Specify whether dismissing an item requires a list rebuild or not.

The controller in charge of dismissing an item will have an insight into
whether it will cause a re-query for an existing cursor or not. If a re-query
will occur in response to a `ContentResolver#notifyChange()` invokation (in this
case in response to updating `AppPrefs`), then the `UpdatesAdapter` doesn't
need to rebuild itself yet. If it is a status update, then it should update
the adapter right away.

Seeing as the controller was already returning one thing (a message to be
displayed in a `Toast` and now it also needs to return an opinion on whether
to rebuild the adapter or not, this has been extracted into a value object
which has a message and a rebuild adapter flag.

app/src/main/java/org/fdroid/fdroid/views/apps/AppListItemController.java

@@ -26,7 +26,6 @@ import android.widget.ImageButton;
 import android.widget.ImageView;
 import android.widget.ProgressBar;
 import android.widget.TextView;
-import android.widget.Toast;
 
 import com.nostra13.universalimageloader.core.DisplayImageOptions;
 import com.nostra13.universalimageloader.core.ImageLoader;
@@ -43,6 +42,7 @@ import org.fdroid.fdroid.installer.ApkCache;
 import org.fdroid.fdroid.installer.InstallManagerService;
 import org.fdroid.fdroid.installer.Installer;
 import org.fdroid.fdroid.installer.InstallerFactory;
+import org.fdroid.fdroid.views.updates.DismissResult;
 
 import java.io.File;
 import java.util.Iterator;
@@ -203,13 +203,13 @@ public abstract class AppListItemController extends RecyclerView.ViewHolder {
      * This mainly exists to keep the API consistent, in that the {@link App} is threaded through to the relevant
      * method with a guarantee that it is not null, rather than every method having to check if it is null or not.
      */
-    public final void onDismiss() {
+    @NonNull
+    public final DismissResult onDismiss() {
         if (currentApp != null && canDismiss()) {
-            CharSequence message = onDismissApp(currentApp);
+            return onDismissApp(currentApp);
-            if (message != null) {
-                Toast.makeText(activity, message, Toast.LENGTH_SHORT).show();
-            }
         }
+
+        return new DismissResult();
     }
 
     /**
@@ -218,9 +218,9 @@ public abstract class AppListItemController extends RecyclerView.ViewHolder {
      * a {@link android.widget.Toast} for a {@link android.widget.Toast#LENGTH_SHORT} time.
      * @see #canDismiss() This must also be overriden and should return true.
      */
-    @Nullable
+    @NonNull
-    protected CharSequence onDismissApp(@NonNull App app) {
+    protected DismissResult onDismissApp(@NonNull App app) {
-        return null;
+        return new DismissResult();
     }
 
     /**

app/src/main/java/org/fdroid/fdroid/views/main/MainActivity.java

@@ -379,7 +379,7 @@ public class MainActivity extends AppCompatActivity implements BottomNavigationB
             AppUpdateStatusManager manager = AppUpdateStatusManager.getInstance(context);
 
             String reason = intent.getStringExtra(AppUpdateStatusManager.EXTRA_REASON_FOR_CHANGE);
-            switch(intent.getAction()) {
+            switch (intent.getAction()) {
                 // Apps which are added/removed from the list due to becoming ready to install or a repo being
                 // disabled both cause us to increase/decrease our badge count respectively.
                 case AppUpdateStatusManager.BROADCAST_APPSTATUS_LIST_CHANGED:

app/src/main/java/org/fdroid/fdroid/views/updates/DismissResult.java

@@ -0,0 +1,29 @@
+package org.fdroid.fdroid.views.updates;
+
+import android.support.annotation.Nullable;
+
+/**
+ * When dismissing an item from the Updates tab, there is two different things we need to return.
+ * This is a dumb data object to represent these things, because a method is only allowed to return one thing.
+ */
+public class DismissResult {
+
+    @Nullable
+    public final CharSequence message;
+
+    public final boolean requiresAdapterRefresh;
+
+    public DismissResult() {
+        this(null, false);
+    }
+
+    public DismissResult(boolean requiresAdapterRefresh) {
+        this(null, requiresAdapterRefresh);
+    }
+
+    public DismissResult(@Nullable CharSequence message, boolean requiresAdapterRefresh) {
+        this.message = message;
+        this.requiresAdapterRefresh = requiresAdapterRefresh;
+    }
+
+}

app/src/main/java/org/fdroid/fdroid/views/updates/UpdatesAdapter.java

@@ -343,14 +343,9 @@ public class UpdatesAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder
 
     /**
      * If an item representing an {@link org.fdroid.fdroid.AppUpdateStatusManager.AppUpdateStatus} is dismissed,
-     * then we should rebuild the list of app statuses and update the adapter. If it was an updateable app which was
+     * then we should rebuild the list of app statuses and update the adapter.
-     * dismissed, then it is still harmless to rebuild the list of items anyway, but this isn't strictly required
-     * because the act of marking an app as "Ignored" will trigger the {@link AppProvider} to re-query for a list
-     * of updateable apps, separate to this method. However, by the time we get here it is a bit tricky to figure
-     * out which item was dismissed, so for simplicity (and to make the behaviour more deterministic) we always
-     * rebuild the full updates list.
      */
-    public void onItemDismissed() {
+    public void refreshStatuses() {
         onAppStatusRemoved();
     }
 }

app/src/main/java/org/fdroid/fdroid/views/updates/UpdatesItemTouchCallback.java

@@ -1,7 +1,9 @@
 package org.fdroid.fdroid.views.updates;
 
+import android.content.Context;
 import android.support.v7.widget.RecyclerView;
 import android.support.v7.widget.helper.ItemTouchHelper;
+import android.widget.Toast;
 
 import org.fdroid.fdroid.views.apps.AppListItemController;
 import org.fdroid.fdroid.views.updates.items.AppStatusListItemController;
@@ -31,9 +33,11 @@ import org.fdroid.fdroid.views.updates.items.UpdateableAppListItemController;
  */
 public class UpdatesItemTouchCallback extends ItemTouchHelper.Callback {
 
+    private final Context context;
     private final UpdatesAdapter adapter;
 
-    public UpdatesItemTouchCallback(UpdatesAdapter adapter) {
+    public UpdatesItemTouchCallback(Context context, UpdatesAdapter adapter) {
+        this.context = context;
         this.adapter = adapter;
     }
 
@@ -58,8 +62,15 @@ public class UpdatesItemTouchCallback extends ItemTouchHelper.Callback {
     @Override
     public void onSwiped(RecyclerView.ViewHolder viewHolder, int direction) {
         AppListItemController controller = (AppListItemController) viewHolder;
-        controller.onDismiss();
+        DismissResult result = controller.onDismiss();
-        adapter.onItemDismissed();
+
+        if (result.message != null) {
+            Toast.makeText(context, result.message, Toast.LENGTH_SHORT).show();
+        }
+
+        if (result.requiresAdapterRefresh) {
+            adapter.refreshStatuses();
+        }
     }
 
     @Override

app/src/main/java/org/fdroid/fdroid/views/updates/UpdatesViewBinder.java

@@ -29,7 +29,7 @@ public class UpdatesViewBinder {
         list.setLayoutManager(new LinearLayoutManager(activity));
         list.setAdapter(adapter);
 
-        ItemTouchHelper touchHelper = new ItemTouchHelper(new UpdatesItemTouchCallback(adapter));
+        ItemTouchHelper touchHelper = new ItemTouchHelper(new UpdatesItemTouchCallback(activity, adapter));
         touchHelper.attachToRecyclerView(list);
 
         emptyState = (TextView) view.findViewById(R.id.empty_state);

app/src/main/java/org/fdroid/fdroid/views/updates/items/AppStatusListItemController.java

@@ -11,6 +11,7 @@ import org.fdroid.fdroid.R;
 import org.fdroid.fdroid.data.App;
 import org.fdroid.fdroid.views.apps.AppListItemController;
 import org.fdroid.fdroid.views.apps.AppListItemState;
+import org.fdroid.fdroid.views.updates.DismissResult;
 
 /**
  * Shows apps which are:
@@ -51,9 +52,9 @@ public class AppStatusListItemController extends AppListItemController {
         return true;
     }
 
-    @Nullable
+    @NonNull
     @Override
-    protected CharSequence onDismissApp(@NonNull App app) {
+    protected DismissResult onDismissApp(@NonNull App app) {
         AppUpdateStatus status = getCurrentStatus();
         if (status != null) {
             AppUpdateStatusManager manager = AppUpdateStatusManager.getInstance(activity);
@@ -69,6 +70,6 @@ public class AppStatusListItemController extends AppListItemController {
             }
         }
 
-        return null;
+        return new DismissResult(true);
     }
 }

app/src/main/java/org/fdroid/fdroid/views/updates/items/KnownVulnAppListItemController.java

@@ -24,6 +24,7 @@ import org.fdroid.fdroid.installer.Installer;
 import org.fdroid.fdroid.installer.InstallerService;
 import org.fdroid.fdroid.views.apps.AppListItemController;
 import org.fdroid.fdroid.views.apps.AppListItemState;
+import org.fdroid.fdroid.views.updates.DismissResult;
 
 /**
  * Tell the user that an app they have installed has a known vulnerability.
@@ -88,9 +89,9 @@ public class KnownVulnAppListItemController extends AppListItemController {
     }
 
     @Override
-    protected CharSequence onDismissApp(@NonNull App app) {
+    protected DismissResult onDismissApp(@NonNull App app) {
         this.ignoreVulnerableApp(app);
-        return activity.getString(R.string.app_list__dismiss_vulnerable_app);
+        return new DismissResult(activity.getString(R.string.app_list__dismiss_vulnerable_app), false);
     }
 
     @Override

app/src/main/java/org/fdroid/fdroid/views/updates/items/UpdateableAppListItemController.java

@@ -12,6 +12,7 @@ import org.fdroid.fdroid.data.AppPrefs;
 import org.fdroid.fdroid.data.AppPrefsProvider;
 import org.fdroid.fdroid.views.apps.AppListItemController;
 import org.fdroid.fdroid.views.apps.AppListItemState;
+import org.fdroid.fdroid.views.updates.DismissResult;
 
 /**
  * Very trimmed down list item. Only displays the app icon, name, and a download button.
@@ -38,14 +39,14 @@ public class UpdateableAppListItemController extends AppListItemController {
     }
 
     @Override
-    @Nullable
+    @NonNull
-    protected CharSequence onDismissApp(@NonNull App app) {
+    protected DismissResult onDismissApp(@NonNull App app) {
         AppPrefs prefs = app.getPrefs(activity);
         prefs.ignoreThisUpdate = app.suggestedVersionCode;
 
         // The act of updating here will trigger a re-query of the "can update" apps, so no need to do anything else
         // to update the UI in response to this.
         AppPrefsProvider.Helper.update(activity, app, prefs);
-        return activity.getString(R.string.app_list__dismiss_app_update);
+        return new DismissResult(activity.getString(R.string.app_list__dismiss_app_update), false);
     }
 }