Migrate BlogController to BlogViewModel

briar-android/src/main/java/org/briarproject/briar/android/blog/BaseController.java

@@ -1,48 +0,0 @@
-package org.briarproject.briar.android.blog;
-
-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.handler.ExceptionHandler;
-import org.briarproject.briar.android.controller.handler.ResultExceptionHandler;
-import org.briarproject.briar.api.blog.BlogPostHeader;
-
-import java.util.List;
-
-import javax.annotation.Nullable;
-
-import androidx.annotation.UiThread;
-
-@NotNullByDefault
-interface BaseController {
-
-	@UiThread
-	void onStart();
-
-	@UiThread
-	void onStop();
-
-	void loadBlogPosts(GroupId g,
-			ResultExceptionHandler<List<BlogPostItem>, DbException> handler);
-
-	void loadBlogPost(BlogPostHeader header,
-			ResultExceptionHandler<BlogPostItem, DbException> handler);
-
-	void loadBlogPost(GroupId g, MessageId m,
-			ResultExceptionHandler<BlogPostItem, DbException> handler);
-
-	void repeatPost(BlogPostItem item, @Nullable String comment,
-			ExceptionHandler<DbException> handler);
-
-	@NotNullByDefault
-	interface BlogListener {
-
-		@UiThread
-		void onBlogPostAdded(BlogPostHeader header, boolean local);
-
-		@UiThread
-		void onBlogRemoved();
-	}
-
-}

briar-android/src/main/java/org/briarproject/briar/android/blog/BaseControllerImpl.java

@@ -1,61 +1,28 @@
 package org.briarproject.briar.android.blog;
 
 import org.briarproject.bramble.api.db.DatabaseExecutor;
-import org.briarproject.bramble.api.db.DbException;
 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.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.briar.android.controller.DbControllerImpl;
-import org.briarproject.briar.android.controller.handler.ExceptionHandler;
-import org.briarproject.briar.android.controller.handler.ResultExceptionHandler;
 import org.briarproject.briar.api.android.AndroidNotificationManager;
-import org.briarproject.briar.api.blog.Blog;
-import org.briarproject.briar.api.blog.BlogCommentHeader;
 import org.briarproject.briar.api.blog.BlogManager;
-import org.briarproject.briar.api.blog.BlogPostHeader;
-import org.briarproject.briar.util.HtmlUtils;
 
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.List;
-import java.util.Map;
-import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.Executor;
-import java.util.logging.Logger;
-
-import javax.annotation.Nullable;
-
-import androidx.annotation.CallSuper;
-
-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;
-import static org.briarproject.briar.util.HtmlUtils.ARTICLE;
 
 @MethodsNotNullByDefault
 @ParametersNotNullByDefault
 abstract class BaseControllerImpl extends DbControllerImpl
-		implements BaseController, EventListener {
+		implements EventListener {
-
-	private static final Logger LOG =
-			Logger.getLogger(BaseControllerImpl.class.getName());
 
 	protected final EventBus eventBus;
 	protected final AndroidNotificationManager notificationManager;
 	protected final IdentityManager identityManager;
 	protected final BlogManager blogManager;
 
-	private final Map<MessageId, String> textCache = new ConcurrentHashMap<>();
-	private final Map<MessageId, BlogPostHeader> headerCache =
-			new ConcurrentHashMap<>();
-
 	BaseControllerImpl(@DatabaseExecutor Executor dbExecutor,
 			LifecycleManager lifecycleManager, EventBus eventBus,
 			AndroidNotificationManager notificationManager,
@@ -67,144 +34,4 @@ abstract class BaseControllerImpl extends DbControllerImpl
 		this.blogManager = blogManager;
 	}
 
-	@Override
-	@CallSuper
-	public void onStart() {
-		eventBus.addListener(this);
-	}
-
-	@Override
-	@CallSuper
-	public void onStop() {
-		eventBus.removeListener(this);
-	}
-
-	@Override
-	public void loadBlogPosts(GroupId groupId,
-			ResultExceptionHandler<List<BlogPostItem>, DbException> handler) {
-		runOnDbThread(() -> {
-			try {
-				List<BlogPostItem> items = loadItems(groupId);
-				handler.onResult(items);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				handler.onException(e);
-			}
-		});
-	}
-
-	List<BlogPostItem> loadItems(GroupId groupId) throws DbException {
-		long start = now();
-		Collection<BlogPostHeader> headers =
-				blogManager.getPostHeaders(groupId);
-		logDuration(LOG, "Loading headers", start);
-		List<BlogPostItem> items = new ArrayList<>(headers.size());
-		start = now();
-		for (BlogPostHeader h : headers) {
-			headerCache.put(h.getId(), h);
-			BlogPostItem item = getItem(h);
-			items.add(item);
-		}
-		logDuration(LOG, "Loading bodies", start);
-		return items;
-	}
-
-	@Override
-	public void loadBlogPost(BlogPostHeader header,
-			ResultExceptionHandler<BlogPostItem, DbException> handler) {
-
-		String text = textCache.get(header.getId());
-		if (text != null) {
-			LOG.info("Loaded text from cache");
-			handler.onResult(new BlogPostItem(header, text));
-			return;
-		}
-		runOnDbThread(() -> {
-			try {
-				long start = now();
-				BlogPostItem item = getItem(header);
-				logDuration(LOG, "Loading text", start);
-				handler.onResult(item);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				handler.onException(e);
-			}
-		});
-	}
-
-	@Override
-	public void loadBlogPost(GroupId g, MessageId m,
-			ResultExceptionHandler<BlogPostItem, DbException> handler) {
-
-		BlogPostHeader header = headerCache.get(m);
-		if (header != null) {
-			LOG.info("Loaded header from cache");
-			loadBlogPost(header, handler);
-			return;
-		}
-		runOnDbThread(() -> {
-			try {
-				long start = now();
-				BlogPostHeader header1 = getPostHeader(g, m);
-				BlogPostItem item = getItem(header1);
-				logDuration(LOG, "Loading post", start);
-				handler.onResult(item);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				handler.onException(e);
-			}
-		});
-	}
-
-	@Override
-	public void repeatPost(BlogPostItem item, @Nullable String comment,
-			ExceptionHandler<DbException> handler) {
-		runOnDbThread(() -> {
-			try {
-				LocalAuthor a = identityManager.getLocalAuthor();
-				Blog b = blogManager.getPersonalBlog(a);
-				BlogPostHeader h = item.getHeader();
-				blogManager.addLocalComment(a, b.getId(), comment, h);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				handler.onException(e);
-			}
-		});
-	}
-
-	private BlogPostHeader getPostHeader(GroupId g, MessageId m)
-			throws DbException {
-		BlogPostHeader header = headerCache.get(m);
-		if (header == null) {
-			header = blogManager.getPostHeader(g, m);
-			headerCache.put(m, header);
-		}
-		return header;
-	}
-
-	@DatabaseExecutor
-	private BlogPostItem getItem(BlogPostHeader h) throws DbException {
-		String text;
-		if (h instanceof BlogCommentHeader) {
-			BlogCommentHeader c = (BlogCommentHeader) h;
-			BlogCommentItem item = new BlogCommentItem(c);
-			text = getPostText(item.getPostHeader().getId());
-			item.setText(text);
-			return item;
-		} else {
-			text = getPostText(h.getId());
-			return new BlogPostItem(h, text);
-		}
-	}
-
-	@DatabaseExecutor
-	private String getPostText(MessageId m) throws DbException {
-		String text = textCache.get(m);
-		if (text == null) {
-			text = HtmlUtils.clean(blogManager.getPostText(m), ARTICLE);
-			textCache.put(m, text);
-		}
-		return text;
-	}
-
 }

briar-android/src/main/java/org/briarproject/briar/android/blog/BaseViewModel.java

@@ -4,7 +4,6 @@ import android.app.Application;
 
 import org.briarproject.bramble.api.db.DatabaseExecutor;
 import org.briarproject.bramble.api.db.DbException;
-import org.briarproject.bramble.api.db.NoSuchMessageException;
 import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.db.TransactionManager;
 import org.briarproject.bramble.api.event.Event;
@@ -19,6 +18,7 @@ import org.briarproject.bramble.api.sync.MessageId;
 import org.briarproject.bramble.api.system.AndroidExecutor;
 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.blog.Blog;
 import org.briarproject.briar.api.blog.BlogCommentHeader;
 import org.briarproject.briar.api.blog.BlogManager;
@@ -26,6 +26,7 @@ import org.briarproject.briar.api.blog.BlogPostHeader;
 import org.briarproject.briar.util.HtmlUtils;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
@@ -35,11 +36,10 @@ import java.util.logging.Logger;
 import javax.annotation.Nullable;
 import javax.inject.Inject;
 
+import androidx.annotation.UiThread;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.MutableLiveData;
-import androidx.lifecycle.Transformations;
 
-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;
@@ -50,20 +50,23 @@ import static org.briarproject.briar.util.HtmlUtils.ARTICLE;
 @NotNullByDefault
 public class BaseViewModel extends DbViewModel implements EventListener {
 
-	private static Logger LOG = getLogger(BaseViewModel.class.getName());
+	private static final Logger LOG = getLogger(BaseViewModel.class.getName());
 
 	protected final TransactionManager db;
 	private final EventBus eventBus;
 	protected final IdentityManager identityManager;
+	protected final AndroidNotificationManager notificationManager;
 	protected final BlogManager blogManager;
 
-	protected final MutableLiveData<LiveResult<List<BlogPostItem>>> blogPosts =
+	private final MutableLiveData<LiveResult<List<BlogPostItem>>> blogPosts =
 			new MutableLiveData<>();
 
 	// TODO do we still need those caches?
 	private final Map<MessageId, String> textCache = new ConcurrentHashMap<>();
 	private final Map<MessageId, BlogPostHeader> headerCache =
 			new ConcurrentHashMap<>();
+	@Nullable
+	private Boolean postAddedWasLocal = null;
 
 	@Inject
 	BaseViewModel(Application application,
@@ -73,11 +76,13 @@ public class BaseViewModel extends DbViewModel implements EventListener {
 			AndroidExecutor androidExecutor,
 			EventBus eventBus,
 			IdentityManager identityManager,
+			AndroidNotificationManager notificationManager,
 			BlogManager blogManager) {
 		super(application, dbExecutor, lifecycleManager, db, androidExecutor);
 		this.db = db;
 		this.eventBus = eventBus;
 		this.identityManager = identityManager;
+		this.notificationManager = notificationManager;
 		this.blogManager = blogManager;
 
 		eventBus.addListener(this);
@@ -93,10 +98,6 @@ public class BaseViewModel extends DbViewModel implements EventListener {
 	public void eventOccurred(Event e) {
 	}
 
-	void loadItems(GroupId groupId) {
-		loadList(txn -> loadBlogPosts(txn, groupId), blogPosts::setValue);
-	}
-
 	@DatabaseExecutor
 	protected List<BlogPostItem> loadBlogPosts(Transaction txn, GroupId groupId)
 			throws DbException {
@@ -148,9 +149,9 @@ public class BaseViewModel extends DbViewModel implements EventListener {
 		runOnDbThread(() -> {
 			try {
 				long start = now();
-				BlogPostHeader header1 = getPostHeader(g, m);
+				BlogPostHeader header = getPostHeader(g, m);
 				BlogPostItem item = db.transactionWithResult(true, txn ->
-						getItem(txn, header1)
+						getItem(txn, header)
 				);
 				logDuration(LOG, "Loading post", start);
 				result.postValue(new LiveResult<>(item));
@@ -173,6 +174,31 @@ public class BaseViewModel extends DbViewModel implements EventListener {
 		return header;
 	}
 
+	@UiThread
+	protected void updateBlogPosts(LiveResult<List<BlogPostItem>> posts) {
+		blogPosts.setValue(posts);
+	}
+
+	protected void onBlogPostAdded(BlogPostHeader header, boolean local) {
+		postAddedWasLocal = local;
+		runOnDbThread(() -> {
+			try {
+				db.transaction(true, txn -> {
+					BlogPostItem item = getItem(txn, header);
+					txn.attach(() -> {
+						List<BlogPostItem> items = addListItem(blogPosts, item);
+						if (items != null) {
+							Collections.sort(items);
+							blogPosts.setValue(new LiveResult<>(items));
+						}
+					});
+				});
+			} catch (DbException e) {
+				logException(LOG, WARNING, e);
+			}
+		});
+	}
+
 	void repeatPost(BlogPostItem item, @Nullable String comment) {
 		runOnDbThread(() -> {
 			try {
@@ -186,34 +212,17 @@ public class BaseViewModel extends DbViewModel implements EventListener {
 		});
 	}
 
-	LiveData<LiveResult<List<BlogPostItem>>> getAllBlogPosts() {
+	LiveData<LiveResult<List<BlogPostItem>>> getBlogPosts() {
 		return blogPosts;
 	}
 
-	LiveData<LiveResult<List<BlogPostItem>>> getBlogPosts(GroupId g) {
+	@UiThread
-		return Transformations.map(blogPosts, result -> {
+	@Nullable
-			List<BlogPostItem> allPosts = result.getResultOrNull();
+	Boolean getPostAddedWasLocalAndReset() {
-			if (allPosts == null) return result;
+		if (postAddedWasLocal == null) return null;
-			List<BlogPostItem> groupPosts = new ArrayList<>();
+		boolean wasLocal = postAddedWasLocal;
-			for (BlogPostItem item : allPosts) {
+		postAddedWasLocal = null;
-				if (item.getGroupId().equals(g)) groupPosts.add(item);
+		return wasLocal;
-			}
-			return new LiveResult<>(groupPosts);
-		});
-	}
-
-	LiveData<LiveResult<BlogPostItem>> getBlogPost(MessageId m) {
-		return Transformations.map(blogPosts, result -> {
-			List<BlogPostItem> allPosts = result.getResultOrNull();
-			if (allPosts == null) {
-				Exception e = requireNonNull(result.getException());
-				return new LiveResult<>(e);
-			}
-			for (BlogPostItem item : allPosts) {
-				if (item.getId().equals(m)) return new LiveResult<>(item);
-			}
-			return new LiveResult<>(new NoSuchMessageException());
-		});
 	}
 
 }

briar-android/src/main/java/org/briarproject/briar/android/blog/BlogActivity.java

@@ -16,15 +16,27 @@ import javax.annotation.Nullable;
 import javax.inject.Inject;
 
 import androidx.appcompat.widget.Toolbar;
+import androidx.lifecycle.ViewModelProvider;
 
 @MethodsNotNullByDefault
 @ParametersNotNullByDefault
 public class BlogActivity extends BriarActivity
 		implements BaseFragmentListener {
 
+	@Inject
+	ViewModelProvider.Factory viewModelFactory;
 	@Inject
 	BlogController blogController;
 
+	private BlogViewModel viewModel;
+
+	@Override
+	public void injectActivity(ActivityComponent component) {
+		component.inject(this);
+		viewModel = new ViewModelProvider(this, viewModelFactory)
+				.get(BlogViewModel.class);
+	}
+
 	@Override
 	public void onCreate(@Nullable Bundle state) {
 		super.onCreate(state);
@@ -35,6 +47,7 @@ public class BlogActivity extends BriarActivity
 		if (b == null) throw new IllegalStateException("No group ID in intent");
 		GroupId groupId = new GroupId(b);
 		blogController.setGroupId(groupId);
+		viewModel.setGroupId(groupId);
 
 		setContentView(R.layout.activity_fragment_container_toolbar);
 		Toolbar toolbar = setUpCustomToolbar(false);
@@ -54,9 +67,4 @@ public class BlogActivity extends BriarActivity
 		}
 	}
 
-	@Override
-	public void injectActivity(ActivityComponent component) {
-		component.inject(this);
-	}
-
 }

briar-android/src/main/java/org/briarproject/briar/android/blog/BlogController.java

@@ -4,44 +4,16 @@ 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.handler.ResultExceptionHandler;
 
 import java.util.Collection;
-import java.util.List;
-
-import androidx.annotation.UiThread;
 
 @NotNullByDefault
-public interface BlogController extends BaseController {
+public interface BlogController  {
 
 	void setGroupId(GroupId g);
 
-	@UiThread
-	void setBlogSharingListener(BlogSharingListener listener);
-
-	@UiThread
-	void unsetBlogSharingListener(BlogSharingListener listener);
-
-	void loadBlogPosts(
-			ResultExceptionHandler<List<BlogPostItem>, DbException> handler);
-
-	void loadBlogPost(MessageId m,
-			ResultExceptionHandler<BlogPostItem, DbException> handler);
-
-	void loadBlog(ResultExceptionHandler<BlogItem, DbException> handler);
-
-	void deleteBlog(ResultExceptionHandler<Void, DbException> handler);
-
 	void loadSharingContacts(
 			ResultExceptionHandler<Collection<ContactId>, DbException> handler);
 
-	interface BlogSharingListener extends BlogListener {
-		@UiThread
-		void onBlogInvitationAccepted(ContactId c);
-
-		@UiThread
-		void onBlogLeft(ContactId c);
-	}
-
 }

briar-android/src/main/java/org/briarproject/briar/android/blog/BlogControllerImpl.java

@@ -10,38 +10,25 @@ 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.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.sync.event.GroupRemovedEvent;
 import org.briarproject.briar.android.controller.ActivityLifecycleController;
 import org.briarproject.briar.android.controller.handler.ResultExceptionHandler;
 import org.briarproject.briar.api.android.AndroidNotificationManager;
-import org.briarproject.briar.api.blog.Blog;
-import org.briarproject.briar.api.blog.BlogInvitationResponse;
 import org.briarproject.briar.api.blog.BlogManager;
 import org.briarproject.briar.api.blog.BlogSharingManager;
-import org.briarproject.briar.api.blog.event.BlogInvitationResponseReceivedEvent;
-import org.briarproject.briar.api.blog.event.BlogPostAddedEvent;
-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.inject.Inject;
 
-import androidx.annotation.Nullable;
-
 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
@@ -53,10 +40,6 @@ class BlogControllerImpl extends BaseControllerImpl
 
 	private final BlogSharingManager blogSharingManager;
 
-	// UI thread
-	@Nullable
-	private BlogSharingListener listener;
-
 	private volatile GroupId groupId = null;
 
 	@Inject
@@ -76,15 +59,10 @@ class BlogControllerImpl extends BaseControllerImpl
 
 	@Override
 	public void onActivityStart() {
-		super.onStart();
-		notificationManager.blockNotification(groupId);
-		notificationManager.clearBlogPostNotification(groupId);
 	}
 
 	@Override
 	public void onActivityStop() {
-		super.onStop();
-		notificationManager.unblockNotification(groupId);
 	}
 
 	@Override
@@ -96,99 +74,9 @@ class BlogControllerImpl extends BaseControllerImpl
 		groupId = g;
 	}
 
-	@Override
-	public void setBlogSharingListener(BlogSharingListener listener) {
-		this.listener = listener;
-	}
-
-	@Override
-	public void unsetBlogSharingListener(BlogSharingListener listener) {
-		if (this.listener == listener) this.listener = null;
-	}
-
 	@Override
 	public void eventOccurred(Event e) {
-		if (groupId == null || listener == null)
-			throw new IllegalStateException();
-		if (e instanceof BlogPostAddedEvent) {
-			BlogPostAddedEvent b = (BlogPostAddedEvent) e;
-			if (b.getGroupId().equals(groupId)) {
-				LOG.info("Blog post added");
-				listener.onBlogPostAdded(b.getHeader(), b.isLocal());
-			}
-		} else if (e instanceof BlogInvitationResponseReceivedEvent) {
-			BlogInvitationResponseReceivedEvent b =
-					(BlogInvitationResponseReceivedEvent) e;
-			BlogInvitationResponse r = b.getMessageHeader();
-			if (r.getShareableId().equals(groupId) && r.wasAccepted()) {
-				LOG.info("Blog invitation accepted");
-				listener.onBlogInvitationAccepted(b.getContactId());
-			}
-		} else if (e instanceof ContactLeftShareableEvent) {
-			ContactLeftShareableEvent s = (ContactLeftShareableEvent) e;
-			if (s.getGroupId().equals(groupId)) {
-				LOG.info("Blog left by contact");
-				listener.onBlogLeft(s.getContactId());
-			}
-		} else if (e instanceof GroupRemovedEvent) {
-			GroupRemovedEvent g = (GroupRemovedEvent) e;
-			if (g.getGroup().getId().equals(groupId)) {
-				LOG.info("Blog removed");
-				listener.onBlogRemoved();
-			}
-		}
-	}
 
-	@Override
-	public void loadBlogPosts(
-			ResultExceptionHandler<List<BlogPostItem>, DbException> handler) {
-		if (groupId == null) throw new IllegalStateException();
-		loadBlogPosts(groupId, handler);
-	}
-
-	@Override
-	public void loadBlogPost(MessageId m,
-			ResultExceptionHandler<BlogPostItem, DbException> handler) {
-		if (groupId == null) throw new IllegalStateException();
-		loadBlogPost(groupId, m, handler);
-	}
-
-	@Override
-	public void loadBlog(
-			ResultExceptionHandler<BlogItem, DbException> handler) {
-		if (groupId == null) throw new IllegalStateException();
-		runOnDbThread(() -> {
-			try {
-				long start = now();
-				LocalAuthor a = identityManager.getLocalAuthor();
-				Blog b = blogManager.getBlog(groupId);
-				boolean ours = a.getId().equals(b.getAuthor().getId());
-				boolean removable = blogManager.canBeRemoved(b);
-				BlogItem blog = new BlogItem(b, ours, removable);
-				logDuration(LOG, "Loading blog", start);
-				handler.onResult(blog);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				handler.onException(e);
-			}
-		});
-	}
-
-	@Override
-	public void deleteBlog(ResultExceptionHandler<Void, DbException> handler) {
-		if (groupId == null) throw new IllegalStateException();
-		runOnDbThread(() -> {
-			try {
-				long start = now();
-				Blog b = blogManager.getBlog(groupId);
-				blogManager.removeBlog(b);
-				logDuration(LOG, "Removing blog", start);
-				handler.onResult(null);
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-				handler.onException(e);
-			}
-		});
 	}
 
 	@Override

briar-android/src/main/java/org/briarproject/briar/android/blog/BlogFragment.java

@@ -1,6 +1,5 @@
 package org.briarproject.briar.android.blog;
 
-import android.content.DialogInterface;
 import android.content.Intent;
 import android.os.Bundle;
 import android.os.Parcelable;
@@ -21,7 +20,6 @@ import org.briarproject.bramble.api.sync.GroupId;
 import org.briarproject.briar.R;
 import org.briarproject.briar.android.activity.ActivityComponent;
 import org.briarproject.briar.android.activity.BriarActivity;
-import org.briarproject.briar.android.blog.BlogController.BlogSharingListener;
 import org.briarproject.briar.android.controller.SharingController;
 import org.briarproject.briar.android.controller.handler.UiResultExceptionHandler;
 import org.briarproject.briar.android.fragment.BaseFragment;
@@ -30,7 +28,6 @@ import org.briarproject.briar.android.sharing.ShareBlogActivity;
 import org.briarproject.briar.android.util.BriarSnackbarBuilder;
 import org.briarproject.briar.android.view.BriarRecyclerView;
 import org.briarproject.briar.android.widget.LinkDialogFragment;
-import org.briarproject.briar.api.blog.BlogPostHeader;
 
 import java.util.Collection;
 import java.util.List;
@@ -41,6 +38,7 @@ import androidx.annotation.Nullable;
 import androidx.annotation.UiThread;
 import androidx.appcompat.app.ActionBar;
 import androidx.appcompat.app.AlertDialog;
+import androidx.lifecycle.ViewModelProvider;
 import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView.LayoutManager;
 
@@ -57,11 +55,12 @@ import static org.briarproject.briar.android.controller.SharingController.Sharin
 @MethodsNotNullByDefault
 @ParametersNotNullByDefault
 public class BlogFragment extends BaseFragment
-		implements BlogSharingListener, SharingListener,
+		implements SharingListener, OnBlogPostClickListener {
-		OnBlogPostClickListener {
 
 	private final static String TAG = BlogFragment.class.getName();
 
+	@Inject
+	ViewModelProvider.Factory viewModelFactory;
 	@Inject
 	BlogController blogController;
 	@Inject
@@ -70,11 +69,10 @@ public class BlogFragment extends BaseFragment
 	private Parcelable layoutManagerState;
 
 	private GroupId groupId;
+	private BlogViewModel viewModel;
 	private final BlogPostAdapter adapter = new BlogPostAdapter(this);
 	private LayoutManager layoutManager;
 	private BriarRecyclerView list;
-	private MenuItem writeButton, deleteButton;
-	private boolean isMyBlog = false, canDeleteBlog = false;
 
 	static BlogFragment newInstance(GroupId groupId) {
 		BlogFragment f = new BlogFragment();
@@ -89,7 +87,8 @@ public class BlogFragment extends BaseFragment
 	@Override
 	public void injectFragment(ActivityComponent component) {
 		component.inject(this);
-		blogController.setBlogSharingListener(this);
+		viewModel = new ViewModelProvider(requireActivity(), viewModelFactory)
+				.get(BlogViewModel.class);
 		sharingController.setSharingListener(this);
 	}
 
@@ -112,6 +111,14 @@ public class BlogFragment extends BaseFragment
 		list.showProgressBar();
 		list.setEmptyText(getString(R.string.blogs_other_blog_empty_state));
 
+		viewModel.getBlogPosts().observe(getViewLifecycleOwner(), result ->
+				result.onError(this::handleException)
+						.onSuccess(this::onBlogPostsLoaded)
+		);
+		viewModel.getBlogRemoved().observe(getViewLifecycleOwner(), removed -> {
+			if (removed) finish();
+		});
+
 		if (savedInstanceState != null) {
 			layoutManagerState =
 					savedInstanceState.getParcelable("layoutManager");
@@ -123,16 +130,17 @@ public class BlogFragment extends BaseFragment
 	@Override
 	public void onStart() {
 		super.onStart();
+		viewModel.blockNotifications();
+		viewModel.clearBlogPostNotifications();
 		sharingController.onStart();
-		loadBlog();
 		loadSharedContacts();
-		loadBlogPosts(false);
 		list.startPeriodicUpdate();
 	}
 
 	@Override
 	public void onStop() {
 		super.onStop();
+		viewModel.unblockNotifications();
 		sharingController.onStop();
 		list.stopPeriodicUpdate();
 	}
@@ -140,7 +148,6 @@ public class BlogFragment extends BaseFragment
 	@Override
 	public void onDestroy() {
 		super.onDestroy();
-		blogController.unsetBlogSharingListener(this);
 		sharingController.unsetSharingListener(this);
 	}
 
@@ -156,42 +163,43 @@ public class BlogFragment extends BaseFragment
 	@Override
 	public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
 		inflater.inflate(R.menu.blogs_blog_actions, menu);
-		writeButton = menu.findItem(R.id.action_write_blog_post);
+		MenuItem writeButton = menu.findItem(R.id.action_write_blog_post);
-		if (isMyBlog) writeButton.setVisible(true);
+		MenuItem deleteButton = menu.findItem(R.id.action_blog_delete);
-		deleteButton = menu.findItem(R.id.action_blog_delete);
+		viewModel.getBlog().observe(getViewLifecycleOwner(), blog -> {
-		if (canDeleteBlog) deleteButton.setEnabled(true);
+			setToolbarTitle(blog.getBlog().getAuthor());
-
+			if (blog.isOurs()) writeButton.setVisible(true);
+			if (blog.canBeRemoved()) deleteButton.setEnabled(true);
+		});
 		super.onCreateOptionsMenu(menu, inflater);
 	}
 
 	@Override
 	public boolean onOptionsItemSelected(MenuItem item) {
-		switch (item.getItemId()) {
+		int itemId = item.getItemId();
-			case R.id.action_write_blog_post:
+		if (itemId == R.id.action_write_blog_post) {
-				Intent i = new Intent(getActivity(),
+			Intent i = new Intent(getActivity(),
-						WriteBlogPostActivity.class);
+					WriteBlogPostActivity.class);
-				i.putExtra(GROUP_ID, groupId.getBytes());
+			i.putExtra(GROUP_ID, groupId.getBytes());
-				startActivityForResult(i, REQUEST_WRITE_BLOG_POST);
+			startActivityForResult(i, REQUEST_WRITE_BLOG_POST);
-				return true;
+			return true;
-			case R.id.action_blog_share:
+		} else if (itemId == R.id.action_blog_share) {
-				Intent i2 = new Intent(getActivity(), ShareBlogActivity.class);
+			Intent i2 = new Intent(getActivity(), ShareBlogActivity.class);
-				i2.setFlags(FLAG_ACTIVITY_CLEAR_TOP);
+			i2.setFlags(FLAG_ACTIVITY_CLEAR_TOP);
-				i2.putExtra(GROUP_ID, groupId.getBytes());
+			i2.putExtra(GROUP_ID, groupId.getBytes());
-				startActivityForResult(i2, REQUEST_SHARE_BLOG);
+			startActivityForResult(i2, REQUEST_SHARE_BLOG);
-				return true;
+			return true;
-			case R.id.action_blog_sharing_status:
+		} else if (itemId == R.id.action_blog_sharing_status) {
-				Intent i3 = new Intent(getActivity(),
+			Intent i3 = new Intent(getActivity(),
-						BlogSharingStatusActivity.class);
+					BlogSharingStatusActivity.class);
-				i3.setFlags(FLAG_ACTIVITY_CLEAR_TOP);
+			i3.setFlags(FLAG_ACTIVITY_CLEAR_TOP);
-				i3.putExtra(GROUP_ID, groupId.getBytes());
+			i3.putExtra(GROUP_ID, groupId.getBytes());
-				startActivity(i3);
+			startActivity(i3);
-				return true;
+			return true;
-			case R.id.action_blog_delete:
+		} else if (itemId == R.id.action_blog_delete) {
-				showDeleteDialog();
+			showDeleteDialog();
-				return true;
+			return true;
-			default:
-				return super.onOptionsItemSelected(item);
 		}
+		return super.onOptionsItemSelected(item);
 	}
 
 	@Override
@@ -201,7 +209,7 @@ public class BlogFragment extends BaseFragment
 
 		if (request == REQUEST_WRITE_BLOG_POST && result == RESULT_OK) {
 			displaySnackbar(R.string.blogs_blog_post_created, true);
-			loadBlogPosts(true);
+			viewModel.loadBlogPosts(groupId);
 		} else if (request == REQUEST_SHARE_BLOG && result == RESULT_OK) {
 			displaySnackbar(R.string.blogs_sharing_snackbar, false);
 		}
@@ -212,30 +220,25 @@ public class BlogFragment extends BaseFragment
 		return TAG;
 	}
 
-	@Override
+	private void onBlogPostsLoaded(List<BlogPostItem> items) {
-	public void onBlogPostAdded(BlogPostHeader header, boolean local) {
+		adapter.submitList(items, () -> {
-		blogController.loadBlogPost(header,
+			Boolean wasLocal = viewModel.getPostAddedWasLocalAndReset();
-				new UiResultExceptionHandler<BlogPostItem, DbException>(
+			if (wasLocal != null && wasLocal) {
-						this) {
+				list.scrollToPosition(0);
-					@Override
+				displaySnackbar(R.string.blogs_blog_post_created,
-					public void onResultUi(BlogPostItem post) {
+						false);
-//						adapter.add(post);
+			} else if (wasLocal != null) {
-						if (local) {
+				displaySnackbar(R.string.blogs_blog_post_received,
-							list.scrollToPosition(0);
+						true);
-							displaySnackbar(R.string.blogs_blog_post_created,
+			}
-									false);
+			list.showData();
-						} else {
+			if (layoutManagerState == null) {
-							displaySnackbar(R.string.blogs_blog_post_received,
+				list.scrollToPosition(0);
-									true);
+			} else {
-						}
+				layoutManager.onRestoreInstanceState(
-					}
+						layoutManagerState);
-
+			}
-					@Override
+		});
-					public void onExceptionUi(DbException exception) {
-						handleException(exception);
-					}
-				}
-		);
 	}
 
 	@Override
@@ -262,53 +265,8 @@ public class BlogFragment extends BaseFragment
 		f.show(getParentFragmentManager(), f.getUniqueTag());
 	}
 
-	private void loadBlogPosts(boolean reload) {
-		blogController.loadBlogPosts(
-				new UiResultExceptionHandler<List<BlogPostItem>,
-						DbException>(this) {
-					@Override
-					public void onResultUi(List<BlogPostItem> posts) {
-						if (posts.isEmpty()) {
-							list.showData();
-						} else {
-							adapter.submitList(posts);
-							if (reload || layoutManagerState == null) {
-								list.scrollToPosition(0);
-							} else {
-								layoutManager.onRestoreInstanceState(
-										layoutManagerState);
-							}
-						}
-					}
-
-					@Override
-					public void onExceptionUi(DbException exception) {
-						handleException(exception);
-					}
-				});
-	}
-
-	private void loadBlog() {
-		blogController.loadBlog(
-				new UiResultExceptionHandler<BlogItem, DbException>(this) {
-					@Override
-					public void onResultUi(BlogItem blog) {
-						setToolbarTitle(blog.getBlog().getAuthor());
-						if (blog.isOurs())
-							showWriteButton();
-						if (blog.canBeRemoved())
-							enableDeleteButton();
-					}
-
-					@Override
-					public void onExceptionUi(DbException exception) {
-						handleException(exception);
-					}
-				});
-	}
-
 	private void setToolbarTitle(Author a) {
-		getActivity().setTitle(a.getName());
+		requireActivity().setTitle(a.getName());
 	}
 
 	private void loadSharedContacts() {
@@ -329,20 +287,6 @@ public class BlogFragment extends BaseFragment
 				});
 	}
 
-	@Override
-	public void onBlogInvitationAccepted(ContactId c) {
-		sharingController.add(c);
-		setToolbarSubTitle(sharingController.getTotalCount(),
-				sharingController.getOnlineCount());
-	}
-
-	@Override
-	public void onBlogLeft(ContactId c) {
-		sharingController.remove(c);
-		setToolbarSubTitle(sharingController.getTotalCount(),
-				sharingController.getOnlineCount());
-	}
-
 	@Override
 	public void onSharingInfoUpdated(int total, int online) {
 		setToolbarSubTitle(total, online);
@@ -350,25 +294,13 @@ public class BlogFragment extends BaseFragment
 
 	private void setToolbarSubTitle(int total, int online) {
 		ActionBar actionBar =
-				((BriarActivity) getActivity()).getSupportActionBar();
+				((BriarActivity) requireActivity()).getSupportActionBar();
 		if (actionBar != null) {
 			actionBar.setSubtitle(
 					getString(R.string.shared_with, total, online));
 		}
 	}
 
-	private void showWriteButton() {
-		isMyBlog = true;
-		if (writeButton != null)
-			writeButton.setVisible(true);
-	}
-
-	private void enableDeleteButton() {
-		canDeleteBlog = true;
-		if (deleteButton != null)
-			deleteButton.setEnabled(true);
-	}
-
 	private void displaySnackbar(int stringId, boolean scroll) {
 		BriarSnackbarBuilder sb = new BriarSnackbarBuilder();
 		if (scroll) {
@@ -379,38 +311,21 @@ public class BlogFragment extends BaseFragment
 	}
 
 	private void showDeleteDialog() {
-		DialogInterface.OnClickListener okListener =
+		AlertDialog.Builder builder = new AlertDialog.Builder(requireContext(),
-				(dialog, which) -> deleteBlog();
-		AlertDialog.Builder builder = new AlertDialog.Builder(getActivity(),
 				R.style.BriarDialogTheme);
 		builder.setTitle(getString(R.string.blogs_remove_blog));
 		builder.setMessage(
 				getString(R.string.blogs_remove_blog_dialog_message));
 		builder.setPositiveButton(R.string.cancel, null);
-		builder.setNegativeButton(R.string.blogs_remove_blog_ok, okListener);
+		builder.setNegativeButton(R.string.blogs_remove_blog_ok,
+				(dialog, which) -> deleteBlog());
 		builder.show();
 	}
 
 	private void deleteBlog() {
-		blogController.deleteBlog(
+		viewModel.deleteBlog();
-				new UiResultExceptionHandler<Void, DbException>(this) {
+		Toast.makeText(getActivity(), R.string.blogs_blog_removed, LENGTH_SHORT)
-					@Override
+				.show();
-					public void onResultUi(Void result) {
-						Toast.makeText(getActivity(),
-								R.string.blogs_blog_removed, LENGTH_SHORT)
-								.show();
-						finish();
-					}
-
-					@Override
-					public void onExceptionUi(DbException exception) {
-						handleException(exception);
-					}
-				});
-	}
-
-	@Override
-	public void onBlogRemoved() {
 		finish();
 	}
 

briar-android/src/main/java/org/briarproject/briar/android/blog/BlogModule.java

@@ -21,6 +21,11 @@ public class BlogModule {
 		@IntoMap
 		@ViewModelKey(FeedViewModel.class)
 		abstract ViewModel bindFeedViewModel(FeedViewModel feedViewModel);
+
+		@Binds
+		@IntoMap
+		@ViewModelKey(BlogViewModel.class)
+		abstract ViewModel bindBlogViewModel(BlogViewModel blogViewModel);
 	}
 
 	@ActivityScope

briar-android/src/main/java/org/briarproject/briar/android/blog/BlogPostFragment.java

@@ -1,30 +1,35 @@
 package org.briarproject.briar.android.blog;
 
 import android.os.Bundle;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
 
-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.MessageId;
 import org.briarproject.briar.android.activity.ActivityComponent;
-import org.briarproject.briar.android.blog.BaseController.BlogListener;
-import org.briarproject.briar.android.controller.handler.UiResultExceptionHandler;
-import org.briarproject.briar.api.blog.BlogPostHeader;
 
+import javax.annotation.Nullable;
 import javax.inject.Inject;
 
 import androidx.annotation.UiThread;
+import androidx.lifecycle.ViewModelProvider;
 
 @UiThread
 @MethodsNotNullByDefault
 @ParametersNotNullByDefault
-public class BlogPostFragment extends BasePostFragment implements BlogListener {
+public class BlogPostFragment extends BasePostFragment {
 
 	private static final String TAG = BlogPostFragment.class.getName();
 
+	@Inject
+	ViewModelProvider.Factory viewModelFactory;
 	@Inject
 	BlogController blogController;
 
+	private BlogViewModel viewModel;
+
 	static BlogPostFragment newInstance(MessageId postId) {
 		BlogPostFragment f = new BlogPostFragment();
 
@@ -35,42 +40,29 @@ public class BlogPostFragment extends BasePostFragment implements BlogListener {
 		return f;
 	}
 
+	@Override
+	public void injectFragment(ActivityComponent component) {
+		component.inject(this);
+		viewModel = new ViewModelProvider(requireActivity(), viewModelFactory)
+				.get(BlogViewModel.class);
+	}
+
 	@Override
 	public String getUniqueTag() {
 		return TAG;
 	}
 
+	@Nullable
 	@Override
-	public void injectFragment(ActivityComponent component) {
+	public View onCreateView(LayoutInflater inflater,
-		component.inject(this);
+			@Nullable ViewGroup container,
-	}
+			@Nullable Bundle savedInstanceState) {
-
+		View v = super.onCreateView(inflater, container, savedInstanceState);
-	@Override
+		viewModel.loadBlogPost(postId).observe(getViewLifecycleOwner(), res ->
-	public void onStart() {
+				res.onError(this::handleException)
-		super.onStart();
+						.onSuccess(this::onBlogPostLoaded)
-		blogController.loadBlogPost(postId,
+		);
-				new UiResultExceptionHandler<BlogPostItem, DbException>(
+		return v;
-						this) {
-					@Override
-					public void onResultUi(BlogPostItem post) {
-						onBlogPostLoaded(post);
-					}
-
-					@Override
-					public void onExceptionUi(DbException exception) {
-						handleException(exception);
-					}
-				});
-	}
-
-	@Override
-	public void onBlogPostAdded(BlogPostHeader header, boolean local) {
-		// doesn't matter here
-	}
-
-	@Override
-	public void onBlogRemoved() {
-		finish();
 	}
 
 }

briar-android/src/main/java/org/briarproject/briar/android/blog/BlogViewModel.java

@@ -0,0 +1,168 @@
+package org.briarproject.briar.android.blog;
+
+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.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.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.briar.android.viewmodel.LiveResult;
+import org.briarproject.briar.api.android.AndroidNotificationManager;
+import org.briarproject.briar.api.blog.Blog;
+import org.briarproject.briar.api.blog.BlogInvitationResponse;
+import org.briarproject.briar.api.blog.BlogManager;
+import org.briarproject.briar.api.blog.event.BlogInvitationResponseReceivedEvent;
+import org.briarproject.briar.api.blog.event.BlogPostAddedEvent;
+import org.briarproject.briar.api.sharing.event.ContactLeftShareableEvent;
+
+import java.util.concurrent.Executor;
+import java.util.logging.Logger;
+
+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.util.LogUtils.logDuration;
+import static org.briarproject.bramble.util.LogUtils.logException;
+import static org.briarproject.bramble.util.LogUtils.now;
+
+@NotNullByDefault
+class BlogViewModel extends BaseViewModel {
+
+	private static final Logger LOG = getLogger(BlogViewModel.class.getName());
+
+	// implicitly non-null
+	private volatile GroupId groupId = null;
+
+	private final MutableLiveData<BlogItem> blog = new MutableLiveData<>();
+	private final MutableLiveData<Boolean> blogRemoved =
+			new MutableLiveData<>();
+
+	@Inject
+	BlogViewModel(Application application,
+			@DatabaseExecutor Executor dbExecutor,
+			LifecycleManager lifecycleManager,
+			TransactionManager db,
+			AndroidExecutor androidExecutor,
+			EventBus eventBus,
+			IdentityManager identityManager,
+			AndroidNotificationManager notificationManager,
+			BlogManager blogManager) {
+		super(application, dbExecutor, lifecycleManager, db, androidExecutor,
+				eventBus, identityManager, notificationManager, blogManager);
+	}
+
+	@Override
+	public void eventOccurred(Event e) {
+		if (e instanceof BlogPostAddedEvent) {
+			BlogPostAddedEvent b = (BlogPostAddedEvent) e;
+			if (b.getGroupId().equals(groupId)) {
+				LOG.info("Blog post added");
+				onBlogPostAdded(b.getHeader(), b.isLocal());
+			}
+		} else if (e instanceof BlogInvitationResponseReceivedEvent) {
+			BlogInvitationResponseReceivedEvent b =
+					(BlogInvitationResponseReceivedEvent) e;
+			BlogInvitationResponse r = b.getMessageHeader();
+			if (r.getShareableId().equals(groupId) && r.wasAccepted()) {
+				LOG.info("Blog invitation accepted");
+				// TODO
+//				onBlogInvitationAccepted(b.getContactId());
+// 				sharingController.add(c);
+			}
+		} else if (e instanceof ContactLeftShareableEvent) {
+			ContactLeftShareableEvent s = (ContactLeftShareableEvent) e;
+			if (s.getGroupId().equals(groupId)) {
+				LOG.info("Blog left by contact");
+				// TODO
+//				onBlogLeft(s.getContactId());
+// 				sharingController.remove(c);
+			}
+		} else if (e instanceof GroupRemovedEvent) {
+			GroupRemovedEvent g = (GroupRemovedEvent) e;
+			if (g.getGroup().getId().equals(groupId)) {
+				LOG.info("Blog removed");
+				blogRemoved.setValue(true);
+			}
+		}
+	}
+
+	/**
+	 * Set this before calling any other methods.
+	 */
+	public void setGroupId(GroupId groupId) {
+		this.groupId = groupId;
+		loadBlog(groupId);
+		loadBlogPosts(groupId);
+	}
+
+	private void loadBlog(GroupId groupId) {
+		runOnDbThread(() -> {
+			try {
+				long start = now();
+				LocalAuthor a = identityManager.getLocalAuthor();
+				Blog b = blogManager.getBlog(groupId);
+				boolean ours = a.getId().equals(b.getAuthor().getId());
+				boolean removable = blogManager.canBeRemoved(b);
+				blog.postValue(new BlogItem(b, ours, removable));
+				logDuration(LOG, "Loading blog", start);
+			} catch (DbException e) {
+				logException(LOG, WARNING, e);
+			}
+		});
+	}
+
+	void blockNotifications() {
+		notificationManager.blockNotification(groupId);
+	}
+
+	void clearBlogPostNotifications() {
+		notificationManager.clearBlogPostNotification(groupId);
+	}
+
+	void unblockNotifications() {
+		notificationManager.unblockNotification(groupId);
+	}
+
+	void loadBlogPosts(GroupId groupId) {
+		loadList(txn -> loadBlogPosts(txn, groupId), this::updateBlogPosts);
+	}
+
+	void deleteBlog() {
+		runOnDbThread(() -> {
+			try {
+				long start = now();
+				Blog b = blogManager.getBlog(groupId);
+				blogManager.removeBlog(b);
+				logDuration(LOG, "Removing blog", start);
+			} catch (DbException e) {
+				logException(LOG, WARNING, e);
+			}
+		});
+	}
+
+	LiveData<LiveResult<BlogPostItem>> loadBlogPost(MessageId m) {
+		return loadBlogPost(groupId, m);
+	}
+
+	LiveData<BlogItem> getBlog() {
+		return blog;
+	}
+
+	LiveData<Boolean> getBlogRemoved() {
+		return blogRemoved;
+	}
+
+}

briar-android/src/main/java/org/briarproject/briar/android/blog/FeedFragment.java

@@ -63,8 +63,7 @@ public class FeedFragment extends BaseFragment
 	@Override
 	public void injectFragment(ActivityComponent component) {
 		component.inject(this);
-		// TODO don't use NavDrawerActivity scope here
+		viewModel = new ViewModelProvider(this, viewModelFactory)
-		viewModel = new ViewModelProvider(requireActivity(), viewModelFactory)
 				.get(FeedViewModel.class);
 		// TODO ideally we only do this once when the ViewModel gets created
 		viewModel.loadPersonalBlog();
@@ -88,7 +87,7 @@ public class FeedFragment extends BaseFragment
 		list.setEmptyText(R.string.blogs_feed_empty_state);
 		list.setEmptyAction(R.string.blogs_feed_empty_state_action);
 
-		viewModel.getAllBlogPosts().observe(getViewLifecycleOwner(), result ->
+		viewModel.getBlogPosts().observe(getViewLifecycleOwner(), result ->
 				result
 						.onError(this::handleException)
 						.onSuccess(this::onBlogPostsLoaded)
@@ -135,6 +134,7 @@ public class FeedFragment extends BaseFragment
 			} else if (wasLocal != null) {
 				showSnackBar(R.string.blogs_blog_post_received);
 			}
+			list.showData();
 		});
 	}
 

briar-android/src/main/java/org/briarproject/briar/android/blog/FeedViewModel.java

@@ -17,11 +17,9 @@ import org.briarproject.bramble.api.sync.GroupId;
 import org.briarproject.bramble.api.sync.event.GroupAddedEvent;
 import org.briarproject.bramble.api.sync.event.GroupRemovedEvent;
 import org.briarproject.bramble.api.system.AndroidExecutor;
-import org.briarproject.briar.android.viewmodel.LiveResult;
 import org.briarproject.briar.api.android.AndroidNotificationManager;
 import org.briarproject.briar.api.blog.Blog;
 import org.briarproject.briar.api.blog.BlogManager;
-import org.briarproject.briar.api.blog.BlogPostHeader;
 import org.briarproject.briar.api.blog.event.BlogPostAddedEvent;
 
 import java.util.ArrayList;
@@ -30,10 +28,8 @@ import java.util.List;
 import java.util.concurrent.Executor;
 import java.util.logging.Logger;
 
-import javax.annotation.Nullable;
 import javax.inject.Inject;
 
-import androidx.annotation.UiThread;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.MutableLiveData;
 
@@ -49,11 +45,7 @@ class FeedViewModel extends BaseViewModel {
 
 	private static final Logger LOG = getLogger(FeedViewModel.class.getName());
 
-	protected final AndroidNotificationManager notificationManager;
-
 	private final MutableLiveData<Blog> personalBlog = new MutableLiveData<>();
-	@Nullable
-	private Boolean postAddedWasLocal = null;
 
 	@Inject
 	FeedViewModel(Application application,
@@ -63,11 +55,10 @@ class FeedViewModel extends BaseViewModel {
 			AndroidExecutor androidExecutor,
 			EventBus eventBus,
 			IdentityManager identityManager,
-			BlogManager blogManager,
+			AndroidNotificationManager notificationManager,
-			AndroidNotificationManager notificationManager) {
+			BlogManager blogManager) {
 		super(application, dbExecutor, lifecycleManager, db, androidExecutor,
-				eventBus, identityManager, blogManager);
+				eventBus, identityManager, notificationManager, blogManager);
-		this.notificationManager = notificationManager;
 	}
 
 	@Override
@@ -122,7 +113,7 @@ class FeedViewModel extends BaseViewModel {
 	}
 
 	void loadAllBlogPosts() {
-		loadList(this::loadAllBlogPosts, blogPosts::setValue);
+		loadList(this::loadAllBlogPosts, this::updateBlogPosts);
 	}
 
 	@DatabaseExecutor
@@ -142,33 +133,4 @@ class FeedViewModel extends BaseViewModel {
 		return posts;
 	}
 
-	private void onBlogPostAdded(BlogPostHeader header, boolean local) {
-		postAddedWasLocal = local;
-		runOnDbThread(() -> {
-			try {
-				db.transaction(true, txn -> {
-					BlogPostItem item = getItem(txn, header);
-					txn.attach(() -> {
-						List<BlogPostItem> items = addListItem(blogPosts, item);
-						if (items != null) {
-							Collections.sort(items);
-							blogPosts.setValue(new LiveResult<>(items));
-						}
-					});
-				});
-			} catch (DbException e) {
-				logException(LOG, WARNING, e);
-			}
-		});
-	}
-
-	@UiThread
-	@Nullable
-	Boolean getPostAddedWasLocalAndReset() {
-		if (postAddedWasLocal == null) return null;
-		boolean wasLocal = postAddedWasLocal;
-		postAddedWasLocal = null;
-		return wasLocal;
-	}
-
 }