Merge branch 'live-event' into 'master'

Migrate existing uses of event-like LiveData to LiveEvent

See merge request briar/briar!1090

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

@@ -363,7 +363,7 @@ public class ConversationActivity extends BriarActivity
 			if (enable != null && enable) {
 				menu.findItem(R.id.action_introduction).setEnabled(true);
 				// show introduction onboarding, if needed
-				observeOnce(viewModel.showIntroductionOnboarding(), this,
+				viewModel.showIntroductionOnboarding().observeEvent(this,
 						this::showIntroductionOnboarding);
 			}
 		});
@@ -474,9 +474,8 @@ public class ConversationActivity extends BriarActivity
 			if (revision == adapter.getRevision()) {
 				adapter.incrementRevision();
 				textInputView.setReady(true);
-				// start observing onboarding after enabling (only once, because
+				// start observing onboarding after enabling
-				// we only update this when an onboarding should be shown)
+				viewModel.showImageOnboarding().observeEvent(this,
-				observeOnce(viewModel.showImageOnboarding(), this,
 						this::showImageOnboarding);
 				List<ConversationItem> items = createItems(headers);
 				adapter.addAll(items);
@@ -499,7 +498,6 @@ public class ConversationActivity extends BriarActivity
 	 * <p>
 	 * Attention: Call this only after contactName has been initialized.
 	 */
-	@SuppressWarnings("ConstantConditions")
 	private List<ConversationItem> createItems(
 			Collection<ConversationMessageHeader> headers) {
 		List<ConversationItem> items = new ArrayList<>(headers.size());
@@ -715,8 +713,8 @@ public class ConversationActivity extends BriarActivity
 		});
 	}
 
-	private void showImageOnboarding(@Nullable Boolean show) {
+	private void showImageOnboarding(Boolean show) {
-		if (show == null || !show) return;
+		if (!show) return;
 		if (SDK_INT >= 21) {
 			// show onboarding only after the enter transition has ended
 			// otherwise the tap target animation won't play

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

@@ -28,6 +28,8 @@ import org.briarproject.bramble.api.sync.GroupId;
 import org.briarproject.bramble.api.sync.Message;
 import org.briarproject.bramble.api.sync.MessageId;
 import org.briarproject.briar.android.util.UiUtils;
+import org.briarproject.briar.android.viewmodel.LiveEvent;
+import org.briarproject.briar.android.viewmodel.MutableLiveEvent;
 import org.briarproject.briar.api.messaging.Attachment;
 import org.briarproject.briar.api.messaging.AttachmentHeader;
 import org.briarproject.briar.api.messaging.MessagingManager;
@@ -87,10 +89,10 @@ public class ConversationViewModel extends AndroidViewModel {
 			Transformations.map(contact, UiUtils::getContactDisplayName);
 	private final MutableLiveData<Boolean> imageSupport =
 			new MutableLiveData<>();
-	private final MutableLiveData<Boolean> showImageOnboarding =
+	private final MutableLiveEvent<Boolean> showImageOnboarding =
-			new MutableLiveData<>();
+			new MutableLiveEvent<>();
-	private final MutableLiveData<Boolean> showIntroductionOnboarding =
+	private final MutableLiveEvent<Boolean> showIntroductionOnboarding =
-			new MutableLiveData<>();
+			new MutableLiveEvent<>();
 	private final MutableLiveData<Boolean> showIntroductionAction =
 			new MutableLiveData<>();
 	private final MutableLiveData<Boolean> contactDeleted =
@@ -212,32 +214,30 @@ public class ConversationViewModel extends AndroidViewModel {
 		if (imagesSupported &&
 				settings.getBoolean(SHOW_ONBOARDING_IMAGE, true)) {
 			// check if we should show onboarding, only if images are supported
-			showImageOnboarding.postValue(true);
+			showImageOnboarding.postEvent(true);
 			// allow observer to stop listening for changes
-			showIntroductionOnboarding.postValue(false);
+			showIntroductionOnboarding.postEvent(false);
 		} else {
 			// allow observer to stop listening for changes
-			showImageOnboarding.postValue(false);
+			showImageOnboarding.postEvent(false);
 			// we only show one onboarding dialog at a time
 			if (introductionSupported &&
 					settings.getBoolean(SHOW_ONBOARDING_INTRODUCTION, true)) {
-				showIntroductionOnboarding.postValue(true);
+				showIntroductionOnboarding.postEvent(true);
 			} else {
 				// allow observer to stop listening for changes
-				showIntroductionOnboarding.postValue(false);
+				showIntroductionOnboarding.postEvent(false);
 			}
 		}
 	}
 
 	@UiThread
 	void onImageOnboardingSeen() {
-		showImageOnboarding.setValue(false);
 		onOnboardingSeen(SHOW_ONBOARDING_IMAGE);
 	}
 
 	@UiThread
 	void onIntroductionOnboardingSeen() {
-		showIntroductionOnboarding.setValue(false);
 		onOnboardingSeen(SHOW_ONBOARDING_INTRODUCTION);
 	}
 
@@ -365,11 +365,11 @@ public class ConversationViewModel extends AndroidViewModel {
 		return imageSupport;
 	}
 
-	LiveData<Boolean> showImageOnboarding() {
+	LiveEvent<Boolean> showImageOnboarding() {
 		return showImageOnboarding;
 	}
 
-	LiveData<Boolean> showIntroductionOnboarding() {
+	LiveEvent<Boolean> showIntroductionOnboarding() {
 		return showIntroductionOnboarding;
 	}
 

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

@@ -100,7 +100,8 @@ public class ImageActivity extends BriarActivity
 		// get View Model
 		viewModel = ViewModelProviders.of(this, viewModelFactory)
 				.get(ImageViewModel.class);
-		viewModel.getSaveState().observe(this, this::onImageSaveStateChanged);
+		viewModel.getSaveState().observeEvent(this,
+				this::onImageSaveStateChanged);
 
 		// inflate layout
 		setContentView(R.layout.activity_image);
@@ -141,7 +142,8 @@ public class ImageActivity extends BriarActivity
 		viewPager.setCurrentItem(position);
 
 		if (SDK_INT >= 16) {
-			viewModel.getOnImageClicked().observe(this, this::onImageClicked);
+			viewModel.getOnImageClicked()
+					.observeEvent(this, this::onImageClicked);
 			window.getDecorView().setSystemUiVisibility(UI_FLAGS_DEFAULT);
 		}
 	}
@@ -222,7 +224,6 @@ public class ImageActivity extends BriarActivity
 	private void onImageClicked(@Nullable Boolean clicked) {
 		if (clicked != null && clicked) {
 			toggleSystemUi();
-			viewModel.onOnImageClickSeen();
 		}
 	}
 
@@ -312,7 +313,6 @@ public class ImageActivity extends BriarActivity
 				.setBackgroundColor(colorRes)
 				.make(layout, stringRes, LENGTH_LONG)
 				.show();
-		viewModel.onSaveStateSeen();
 	}
 
 	AttachmentItem getVisibleAttachment() {

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

@@ -2,8 +2,6 @@ package org.briarproject.briar.android.conversation;
 
 import android.app.Application;
 import android.arch.lifecycle.AndroidViewModel;
-import android.arch.lifecycle.LiveData;
-import android.arch.lifecycle.MutableLiveData;
 import android.graphics.drawable.Drawable;
 import android.net.Uri;
 import android.support.annotation.Nullable;
@@ -15,6 +13,8 @@ import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.sync.MessageId;
+import org.briarproject.briar.android.viewmodel.LiveEvent;
+import org.briarproject.briar.android.viewmodel.MutableLiveEvent;
 import org.briarproject.briar.api.messaging.Attachment;
 import org.briarproject.briar.api.messaging.MessagingManager;
 
@@ -53,9 +53,10 @@ public class ImageViewModel extends AndroidViewModel {
 	/**
 	 * true means there was an error saving the image, false if image was saved.
 	 */
-	private final MutableLiveData<Boolean> saveState = new MutableLiveData<>();
+	private final MutableLiveEvent<Boolean> saveState =
-	private final MutableLiveData<Boolean> imageClicked =
+			new MutableLiveEvent<>();
-			new MutableLiveData<>();
+	private final MutableLiveEvent<Boolean> imageClicked =
+			new MutableLiveEvent<>();
 	private int toolbarTop, toolbarBottom;
 
 	@Inject
@@ -70,24 +71,17 @@ public class ImageViewModel extends AndroidViewModel {
 	}
 
 	void clickImage() {
-		imageClicked.setValue(true);
+		imageClicked.setEvent(true);
 	}
 
 	/**
-	 * A LiveData that is true if the image was clicked,
+	 * A LiveEvent that is true if the image was clicked,
 	 * false if it wasn't.
-	 *
-	 * Call {@link #onOnImageClickSeen()} after consuming an update.
 	 */
-	LiveData<Boolean> getOnImageClicked() {
+	LiveEvent<Boolean> getOnImageClicked() {
 		return imageClicked;
 	}
 
-	@UiThread
-	void onOnImageClickSeen() {
-		imageClicked.setValue(false);
-	}
-
 	void setToolbarPosition(int top, int bottom) {
 		toolbarTop = top;
 		toolbarBottom = bottom;
@@ -111,26 +105,18 @@ public class ImageViewModel extends AndroidViewModel {
 	/**
 	 * A LiveData that is true if there was an error
 	 * and false if the image was saved.
-	 * It can be null otherwise, if no image was saved recently.
-	 *
-	 * Call {@link #onSaveStateSeen()} after consuming an update.
 	 */
-	LiveData<Boolean> getSaveState() {
+	LiveEvent<Boolean> getSaveState() {
 		return saveState;
 	}
 
-	@UiThread
-	void onSaveStateSeen() {
-		saveState.setValue(null);
-	}
-
 	/**
 	 * Saves the attachment to a writeable {@link Uri}.
 	 */
 	@UiThread
 	void saveImage(AttachmentItem attachment, @Nullable Uri uri) {
 		if (uri == null) {
-			saveState.setValue(true);
+			saveState.setEvent(true);
 		} else {
 			saveImage(attachment, () -> getOutputStream(uri), null);
 		}
@@ -155,7 +141,7 @@ public class ImageViewModel extends AndroidViewModel {
 				copyImageFromDb(a, osp, afterCopy);
 			} catch (DbException e) {
 				logException(LOG, WARNING, e);
-				saveState.postValue(true);
+				saveState.postEvent(true);
 			}
 		});
 	}
@@ -168,10 +154,10 @@ public class ImageViewModel extends AndroidViewModel {
 				OutputStream os = osp.getOutputStream();
 				copyAndClose(is, os);
 				if (afterCopy != null) afterCopy.run();
-				saveState.postValue(false);
+				saveState.postEvent(false);
 			} catch (IOException e) {
 				logException(LOG, WARNING, e);
-				saveState.postValue(true);
+				saveState.postEvent(true);
 			}
 		});
 	}