.briar.android.util.ItemReturningAdapter;
-import org.briarproject.briar.android.util.VersionedAdapter;
-
-import java.util.Collection;
 
 import javax.annotation.Nullable;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.UiThread;
+import androidx.recyclerview.widget.DiffUtil;
 import androidx.recyclerview.widget.LinearLayoutManager;
-import androidx.recyclerview.widget.RecyclerView;
+import androidx.recyclerview.widget.ListAdapter;
 
 import static androidx.recyclerview.widget.RecyclerView.NO_POSITION;
 
 @UiThread
+@MethodsNotNullByDefault
+@ParametersNotNullByDefault
 public class ThreadItemAdapter<I extends ThreadItem>
-		extends RecyclerView.Adapter<BaseThreadItemViewHolder<I>>
-		implements VersionedAdapter, ItemReturningAdapter<I> {
+		extends ListAdapter<I, BaseThreadItemViewHolder<I>>
+		implements ItemReturningAdapter<I> {
 
 	static final int UNDEFINED = -1;
 
-	protected final NestedTreeList<I> items = new NestedTreeList<>();
 	private final ThreadItemListener<I> listener;
-	private final LinearLayoutManager layoutManager;
 
-	private volatile int revision = 0;
+	public ThreadItemAdapter(ThreadItemListener<I> listener) {
+		super(new DiffUtil.ItemCallback<I>() {
+			@Override
+			public boolean areItemsTheSame(I a, I b) {
+				return a.equals(b);
+			}
 
-	public ThreadItemAdapter(ThreadItemListener<I> listener,
-			LinearLayoutManager layoutManager) {
+			@Override
+			public boolean areContentsTheSame(I a, I b) {
+				return a.isHighlighted() == b.isHighlighted() &&
+						a.isRead() && b.isRead();
+			}
+		});
 		this.listener = listener;
-		this.layoutManager = layoutManager;
 	}
 
 	@NonNull
@@ -51,76 +59,27 @@ public class ThreadItemAdapter<I extends ThreadItem>
 	@Override
 	public void onBindViewHolder(@NonNull BaseThreadItemViewHolder<I> ui,
 			int position) {
-		I item = items.get(position);
+		I item = getItem(position);
 		ui.bind(item, listener);
 	}
 
-	@Override
-	public int getItemCount() {
-		return items.size();
-	}
-
-	@Override
-	public int getRevision() {
-		return revision;
-	}
-
-	@Override
-	public void incrementRevision() {
-		revision++;
-	}
-
-	void setItemWithIdVisible(MessageId messageId) {
-		int pos = 0;
-		for (I item : items) {
-			if (item.getId().equals(messageId)) {
-				layoutManager.scrollToPosition(pos);
-				break;
-			}
-			pos++;
-		}
-	}
-
-	public void setItems(Collection<I> items) {
-		this.items.clear();
-		this.items.addAll(items);
-		notifyDataSetChanged();
-	}
-
-	public void add(I item) {
-		items.add(item);
-		notifyItemInserted(findItemPosition(item));
-	}
-
-	@Nullable
-	public I getItemAt(int position) {
-		if (position == NO_POSITION || position >= items.size()) {
-			return null;
-		}
-		return items.get(position);
-	}
-
-	protected int findItemPosition(@Nullable I item) {
-		for (int i = 0; i < items.size(); i++) {
-			if (items.get(i).equals(item)) return i;
+	public int findItemPosition(MessageId id) {
+		for (int i = 0; i < getItemCount(); i++) {
+			if (id.equals(getItem(i).getId())) return i;
 		}
 		return NO_POSITION; // Not found
 	}
 
-	boolean contains(MessageId m) {
-		return items.contains(m);
-	}
-
 	/**
 	 * Highlights the item with the given {@link MessageId}
 	 * and disables the highlight for a previously highlighted item, if any.
-	 *
+	 * <p>
 	 * Only one item can be highlighted at a time.
 	 */
 	void setHighlightedItem(@Nullable MessageId id) {
-		for (int i = 0; i < items.size(); i++) {
-			I item = items.get(i);
-			if (id != null && item.getId().equals(id)) {
+		for (int i = 0; i < getItemCount(); i++) {
+			I item = getItem(i);
+			if (item.getId().equals(id)) {
 				item.setHighlighted(true);
 				notifyItemChanged(i, item);
 			} else if (item.isHighlighted()) {
@@ -132,20 +91,28 @@ public class ThreadItemAdapter<I extends ThreadItem>
 
 	@Nullable
 	I getHighlightedItem() {
-		for (I i : items) {
-			if (i.isHighlighted()) return i;
+		for (int i = 0; i < getItemCount(); i++) {
+			I item = getItem(i);
+			if (item.isHighlighted()) return item;
 		}
 		return null;
 	}
 
+	@Nullable
+	MessageId getFirstVisibleMessageId(LinearLayoutManager layoutManager) {
+		int position = layoutManager.findFirstVisibleItemPosition();
+		if (position == NO_POSITION) return null;
+		return getItemAt(position).getId();
+	}
+
 	/**
 	 * Returns the position of the first unread item below the current viewport
 	 */
-	int getVisibleUnreadPosBottom() {
+	int getVisibleUnreadPosBottom(LinearLayoutManager layoutManager) {
 		int positionBottom = layoutManager.findLastVisibleItemPosition();
 		if (positionBottom == NO_POSITION) return NO_POSITION;
-		for (int i = positionBottom + 1; i < items.size(); i++) {
-			if (!items.get(i).isRead()) return i;
+		for (int i = positionBottom + 1; i < getItemCount(); i++) {
+			if (!getItem(i).isRead()) return i;
 		}
 		return NO_POSITION;
 	}
@@ -153,11 +120,11 @@ public class ThreadItemAdapter<I extends ThreadItem>
 	/**
 	 * Returns the position of the first unread item above the current viewport
 	 */
-	int getVisibleUnreadPosTop() {
+	int getVisibleUnreadPosTop(LinearLayoutManager layoutManager) {
 		int positionTop = layoutManager.findFirstVisibleItemPosition();
 		int position = NO_POSITION;
-		for (int i = 0; i < items.size(); i++) {
-			if (i < positionTop && !items.get(i).isRead()) {
+		for (int i = 0; i < getItemCount(); i++) {
+			if (i < positionTop && !getItem(i).isRead()) {
 				position = i;
 			} else if (i >= positionTop) {
 				return position;
@@ -166,6 +133,11 @@ public class ThreadItemAdapter<I extends ThreadItem>
 		return NO_POSITION;
 	}
 
+	@Override
+	public I getItemAt(int position) {
+		return getItem(position);
+	}
+
 	public interface ThreadItemListener<I> {
 		void onReplyClick(I item);
 	}

briar-android/src/main/java/org/briarproject/briar/android/threaded/ThreadItemList.java

@@ -1,15 +0,0 @@
-package org.briarproject.briar.android.threaded;
-
-import org.briarproject.bramble.api.sync.MessageId;
-
-import java.util.List;
-
-import javax.annotation.Nullable;
-
-public interface ThreadItemList<I extends ThreadItem> extends List<I> {
-
-	@Nullable
-	MessageId getFirstVisibleItemId();
-
-	void setFirstVisibleId(@Nullable MessageId bottomVisibleItemId);
-}

briar-android/src/main/java/org/briarproject/briar/android/threaded/ThreadItemListImpl.java

@@ -1,23 +0,0 @@
-package org.briarproject.briar.android.threaded;
-
-import org.briarproject.bramble.api.sync.MessageId;
-
-import java.util.ArrayList;
-
-import javax.annotation.Nullable;
-
-public class ThreadItemListImpl<I extends ThreadItem> extends ArrayList<I>
-		implements ThreadItemList<I> {
-
-	private MessageId bottomVisibleItemId;
-
-	@Override
-	public MessageId getFirstVisibleItemId() {
-		return bottomVisibleItemId;
-	}
-
-	@Override
-	public void setFirstVisibleId(@Nullable MessageId bottomVisibleItemId) {
-		this.bottomVisibleItemId = bottomVisibleItemId;
-	}
-}

briar-android/src/main/java/org/briarproject/briar/android/threaded/ThreadListActivity.java

@@ -2,25 +2,18 @@ package org.briarproject.briar.android.threaded;
 
 import android.content.Intent;
 import android.os.Bundle;
-import android.os.Parcelable;
 import android.view.MenuItem;
 
 import com.google.android.material.snackbar.Snackbar;
 
-import org.briarproject.bramble.api.contact.ContactId;
-import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
 import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
 import org.briarproject.bramble.api.sync.GroupId;
 import org.briarproject.bramble.api.sync.MessageId;
 import org.briarproject.briar.R;
 import org.briarproject.briar.android.activity.BriarActivity;
-import org.briarproject.briar.android.controller.SharingController;
-import org.briarproject.briar.android.controller.SharingController.SharingListener;
-import org.briarproject.briar.android.controller.handler.UiResultExceptionHandler;
+import org.briarproject.briar.android.sharing.SharingController.SharingInfo;
 import org.briarproject.briar.android.threaded.ThreadItemAdapter.ThreadItemListener;
-import org.briarproject.briar.android.threaded.ThreadListController.ThreadListDataSource;
-import org.briarproject.briar.android.threaded.ThreadListController.ThreadListListener;
 import org.briarproject.briar.android.util.BriarSnackbarBuilder;
 import org.briarproject.briar.android.view.BriarRecyclerView;
 import org.briarproject.briar.android.view.TextInputView;
@@ -28,18 +21,13 @@ import org.briarproject.briar.android.view.TextSendController;
 import org.briarproject.briar.android.view.TextSendController.SendListener;
 import org.briarproject.briar.android.view.UnreadMessageButton;
 import org.briarproject.briar.api.attachment.AttachmentHeader;
-import org.briarproject.briar.api.client.NamedGroup;
 
-import java.util.Collection;
 import java.util.List;
-import java.util.logging.Logger;
 
 import javax.annotation.Nullable;
-import javax.inject.Inject;
 
 import androidx.annotation.CallSuper;
 import androidx.annotation.StringRes;
-import androidx.annotation.UiThread;
 import androidx.appcompat.app.ActionBar;
 import androidx.recyclerview.widget.LinearLayoutManager;
 
@@ -48,32 +36,19 @@ import static org.briarproject.bramble.util.StringUtils.isNullOrEmpty;
 
 @MethodsNotNullByDefault
 @ParametersNotNullByDefault
-public abstract class ThreadListActivity<G extends NamedGroup, I extends ThreadItem, A extends ThreadItemAdapter<I>>
-		extends BriarActivity
-		implements ThreadListListener<I>, SendListener, SharingListener,
-		ThreadItemListener<I>, ThreadListDataSource {
+public abstract class ThreadListActivity<I extends ThreadItem, A extends ThreadItemAdapter<I>>
+		extends BriarActivity implements SendListener, ThreadItemListener<I> {
 
-	protected static final String KEY_REPLY_ID = "replyId";
-
-	private static final Logger LOG =
-			Logger.getLogger(ThreadListActivity.class.getName());
-
-	protected A adapter;
-	private ThreadScrollListener<I> scrollListener;
+	protected final A adapter = createAdapter();
+	protected abstract ThreadListViewModel<I> getViewModel();
+	protected abstract A createAdapter();
 	protected BriarRecyclerView list;
-	private LinearLayoutManager layoutManager;
 	protected TextInputView textInput;
 	protected TextSendController sendController;
 	protected GroupId groupId;
-	@Nullable
-	private Parcelable layoutManagerState;
-	@Nullable
-	private MessageId replyId;
 
-	protected abstract ThreadListController<G, I> getController();
-
-	@Inject
-	protected SharingController sharingController;
+	private LinearLayoutManager layoutManager;
+	private ThreadScrollListener<I> scrollListener;
 
 	@CallSuper
 	@Override
@@ -86,7 +61,8 @@ public abstract class ThreadListActivity<G extends NamedGroup, I extends ThreadI
 		byte[] b = i.getByteArrayExtra(GROUP_ID);
 		if (b == null) throw new IllegalStateException("No GroupId in intent.");
 		groupId = new GroupId(b);
-		getController().setGroupId(groupId);
+		ThreadListViewModel<I> viewModel = getViewModel();
+		viewModel.setGroupId(groupId);
 
 		textInput = findViewById(R.id.text_input_container);
 		sendController = new TextSendController(textInput, this, false);
@@ -100,131 +76,41 @@ public abstract class ThreadListActivity<G extends NamedGroup, I extends ThreadI
 		list = findViewById(R.id.list);
 		layoutManager = new LinearLayoutManager(this);
 		list.setLayoutManager(layoutManager);
-		adapter = createAdapter(layoutManager);
 		list.setAdapter(adapter);
-		scrollListener = new ThreadScrollListener<>(adapter, getController(),
+		scrollListener = new ThreadScrollListener<>(adapter, viewModel,
 				upButton, downButton);
 		list.getRecyclerView().addOnScrollListener(scrollListener);
 
 		upButton.setOnClickListener(v -> {
-			int position = adapter.getVisibleUnreadPosTop();
+			int position = adapter.getVisibleUnreadPosTop(layoutManager);
 			if (position != NO_POSITION) {
 				list.getRecyclerView().scrollToPosition(position);
 			}
 		});
 		downButton.setOnClickListener(v -> {
-			int position = adapter.getVisibleUnreadPosBottom();
+			int position = adapter.getVisibleUnreadPosBottom(layoutManager);
 			if (position != NO_POSITION) {
 				list.getRecyclerView().scrollToPosition(position);
 			}
 		});
 
-		if (state != null) {
-			byte[] replyIdBytes = state.getByteArray(KEY_REPLY_ID);
-			if (replyIdBytes != null) replyId = new MessageId(replyIdBytes);
-		}
+		viewModel.getItems().observe(this, result -> result
+				.onError(this::handleException)
+				.onSuccess(this::displayItems)
+		);
 
-		sharingController.setSharingListener(this);
-		loadSharingContacts();
-	}
+		viewModel.getSharingInfo().observe(this, this::setToolbarSubTitle);
 
-	@Override
-	@Nullable
-	public MessageId getFirstVisibleMessageId() {
-		if (layoutManager != null && adapter != null) {
-			int position =
-					layoutManager.findFirstVisibleItemPosition();
-			I i = adapter.getItemAt(position);
-			return i == null ? null : i.getId();
-		}
-		return null;
-	}
-
-	protected abstract A createAdapter(LinearLayoutManager layoutManager);
-
-	protected void loadNamedGroup() {
-		getController().loadNamedGroup(
-				new UiResultExceptionHandler<G, DbException>(this) {
-					@Override
-					public void onResultUi(G groupItem) {
-						onNamedGroupLoaded(groupItem);
-					}
-
-					@Override
-					public void onExceptionUi(DbException exception) {
-						handleException(exception);
-					}
-				});
-	}
-
-	@UiThread
-	protected abstract void onNamedGroupLoaded(G groupItem);
-
-	protected void loadItems() {
-		int revision = adapter.getRevision();
-		getController().loadItems(
-				new UiResultExceptionHandler<ThreadItemList<I>, DbException>(
-						this) {
-					@Override
-					public void onResultUi(ThreadItemList<I> items) {
-						if (revision == adapter.getRevision()) {
-							adapter.incrementRevision();
-							if (items.isEmpty()) {
-								list.showData();
-							} else {
-								displayItems(items);
-								updateTextInput();
-							}
-						} else {
-							LOG.info("Concurrent update, reloading");
-							loadItems();
-						}
-					}
-
-					@Override
-					public void onExceptionUi(DbException exception) {
-						handleException(exception);
-					}
-				});
-	}
-
-	private void displayItems(ThreadItemList<I> items) {
-		adapter.setItems(items);
-		MessageId messageId = items.getFirstVisibleItemId();
-		if (messageId != null)
-			adapter.setItemWithIdVisible(messageId);
-		list.showData();
-		if (layoutManagerState == null) {
-			list.scrollToPosition(0);  // Scroll to the top
-		} else {
-			layoutManager.onRestoreInstanceState(layoutManagerState);
-		}
-	}
-
-	protected void loadSharingContacts() {
-		getController().loadSharingContacts(
-				new UiResultExceptionHandler<Collection<ContactId>, DbException>(
-						this) {
-					@Override
-					public void onResultUi(Collection<ContactId> contacts) {
-						sharingController.addAll(contacts);
-						int online = sharingController.getOnlineCount();
-						setToolbarSubTitle(contacts.size(), online);
-					}
-
-					@Override
-					public void onExceptionUi(DbException exception) {
-						handleException(exception);
-					}
-				});
+		viewModel.getGroupRemoved().observe(this, removed -> {
+			if (removed) supportFinishAfterTransition();
+		});
 	}
 
 	@CallSuper
 	@Override
 	public void onStart() {
 		super.onStart();
-		sharingController.onStart();
-		loadItems();
+		getViewModel().blockNotifications();
 		list.startPeriodicUpdate();
 	}
 
@@ -232,91 +118,98 @@ public abstract class ThreadListActivity<G extends NamedGroup, I extends ThreadI
 	@Override
 	public void onStop() {
 		super.onStop();
-		sharingController.onStop();
+		getViewModel().unblockNotifications();
 		list.stopPeriodicUpdate();
 	}
 
-	@Override
-	protected void onSaveInstanceState(Bundle outState) {
-		super.onSaveInstanceState(outState);
-		if (layoutManager != null) {
-			layoutManagerState = layoutManager.onSaveInstanceState();
-			outState.putParcelable("layoutManager", layoutManagerState);
-		}
-		if (replyId != null) {
-			outState.putByteArray(KEY_REPLY_ID, replyId.getBytes());
-		}
-	}
-
-	@Override
-	protected void onRestoreInstanceState(Bundle savedInstanceState) {
-		super.onRestoreInstanceState(savedInstanceState);
-		layoutManagerState = savedInstanceState.getParcelable("layoutManager");
-	}
-
 	@Override
 	public boolean onOptionsItemSelected(MenuItem item) {
-		switch (item.getItemId()) {
-			case android.R.id.home:
-				supportFinishAfterTransition();
-				return true;
-			default:
-				return super.onOptionsItemSelected(item);
+		if (item.getItemId() == android.R.id.home) {
+			supportFinishAfterTransition();
+			return true;
 		}
+		return super.onOptionsItemSelected(item);
 	}
 
 	@Override
 	public void onBackPressed() {
 		if (adapter.getHighlightedItem() != null) {
 			textInput.clearText();
-			replyId = null;
+			getViewModel().setReplyId(null);
 			updateTextInput();
 		} else {
 			super.onBackPressed();
 		}
 	}
 
+	@Override
+	protected void onDestroy() {
+		super.onDestroy();
+		// store list position, so we can restore it when coming back here
+		if (layoutManager != null && adapter != null) {
+			MessageId id = adapter.getFirstVisibleMessageId(layoutManager);
+			getViewModel().storeMessageId(id);
+		}
+	}
+
+	protected void displayItems(List<I> items) {
+		if (items.isEmpty()) {
+			list.showData();
+		} else {
+			adapter.submitList(items, () -> {
+				// do stuff *after* list had been updated
+				scrollAfterListCommitted();
+				updateTextInput();
+			});
+		}
+	}
+
+	/**
+	 * Scrolls to the first visible item last time the activity was open,
+	 * if one exists and this is the first time, the list gets displayed.
+	 * Or scrolls to a locally added item that has just been added to the list.
+	 */
+	private void scrollAfterListCommitted() {
+		MessageId restoredFirstVisibleItemId =
+				getViewModel().getAndResetRestoredMessageId();
+		MessageId scrollToItem =
+				getViewModel().getAndResetScrollToItem();
+		if (restoredFirstVisibleItemId != null) {
+			scrollToItemAtTop(restoredFirstVisibleItemId);
+		} else if (scrollToItem != null) {
+			scrollToItemAtTop(scrollToItem);
+		}
+		scrollListener.updateUnreadButtons(layoutManager);
+	}
+
 	@Override
 	public void onReplyClick(I item) {
-		replyId = item.getId();
+		getViewModel().setReplyId(item.getId());
 		updateTextInput();
 		// FIXME This does not work for a hardware keyboard
 		if (textInput.isKeyboardOpen()) {
-			scrollToItemAtTop(item);
+			scrollToItemAtTop(item.getId());
 		} else {
 			// wait with scrolling until keyboard opened
 			textInput.setOnKeyboardShownListener(() -> {
-				scrollToItemAtTop(item);
+				scrollToItemAtTop(item.getId());
 				textInput.setOnKeyboardShownListener(null);
 			});
 		}
 	}
 
-	@Override
-	public void onSharingInfoUpdated(int total, int online) {
-		setToolbarSubTitle(total, online);
-	}
-
-	@Override
-	public void onInvitationAccepted(ContactId c) {
-		sharingController.add(c);
-		setToolbarSubTitle(sharingController.getTotalCount(),
-				sharingController.getOnlineCount());
-	}
-
-	protected void setToolbarSubTitle(int total, int online) {
+	protected void setToolbarSubTitle(SharingInfo sharingInfo) {
 		ActionBar actionBar = getSupportActionBar();
 		if (actionBar != null) {
-			actionBar.setSubtitle(
-					getString(R.string.shared_with, total, online));
+			actionBar.setSubtitle(getString(R.string.shared_with,
+					sharingInfo.total, sharingInfo.online));
 		}
 	}
 
-	private void scrollToItemAtTop(I item) {
-		int position = adapter.findItemPosition(item);
+	private void scrollToItemAtTop(MessageId messageId) {
+		int position = adapter.findItemPosition(messageId);
 		if (position != NO_POSITION) {
-			layoutManager
-					.scrollToPositionWithOffset(position, 0);
+			layoutManager.scrollToPositionWithOffset(position, 0);
 		}
 	}
 
@@ -327,6 +220,7 @@ public abstract class ThreadListActivity<G extends NamedGroup, I extends ThreadI
 	}
 
 	private void updateTextInput() {
+		MessageId replyId = getViewModel().getReplyId();
 		if (replyId != null) {
 			textInput.setHint(R.string.forum_message_reply_hint);
 			textInput.showSoftKeyboard();
@@ -341,54 +235,14 @@ public abstract class ThreadListActivity<G extends NamedGroup, I extends ThreadI
 			List<AttachmentHeader> headers) {
 		if (isNullOrEmpty(text)) throw new AssertionError();
 
-		I replyItem = adapter.getHighlightedItem();
-		UiResultExceptionHandler<I, DbException> handler =
-				new UiResultExceptionHandler<I, DbException>(this) {
-					@Override
-					public void onResultUi(I result) {
-						addItem(result, true);
-					}
-
-					@Override
-					public void onExceptionUi(DbException exception) {
-						handleException(exception);
-					}
-				};
-		getController().createAndStoreMessage(text, replyItem, handler);
+		MessageId replyId = getViewModel().getReplyId();
+		getViewModel().createAndStoreMessage(text, replyId);
 		textInput.hideSoftKeyboard();
 		textInput.clearText();
-		replyId = null;
+		getViewModel().setReplyId(null);
 		updateTextInput();
 	}
 
 	protected abstract int getMaxTextLength();
 
-	@Override
-	public void onItemReceived(I item) {
-		addItem(item, false);
-	}
-
-	@Override
-	public void onGroupRemoved() {
-		supportFinishAfterTransition();
-	}
-
-	private void addItem(I item, boolean isLocal) {
-		adapter.incrementRevision();
-		MessageId parent = item.getParentId();
-		if (parent != null && !adapter.contains(parent)) {
-			// We've incremented the adapter's revision, so the item will be
-			// loaded when its parent has been loaded
-			LOG.info("Ignoring item with missing parent");
-			return;
-		}
-		adapter.add(item);
-
-		if (isLocal) {
-			scrollToItemAtTop(item);
-		} else {
-			scrollListener.updateUnreadButtons(layoutManager);
-		}
-	}
-
 }

briar-android/src/main/java/org/briarproject/briar/android/threaded/ThreadListController.java

@@ -1,60 +0,0 @@
-package org.briarproject.briar.android.threaded;
-
-import org.briarproject.bramble.api.contact.ContactId;
-import org.briarproject.bramble.api.db.DbException;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
-import org.briarproject.bramble.api.sync.GroupId;
-import org.briarproject.bramble.api.sync.MessageId;
-import org.briarproject.briar.android.controller.ActivityLifecycleController;
-import org.briarproject.briar.android.controller.handler.ExceptionHandler;
-import org.briarproject.briar.android.controller.handler.ResultExceptionHandler;
-import org.briarproject.briar.api.client.NamedGroup;
-
-import java.util.Collection;
-
-import javax.annotation.Nullable;
-
-import androidx.annotation.UiThread;
-
-@NotNullByDefault
-public interface ThreadListController<G extends NamedGroup, I extends ThreadItem>
-		extends ActivityLifecycleController {
-
-	void setGroupId(GroupId groupId);
-
-	void loadNamedGroup(ResultExceptionHandler<G, DbException> handler);
-
-	void loadSharingContacts(
-			ResultExceptionHandler<Collection<ContactId>, DbException> handler);
-
-	void loadItems(
-			ResultExceptionHandler<ThreadItemList<I>, DbException> handler);
-
-	void markItemRead(I item);
-
-	void markItemsRead(Collection<I> items);
-
-	void createAndStoreMessage(String text, @Nullable I parentItem,
-			ResultExceptionHandler<I, DbException> handler);
-
-	void deleteNamedGroup(ExceptionHandler<DbException> handler);
-
-	interface ThreadListListener<I> extends ThreadListDataSource {
-
-		@UiThread
-		void onItemReceived(I item);
-
-		@UiThread
-		void onGroupRemoved();
-
-		@UiThread
-		void onInvitationAccepted(ContactId c);
-	}
-
-	interface ThreadListDataSource {
-
-		@UiThread @Nullable
-		MessageId getFirstVisibleMessageId();
-	}
-
-}

briar-android/src/main/java/org/briarproject/briar/android/threaded/ThreadListControllerImpl.java

@@ -1,273 +0,0 @@
-package org.briarproject.briar.android.threaded;
-
-import android.app.Activity;
-
-import org.briarproject.bramble.api.crypto.CryptoExecutor;
-import org.briarproject.bramble.api.db.DatabaseExecutor;
-import org.briarproject.bramble.api.db.DbException;
-import org.briarproject.bramble.api.event.Event;
-import org.briarproject.bramble.api.event.EventBus;
-import org.briarproject.bramble.api.event.EventListener;
-import org.briarproject.bramble.api.identity.IdentityManager;
-import org.briarproject.bramble.api.lifecycle.LifecycleManager;
-import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
-import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
-import org.briarproject.bramble.api.sync.GroupId;
-import org.briarproject.bramble.api.sync.MessageId;
-import org.briarproject.bramble.api.sync.event.GroupRemovedEvent;
-import org.briarproject.bramble.api.system.Clock;
-import org.briarproject.briar.android.controller.DbControllerImpl;
-import org.briarproject.briar.android.controller.handler.ExceptionHandler;
-import org.briarproject.briar.android.controller.handler.ResultExceptionHandler;
-import org.briarproject.briar.android.threaded.ThreadListController.ThreadListListener;
-import org.briarproject.briar.api.android.AndroidNotificationManager;
-import org.briarproject.briar.api.client.MessageTracker;
-import org.briarproject.briar.api.client.NamedGroup;
-import org.briarproject.briar.api.client.PostHeader;
-import org.briarproject.briar.api.client.ThreadedMessage;
-
-import java.util.Collection;
-import java.util.Collections;
-import java.util.Map;
-import java.util.concurrent.ConcurrentHashMap;
-import java.util.concurrent.Executor;
-import java.util.logging.Logger;
-
-import androidx.annotation.CallSuper;
-
-import static java.util.logging.Level.INFO;
-import static java.util.logging.Level.WARNING;
-import static org.briarproject.bramble.util.LogUtils.logDuration;
-import static org.briarproject.bramble.util.LogUtils.logException;
-import static org.briarproject.bramble.util.LogUtils.now;
-
-@MethodsNotNullByDefault
-@ParametersNotNullByDefault
-public abstract class ThreadListControllerImpl<G extends NamedGroup, I extends ThreadItem, H extends PostHeader, M extends ThreadedMessage, L extends ThreadListListener<I>>
-		extends DbControllerImpl
-		implements ThreadListController<G, I>, EventListener {
-
-	private static final Logger LOG =
-			Logger.getLogger(ThreadListControllerImpl.class.getName());
-
-	private final EventBus eventBus;
-	private final MessageTracker messageTracker;
-	private final Map<MessageId, String> textCache = new ConcurrentHashMap<>();
-
-	private volatile GroupId groupId;
-
-	protected final IdentityManager identityManager;
-	protected final AndroidNotificationManager notificationManager;
-	protected final Executor cryptoExecutor;
-	protected final Clock clock;
-
-	// UI thread
-	protected L listener;
-
-	protected ThreadListControllerImpl(@DatabaseExecutor Executor dbExecutor,
-			LifecycleManager lifecycleManager, IdentityManager identityManager,
-			@CryptoExecutor Executor cryptoExecutor, EventBus eventBus,
-			Clock clock, AndroidNotificationManager notificationManager,
-			MessageTracker messageTracker) {
-		super(dbExecutor, lifecycleManager);
-		this.identityManager = identityManager;
-		this.cryptoExecutor = cryptoExecutor;
-		this.notificationManager = notificationManager;
-		this.clock = clock;
-		this.eventBus = eventBus;
-		this.messageTracker = messageTracker;
-	}
-
-	@Override
-	public void setGroupId(GroupId groupId) {
-		this.groupId = groupId;
-	}
-
-	@CallSuper
-	@SuppressWarnings("unchecked")
-	@Override
-	public void onActivityCreate(Activity activity) {
-		listener = (L) activity;
-	}
-
-	@CallSuper
-	@Override
-	public void onActivityStart() {
-		notificationManager.blockNotification(getGroupId());
-		eventBus.addListener(this);
-	}
-
-	@CallSuper
-	@Override
-	public void onActivityStop() {
-		notificationManager.unblockNotification(getGroupId());
-		eventBus.removeListener(this);
-	}
-
-	@Override
-	public void onActivityDestroy() {
-		MessageId messageId = listener.getFirstVisibleMessageId();
-		if (messageId != null) {
-			dbExecutor.execute(() -> {
-				try {
-					messageTracker.storeMessageId(groupId, messageId);
-				} catch (DbException e) {
-					logException(LOG, WARNING, e);
-				}
-			});
-		}
-	}
-
-	@CallSuper
-	@Override
-	public void eventOccurred(Event e) {
-		if (e instanceof GroupRemovedEvent) {
-			GroupRemovedEvent s = (GroupRemovedEvent) e;
-			if (s.getGroup().getId().equals(getGroupId())) {
-				LOG.info("Group removed");
-				listener.onGroupRemoved();
-			}
-		}
-	}
-
-	@Override
-	public void loadNamedGroup(
-			ResultExceptionHandler<G, DbException> handler) {
-		checkGroupId();
-		runOnDbThread(() -> {
-			try {
-				long start = now();
-				G groupItem = loadNamedGroup();
-				logDuration(LOG, "Loading group", start);
-				handler.onResult(groupItem);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				handler.onException(e);
-			}
-		});
-	}
-
-	@DatabaseExecutor
-	protected abstract G loadNamedGroup() throws DbException;
-
-	@Override
-	public void loadItems(
-			ResultExceptionHandler<ThreadItemList<I>, DbException> handler) {
-		checkGroupId();
-		runOnDbThread(() -> {
-			try {
-				// Load headers
-				long start = now();
-				Collection<H> headers = loadHeaders();
-				logDuration(LOG, "Loading headers", start);
-
-				// Load bodies into cache
-				start = now();
-				for (H header : headers) {
-					if (!textCache.containsKey(header.getId())) {
-						textCache.put(header.getId(),
-								loadMessageText(header));
-					}
-				}
-				logDuration(LOG, "Loading bodies", start);
-
-				// Build and hand over items
-				handler.onResult(buildItems(headers));
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				handler.onException(e);
-			}
-		});
-	}
-
-	@DatabaseExecutor
-	protected abstract Collection<H> loadHeaders() throws DbException;
-
-	@DatabaseExecutor
-	protected abstract String loadMessageText(H header) throws DbException;
-
-	@Override
-	public void markItemRead(I item) {
-		markItemsRead(Collections.singletonList(item));
-	}
-
-	@Override
-	public void markItemsRead(Collection<I> items) {
-		runOnDbThread(() -> {
-			try {
-				long start = now();
-				for (I i : items) {
-					markRead(i.getId());
-				}
-				logDuration(LOG, "Marking read", start);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
-		});
-	}
-
-	@DatabaseExecutor
-	protected abstract void markRead(MessageId id) throws DbException;
-
-	protected void storePost(M msg, String text,
-			ResultExceptionHandler<I, DbException> resultHandler) {
-		runOnDbThread(() -> {
-			try {
-				long start = now();
-				H header = addLocalMessage(msg);
-				textCache.put(msg.getMessage().getId(), text);
-				logDuration(LOG, "Storing message", start);
-				resultHandler.onResult(buildItem(header, text));
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				resultHandler.onException(e);
-			}
-		});
-	}
-
-	@DatabaseExecutor
-	protected abstract H addLocalMessage(M message) throws DbException;
-
-	@Override
-	public void deleteNamedGroup(ExceptionHandler<DbException> handler) {
-		runOnDbThread(() -> {
-			try {
-				long start = now();
-				G groupItem = loadNamedGroup();
-				deleteNamedGroup(groupItem);
-				logDuration(LOG, "Removing group", start);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				handler.onException(e);
-			}
-		});
-	}
-
-	@DatabaseExecutor
-	protected abstract void deleteNamedGroup(G groupItem) throws DbException;
-
-	private ThreadItemList<I> buildItems(Collection<H> headers)
-			throws DbException {
-		ThreadItemList<I> items = new ThreadItemListImpl<>();
-		for (H h : headers) {
-			items.add(buildItem(h, textCache.get(h.getId())));
-		}
-		MessageId msgId = messageTracker.loadStoredMessageId(groupId);
-		if (LOG.isLoggable(INFO))
-			LOG.info("Loaded last top visible message id " + msgId);
-		items.setFirstVisibleId(msgId);
-		return items;
-	}
-
-	protected abstract I buildItem(H header, String text);
-
-	protected GroupId getGroupId() {
-		checkGroupId();
-		return groupId;
-	}
-
-	private void checkGroupId() {
-		if (groupId == null) throw new IllegalStateException();
-	}
-
-}

briar-android/src/main/java/org/briarproject/briar/android/threaded/ThreadListViewModel.java

@@ -0,0 +1,259 @@
+package org.briarproject.briar.android.threaded;
+
+import android.app.Application;
+
+import org.briarproject.bramble.api.crypto.CryptoExecutor;
+import org.briarproject.bramble.api.db.DatabaseExecutor;
+import org.briarproject.bramble.api.db.DbException;
+import org.briarproject.bramble.api.db.Transaction;
+import org.briarproject.bramble.api.db.TransactionManager;
+import org.briarproject.bramble.api.event.Event;
+import org.briarproject.bramble.api.event.EventBus;
+import org.briarproject.bramble.api.event.EventListener;
+import org.briarproject.bramble.api.identity.IdentityManager;
+import org.briarproject.bramble.api.lifecycle.LifecycleManager;
+import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
+import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
+import org.briarproject.bramble.api.sync.GroupId;
+import org.briarproject.bramble.api.sync.MessageId;
+import org.briarproject.bramble.api.sync.event.GroupRemovedEvent;
+import org.briarproject.bramble.api.system.AndroidExecutor;
+import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.briar.android.sharing.SharingController;
+import org.briarproject.briar.android.sharing.SharingController.SharingInfo;
+import org.briarproject.briar.android.viewmodel.DbViewModel;
+import org.briarproject.briar.android.viewmodel.LiveResult;
+import org.briarproject.briar.api.android.AndroidNotificationManager;
+import org.briarproject.briar.api.client.MessageTracker;
+import org.briarproject.briar.api.client.MessageTree;
+import org.briarproject.briar.api.client.PostHeader;
+import org.briarproject.briar.client.MessageTreeImpl;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.concurrent.Executor;
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.logging.Logger;
+
+import javax.annotation.Nullable;
+
+import androidx.annotation.CallSuper;
+import androidx.annotation.UiThread;
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+
+import static java.util.logging.Level.INFO;
+import static java.util.logging.Logger.getLogger;
+import static org.briarproject.bramble.util.LogUtils.logDuration;
+import static org.briarproject.bramble.util.LogUtils.now;
+
+@MethodsNotNullByDefault
+@ParametersNotNullByDefault
+public abstract class ThreadListViewModel<I extends ThreadItem>
+		extends DbViewModel
+		implements EventListener {
+
+	private static final Logger LOG =
+			getLogger(ThreadListViewModel.class.getName());
+
+	protected final IdentityManager identityManager;
+	protected final AndroidNotificationManager notificationManager;
+	protected final SharingController sharingController;
+	protected final Executor cryptoExecutor;
+	protected final Clock clock;
+	private final MessageTracker messageTracker;
+	private final EventBus eventBus;
+
+	@DatabaseExecutor
+	private final MessageTree<I> messageTree = new MessageTreeImpl<>();
+	private final MutableLiveData<LiveResult<List<I>>> items =
+			new MutableLiveData<>();
+	private final MutableLiveData<Boolean> groupRemoved =
+			new MutableLiveData<>();
+	private final AtomicReference<MessageId> scrollToItem =
+			new AtomicReference<>();
+
+	protected volatile GroupId groupId;
+	@Nullable
+	private MessageId replyId;
+	private final AtomicReference<MessageId> storedMessageId =
+			new AtomicReference<>();
+
+	public ThreadListViewModel(Application application,
+			@DatabaseExecutor Executor dbExecutor,
+			LifecycleManager lifecycleManager,
+			TransactionManager db,
+			AndroidExecutor androidExecutor,
+			IdentityManager identityManager,
+			AndroidNotificationManager notificationManager,
+			SharingController sharingController,
+			@CryptoExecutor Executor cryptoExecutor,
+			Clock clock,
+			MessageTracker messageTracker,
+			EventBus eventBus) {
+		super(application, dbExecutor, lifecycleManager, db, androidExecutor);
+		this.identityManager = identityManager;
+		this.notificationManager = notificationManager;
+		this.cryptoExecutor = cryptoExecutor;
+		this.clock = clock;
+		this.sharingController = sharingController;
+		this.messageTracker = messageTracker;
+		this.eventBus = eventBus;
+		this.eventBus.addListener(this);
+	}
+
+	@Override
+	protected void onCleared() {
+		super.onCleared();
+		eventBus.removeListener(this);
+		sharingController.onCleared();
+	}
+
+	/**
+	 * Needs to be called right after initialization,
+	 * before calling any other methods.
+	 */
+	@CallSuper
+	public void setGroupId(GroupId groupId) {
+		this.groupId = groupId;
+		loadStoredMessageId();
+		loadItems();
+		loadSharingContacts();
+	}
+
+	public void blockNotifications() {
+		notificationManager.blockNotification(groupId);
+	}
+
+	public void unblockNotifications() {
+		notificationManager.unblockNotification(groupId);
+	}
+
+	@Override
+	@CallSuper
+	public void eventOccurred(Event e) {
+		if (e instanceof GroupRemovedEvent) {
+			GroupRemovedEvent s = (GroupRemovedEvent) e;
+			if (s.getGroup().getId().equals(groupId)) {
+				LOG.info("Group removed");
+				groupRemoved.setValue(true);
+			}
+		}
+	}
+
+	private void loadStoredMessageId() {
+		runOnDbThreadOrLogException(() -> {
+			storedMessageId.set(messageTracker.loadStoredMessageId(groupId));
+			if (LOG.isLoggable(INFO)) {
+				LOG.info("Loaded last top visible message id " +
+						storedMessageId);
+			}
+		});
+	}
+
+	public abstract void loadItems();
+
+	public abstract void createAndStoreMessage(String text,
+			@Nullable MessageId parentMessageId);
+
+	/**
+	 * Loads the ContactIds of all contacts the group is shared with
+	 * and adds them to {@link SharingController}.
+	 */
+	public abstract void loadSharingContacts();
+
+	@UiThread
+	protected void setItems(LiveResult<List<I>> items) {
+		this.items.setValue(items);
+	}
+
+	@DatabaseExecutor
+	protected <H extends PostHeader> List<I> createItems(
+			Transaction txn, Collection<H> headers, ItemGetter<H, I> itemGetter)
+			throws DbException {
+		long start = now();
+		List<I> items = new ArrayList<>();
+		for (H header : headers) {
+			String text = loadMessageText(txn, header);
+			items.add(itemGetter.getItem(header, text));
+		}
+		logDuration(LOG, "Loading bodies and creating items", start);
+
+		messageTree.clear();
+		messageTree.add(items);
+		return messageTree.depthFirstOrder();
+	}
+
+	/**
+	 * Add a remote item on the UI thread.
+	 * The list will not scroll, but show an unread indicator.
+	 */
+	@UiThread
+	protected void addItem(I item) {
+		messageTree.add(item);
+		items.setValue(new LiveResult<>(messageTree.depthFirstOrder()));
+	}
+
+	/**
+	 * Add a local item from the DB thread.
+	 * The list will scroll to the new item.
+	 */
+	@DatabaseExecutor
+	protected void addItemAsync(I item) {
+		messageTree.add(item);
+		scrollToItem.set(item.getId());
+		items.postValue(new LiveResult<>(messageTree.depthFirstOrder()));
+	}
+
+	@DatabaseExecutor
+	protected abstract String loadMessageText(Transaction txn,
+			PostHeader header) throws DbException;
+
+	@UiThread
+	public void setReplyId(@Nullable MessageId id) {
+		replyId = id;
+	}
+
+	@UiThread
+	@Nullable
+	public MessageId getReplyId() {
+		return replyId;
+	}
+
+	void storeMessageId(@Nullable MessageId messageId) {
+		if (messageId != null) {
+			runOnDbThreadOrLogException(() ->
+					messageTracker.storeMessageId(groupId, messageId));
+		}
+	}
+
+	protected abstract void markItemRead(I item);
+
+	@Nullable
+	MessageId getAndResetRestoredMessageId() {
+		return storedMessageId.getAndSet(null);
+	}
+
+	LiveData<LiveResult<List<I>>> getItems() {
+		return items;
+	}
+
+	LiveData<SharingInfo> getSharingInfo() {
+		return sharingController.getSharingInfo();
+	}
+
+	LiveData<Boolean> getGroupRemoved() {
+		return groupRemoved;
+	}
+
+	@Nullable
+	MessageId getAndResetScrollToItem() {
+		return scrollToItem.getAndSet(null);
+	}
+
+	public interface ItemGetter<H extends PostHeader, I> {
+		I getItem(H header, String text);
+	}
+
+}

briar-android/src/main/java/org/briarproject/briar/android/threaded/ThreadScrollListener.java

@@ -20,15 +20,15 @@ class ThreadScrollListener<I extends ThreadItem>
 	private static final Logger LOG =
 			getLogger(ThreadScrollListener.class.getName());
 
-	private final ThreadListController<?, I> controller;
+	private final ThreadListViewModel<I> viewModel;
 	private final UnreadMessageButton upButton, downButton;
 
 	ThreadScrollListener(ThreadItemAdapter<I> adapter,
-			ThreadListController<?, I> controller,
+			ThreadListViewModel<I> viewModel,
 			UnreadMessageButton upButton,
 			UnreadMessageButton downButton) {
 		super(adapter);
-		this.controller = controller;
+		this.viewModel = viewModel;
 		this.upButton = upButton;
 		this.downButton = downButton;
 	}
@@ -44,7 +44,7 @@ class ThreadScrollListener<I extends ThreadItem>
 	protected void onItemVisible(I item) {
 		if (!item.isRead()) {
 			item.setRead(true);
-			controller.markItemRead(item);
+			viewModel.markItemRead(item);
 		}
 	}
 

briar-android/src/main/java/org/briarproject/briar/android/util/UiUtils.java

@@ -54,7 +54,6 @@ import androidx.fragment.app.FragmentManager;
 import androidx.lifecycle.LifecycleOwner;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.Observer;
-import androidx.vectordrawable.graphics.drawable.VectorDrawableCompat;
 
 import static android.content.Context.KEYGUARD_SERVICE;
 import static android.content.Context.POWER_SERVICE;
@@ -89,6 +88,7 @@ import static androidx.appcompat.app.AppCompatDelegate.MODE_NIGHT_NO;
 import static androidx.appcompat.app.AppCompatDelegate.MODE_NIGHT_YES;
 import static androidx.appcompat.app.AppCompatDelegate.setDefaultNightMode;
 import static androidx.core.content.ContextCompat.getColor;
+import static androidx.core.content.ContextCompat.getDrawable;
 import static androidx.core.content.ContextCompat.getSystemService;
 import static androidx.core.graphics.drawable.DrawableCompat.setTint;
 import static androidx.core.view.ViewCompat.LAYOUT_DIRECTION_RTL;
@@ -436,8 +436,7 @@ public class UiUtils {
 	}
 
 	public static Drawable getDialogIcon(Context ctx, @DrawableRes int resId) {
-		Drawable icon =
-				VectorDrawableCompat.create(ctx.getResources(), resId, null);
+		Drawable icon = getDrawable(ctx, resId);
 		setTint(requireNonNull(icon), getColor(ctx, R.color.color_primary));
 		return icon;
 	}

briar-android/src/main/java/org/briarproject/briar/android/view/BriarRecyclerView.java

@@ -2,6 +2,7 @@ package org.briarproject.briar.android.view;
 
 import android.content.Context;
 import android.content.res.TypedArray;
+import android.graphics.drawable.Drawable;
 import android.os.Handler;
 import android.os.Looper;
 import android.util.AttributeSet;
@@ -52,8 +53,9 @@ public class BriarRecyclerView extends FrameLayout {
 				R.styleable.BriarRecyclerView);
 		isScrollingToEnd = attributes
 				.getBoolean(R.styleable.BriarRecyclerView_scrollToEnd, true);
-		int drawableRes = attributes.getResourceId(R.styleable.BriarRecyclerView_emptyImage, -1);
-		if (drawableRes != -1) setEmptyImage(drawableRes);
+		Drawable drawable = attributes
+				.getDrawable(R.styleable.BriarRecyclerView_emptyImage);
+		if (drawable != null) setEmptyImage(drawable);
 		String emtpyText =
 				attributes.getString(R.styleable.BriarRecyclerView_emptyText);
 		if (emtpyText != null) setEmptyText(emtpyText);
@@ -137,6 +139,11 @@ public class BriarRecyclerView extends FrameLayout {
 		}
 	}
 
+	public void setEmptyImage(Drawable drawable) {
+		if (recyclerView == null) initViews();
+		emptyImage.setImageDrawable(drawable);
+	}
+
 	public void setEmptyImage(@DrawableRes int res) {
 		if (recyclerView == null) initViews();
 		emptyImage.setImageResource(res);

briar-android/src/main/java/org/briarproject/briar/android/view/TextAttachmentController.java

@@ -4,7 +4,6 @@ import android.app.Activity;
 import android.content.ClipData;
 import android.content.Context;
 import android.content.Intent;
-import android.graphics.drawable.Drawable;
 import android.net.Uri;
 import android.os.Parcel;
 import android.os.Parcelable;
@@ -29,7 +28,6 @@ import androidx.customview.view.AbsSavedState;
 import androidx.lifecycle.LifecycleOwner;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.Observer;
-import androidx.vectordrawable.graphics.drawable.VectorDrawableCompat;
 import uk.co.samuelwall.materialtaptargetprompt.MaterialTapTargetPrompt;
 
 import static android.os.Build.VERSION.SDK_INT;
@@ -255,14 +253,12 @@ public class TextAttachmentController extends TextSendController
 
 	public void showImageOnboarding(Activity activity) {
 		int color = resolveColorAttribute(activity, R.attr.colorControlNormal);
-		Drawable drawable = VectorDrawableCompat
-				.create(activity.getResources(), R.drawable.ic_image, null);
 		new MaterialTapTargetPrompt.Builder(activity,
 				R.style.OnboardingDialogTheme).setTarget(sendButton)
 				.setPrimaryText(R.string.dialog_title_image_support)
 				.setSecondaryText(R.string.dialog_message_image_support)
 				.setBackgroundColour(getColor(activity, R.color.briar_primary))
-				.setIconDrawable(drawable)
+				.setIcon(R.drawable.ic_image)
 				.setIconDrawableColourFilter(color)
 				.show();
 	}

briar-android/src/main/java/org/briarproject/briar/android/view/TrustIndicatorView.java

@@ -8,6 +8,7 @@ import org.briarproject.briar.R;
 
 import androidx.annotation.UiThread;
 import androidx.appcompat.widget.AppCompatImageView;
+import androidx.core.content.ContextCompat;
 
 @UiThread
 public class TrustIndicatorView extends AppCompatImageView {
@@ -43,7 +44,7 @@ public class TrustIndicatorView extends AppCompatImageView {
 			default:
 				res = R.drawable.trust_indicator_unknown;
 		}
-		setImageResource(res);
+		setImageDrawable(ContextCompat.getDrawable(getContext(), res));
 		setVisibility(VISIBLE);
 
 		invalidate();

briar-android/src/main/java/org/briarproject/briar/android/viewmodel/DbViewModel.java

@@ -2,9 +2,11 @@ package org.briarproject.briar.android.viewmodel;
 
 import android.app.Application;
 
+import org.briarproject.bramble.api.ThrowingRunnable;
 import org.briarproject.bramble.api.db.DatabaseExecutor;
 import org.briarproject.bramble.api.db.DbCallable;
 import org.briarproject.bramble.api.db.DbException;
+import org.briarproject.bramble.api.db.DbRunnable;
 import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.db.TransactionManager;
 import org.briarproject.bramble.api.lifecycle.LifecycleManager;
@@ -23,6 +25,7 @@ import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.annotation.UiThread;
 import androidx.arch.core.util.Function;
+import androidx.core.util.Consumer;
 import androidx.lifecycle.AndroidViewModel;
 import androidx.lifecycle.LiveData;
 import androidx.recyclerview.widget.RecyclerView;
@@ -57,14 +60,15 @@ public abstract class DbViewModel extends AndroidViewModel {
 	}
 
 	/**
-	 * Runs the given task on the {@link DatabaseExecutor}
-	 * and waits for the DB to open.
+	 * Waits for the DB to open and runs the given task on the
+	 * {@link DatabaseExecutor}.
 	 * <p>
 	 * If you need a list of items to be displayed in a
 	 * {@link RecyclerView.Adapter},
 	 * use {@link #loadList(DbCallable, UiConsumer)} instead.
 	 */
-	protected void runOnDbThread(Runnable task) {
+	protected void runOnDbThread(ThrowingRunnable<Exception> task,
+			Consumer<Exception> err) {
 		dbExecutor.execute(() -> {
 			try {
 				lifecycleManager.waitForDatabase();
@@ -72,10 +76,63 @@ public abstract class DbViewModel extends AndroidViewModel {
 			} catch (InterruptedException e) {
 				LOG.warning("Interrupted while waiting for database");
 				Thread.currentThread().interrupt();
+			} catch (Exception e) {
+				err.accept(e);
 			}
 		});
 	}
 
+	/**
+	 * Waits for the DB to open and runs the given task on the
+	 * {@link DatabaseExecutor}.
+	 * <p>
+	 * If you need a list of items to be displayed in a
+	 * {@link RecyclerView.Adapter},
+	 * use {@link #loadList(DbCallable, UiConsumer)} instead.
+	 */
+	protected void runOnDbThread(boolean readOnly,
+			DbRunnable<Exception> task, Consumer<Exception> err) {
+		dbExecutor.execute(() -> {
+			try {
+				lifecycleManager.waitForDatabase();
+				db.transaction(readOnly, task);
+			} catch (InterruptedException e) {
+				LOG.warning("Interrupted while waiting for database");
+				Thread.currentThread().interrupt();
+			} catch (Exception e) {
+				err.accept(e);
+			}
+		});
+	}
+
+	/**
+	 * Waits for the DB to open and runs the given task on the
+	 * {@link DatabaseExecutor}. If the task throws a {@link DbException}
+	 * it's caught and logged.
+	 * <p>
+	 * If you need a list of items to be displayed in a
+	 * {@link RecyclerView.Adapter},
+	 * use {@link #loadList(DbCallable, UiConsumer)} instead.
+	 */
+	protected void runOnDbThreadOrLogException(boolean readOnly,
+			DbRunnable<Exception> task) {
+		runOnDbThread(readOnly, task, e -> logException(LOG, WARNING, e));
+	}
+
+	/**
+	 * Waits for the DB to open and runs the given task on the
+	 * {@link DatabaseExecutor}. If the task throws a {@link DbException}
+	 * it's caught and logged.
+	 * <p>
+	 * If you need a list of items to be displayed in a
+	 * {@link RecyclerView.Adapter},
+	 * use {@link #loadList(DbCallable, UiConsumer)} instead.
+	 */
+	protected void runOnDbThreadOrLogException(
+			ThrowingRunnable<Exception> task) {
+		runOnDbThread(task, e -> logException(LOG, WARNING, e));
+	}
+
 	/**
 	 * Loads a list of items on the {@link DatabaseExecutor} within a single
 	 * {@link Transaction} and publishes it as a {@link LiveResult}

briar-android/src/main/res/drawable-anydpi-v24/notification_lock.xml

@@ -1,15 +0,0 @@
-<vector xmlns:android="http://schemas.android.com/apk/res/android"
-    android:width="24dp"
-    android:height="24dp"
-    android:viewportWidth="24"
-    android:viewportHeight="24"
-    android:tint="#FFFFFF">
-  <group android:scaleX="0.92"
-      android:scaleY="0.92"
-      android:translateX="0.96"
-      android:translateY="0.96">
-    <path
-        android:fillColor="@android:color/white"
-        android:pathData="M18,8h-1L17,6c0,-2.76 -2.24,-5 -5,-5S7,3.24 7,6v2L6,8c-1.1,0 -2,0.9 -2,2v10c0,1.1 0.9,2 2,2h12c1.1,0 2,-0.9 2,-2L20,10c0,-1.1 -0.9,-2 -2,-2zM12,17c-1.1,0 -2,-0.9 -2,-2s0.9,-2 2,-2 2,0.9 2,2 -0.9,2 -2,2zM15.1,8L8.9,8L8.9,6c0,-1.71 1.39,-3.1 3.1,-3.1 1.71,0 3.1,1.39 3.1,3.1v2z"/>
-  </group>
-</vector>

briar-android/src/main/res/drawable-anydpi-v24/notification_signout.xml

@@ -1,15 +0,0 @@
-<vector xmlns:android="http://schemas.android.com/apk/res/android"
-    android:width="24dp"
-    android:height="24dp"
-    android:viewportWidth="24"
-    android:viewportHeight="24"
-    android:tint="#FFFFFF">
-  <group android:scaleX="0.92"
-      android:scaleY="0.92"
-      android:translateX="0.96"
-      android:translateY="0.96">
-    <path
-        android:fillColor="#FF000000"
-        android:pathData="M16,17V14H9V10H16V7L21,12L16,17M14,2A2,2 0,0 1,16 4V6H14V4H5V20H14V18H16V20A2,2 0,0 1,14 22H5A2,2 0,0 1,3 20V4A2,2 0,0 1,5 2H14Z"/>
-  </group>
-</vector>

briar-android/src/main/res/drawable/notification_blog.xml

@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <vector xmlns:android="http://schemas.android.com/apk/res/android"
-	android:width="24dp"
-	android:height="24dp"
-	android:viewportWidth="24.0"
-	android:viewportHeight="24.0">
+        android:width="24dp"
+        android:height="24dp"
+        android:viewportHeight="24.0"
+        android:viewportWidth="24.0">
 	<path
 		android:fillColor="#FFFFFFFF"
-		android:pathData="M13,12h7v1.5h-7zM13,9.5h7L20,11h-7zM13,14.5h7L20,16h-7zM21,4L3,4c-1.1,0 -2,0.9 -2,2v13c0,1.1 0.9,2 2,2h18c1.1,0 2,-0.9 2,-2L23,6c0,-1.1 -0.9,-2 -2,-2zM21,19h-9L12,6h9v13z" />
+		android:pathData="M13,12h7v1.5h-7zM13,9.5h7L20,11h-7zM13,14.5h7L20,16h-7zM21,4L3,4c-1.1,0 -2,0.9 -2,2v13c0,1.1 0.9,2 2,2h18c1.1,0 2,-0.9 2,-2L23,6c0,-1.1 -0.9,-2 -2,-2zM21,19h-9L12,6h9v13z"/>
 </vector>

briar-android/src/main/res/drawable/notification_contact_added.xml

@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <vector xmlns:android="http://schemas.android.com/apk/res/android"
-	android:width="24dp"
-	android:height="24dp"
-	android:viewportWidth="24.0"
-	android:viewportHeight="24.0">
+        android:width="24dp"
+        android:height="24dp"
+        android:viewportHeight="24.0"
+        android:viewportWidth="24.0">
 	<path
 		android:fillColor="#FFFFFFFF"
-		android:pathData="M20,0L4,0v2h16L20,0zM4,24h16v-2L4,22v2zM20,4L4,4c-1.1,0 -2,0.9 -2,2v12c0,1.1 0.9,2 2,2h16c1.1,0 2,-0.9 2,-2L22,6c0,-1.1 -0.9,-2 -2,-2zM12,6.75c1.24,0 2.25,1.01 2.25,2.25s-1.01,2.25 -2.25,2.25S9.75,10.24 9.75,9 10.76,6.75 12,6.75zM17,17L7,17v-1.5c0,-1.67 3.33,-2.5 5,-2.5s5,0.83 5,2.5L17,17z" />
+		android:pathData="M20,0L4,0v2h16L20,0zM4,24h16v-2L4,22v2zM20,4L4,4c-1.1,0 -2,0.9 -2,2v12c0,1.1 0.9,2 2,2h16c1.1,0 2,-0.9 2,-2L22,6c0,-1.1 -0.9,-2 -2,-2zM12,6.75c1.24,0 2.25,1.01 2.25,2.25s-1.01,2.25 -2.25,2.25S9.75,10.24 9.75,9 10.76,6.75 12,6.75zM17,17L7,17v-1.5c0,-1.67 3.33,-2.5 5,-2.5s5,0.83 5,2.5L17,17z"/>
 </vector>

briar-android/src/main/res/drawable/notification_private_group.xml

@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <vector xmlns:android="http://schemas.android.com/apk/res/android"
-	android:width="24dp"
-	android:height="24dp"
-	android:viewportWidth="24.0"
-	android:viewportHeight="24.0">
+        android:width="24dp"
+        android:height="24dp"
+        android:viewportHeight="24.0"
+        android:viewportWidth="24.0">
 	<path
 		android:fillColor="#FFFFFFFF"
-		android:pathData="M16,11c1.66,0 2.99,-1.34 2.99,-3S17.66,5 16,5c-1.66,0 -3,1.34 -3,3s1.34,3 3,3zM8,11c1.66,0 2.99,-1.34 2.99,-3S9.66,5 8,5C6.34,5 5,6.34 5,8s1.34,3 3,3zM8,13c-2.33,0 -7,1.17 -7,3.5L1,19h14v-2.5c0,-2.33 -4.67,-3.5 -7,-3.5zM16,13c-0.29,0 -0.62,0.02 -0.97,0.05 1.16,0.84 1.97,1.97 1.97,3.45L17,19h6v-2.5c0,-2.33 -4.67,-3.5 -7,-3.5z" />
+		android:pathData="M16,11c1.66,0 2.99,-1.34 2.99,-3S17.66,5 16,5c-1.66,0 -3,1.34 -3,3s1.34,3 3,3zM8,11c1.66,0 2.99,-1.34 2.99,-3S9.66,5 8,5C6.34,5 5,6.34 5,8s1.34,3 3,3zM8,13c-2.33,0 -7,1.17 -7,3.5L1,19h14v-2.5c0,-2.33 -4.67,-3.5 -7,-3.5zM16,13c-0.29,0 -0.62,0.02 -0.97,0.05 1.16,0.84 1.97,1.97 1.97,3.45L17,19h6v-2.5c0,-2.33 -4.67,-3.5 -7,-3.5z"/>
 </vector>

briar-android/src/main/res/drawable/notification_private_message.xml

@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <vector xmlns:android="http://schemas.android.com/apk/res/android"
-	android:width="24dp"
-	android:height="24dp"
-	android:viewportWidth="24.0"
-	android:viewportHeight="24.0">
+        android:width="24dp"
+        android:height="24dp"
+        android:viewportHeight="24.0"
+        android:viewportWidth="24.0">
 	<path
 		android:fillColor="#FFFFFFFF"
-		android:pathData="M20,2L4,2c-1.1,0 -1.99,0.9 -1.99,2L2,22l4,-4h14c1.1,0 2,-0.9 2,-2L22,4c0,-1.1 -0.9,-2 -2,-2zM18,14L6,14v-2h12v2zM18,11L6,11L6,9h12v2zM18,8L6,8L6,6h12v2z" />
+		android:pathData="M20,2L4,2c-1.1,0 -1.99,0.9 -1.99,2L2,22l4,-4h14c1.1,0 2,-0.9 2,-2L22,4c0,-1.1 -0.9,-2 -2,-2zM18,14L6,14v-2h12v2zM18,11L6,11L6,9h12v2zM18,8L6,8L6,6h12v2z"/>
 </vector>