Experiment: quick switch unified folders

app/src/main/java/eu/faircode/email/DaoFolder.java

@@ -100,7 +100,7 @@ public interface DaoFolder {
             " GROUP BY folder.id")
     LiveData<List<TupleFolderEx>> liveFolders(Long account, boolean primary);
 
-    @Query("SELECT folder.*" +
+    final String queryUnified = "SELECT folder.*" +
             ", account.id AS accountId, account.pop AS accountProtocol, account.`order` AS accountOrder" +
             ", account.name AS accountName, account.category AS accountCategory, account.color AS accountColor" +
             ", account.state AS accountState, account.error AS accountError" +
@@ -117,9 +117,14 @@ public interface DaoFolder {
             " LEFT JOIN operation ON operation.folder = folder.id" +
             " WHERE account.`synchronize`" +
             " AND ((:type IS NULL AND folder.unified) OR folder.type = :type)" +
-            " GROUP BY folder.id")
+            " GROUP BY folder.id";
+
+    @Query(queryUnified)
     LiveData<List<TupleFolderEx>> liveUnified(String type);
 
+    @Query(queryUnified)
+    List<TupleFolderEx> getUnified(String type);
+
     @Query("SELECT folder.account, folder.id AS folder, unified, sync_state" +
             " FROM folder" +
             " JOIN account ON account.id = folder.account" +

app/src/main/java/eu/faircode/email/FragmentBase.java

@@ -62,6 +62,7 @@ import androidx.fragment.app.FragmentActivity;
 import androidx.fragment.app.FragmentResultListener;
 import androidx.lifecycle.Lifecycle;
 import androidx.lifecycle.LifecycleObserver;
+import androidx.lifecycle.LifecycleOwner;
 import androidx.lifecycle.OnLifecycleEvent;
 import androidx.preference.PreferenceManager;
 
@@ -137,6 +138,33 @@ public class FragmentBase extends Fragment {
         updateSubtitle();
     }
 
+    protected void setActionBarListener(final LifecycleOwner owner, final View.OnClickListener listener) {
+        final AppCompatActivity activity = (AppCompatActivity) getActivity();
+        if (activity == null)
+            return;
+
+        final ActionBar actionbar = activity.getSupportActionBar();
+        if (actionbar == null)
+            return;
+
+        if ((actionbar.getDisplayOptions() & DISPLAY_SHOW_CUSTOM) == 0)
+            return;
+
+        final View custom = actionbar.getCustomView();
+        if (custom == null)
+            return;
+
+        owner.getLifecycle().addObserver(new LifecycleObserver() {
+            @OnLifecycleEvent(Lifecycle.Event.ON_ANY)
+            public void onAny() {
+                Lifecycle.State state = owner.getLifecycle().getCurrentState();
+                custom.setOnClickListener(state.isAtLeast(Lifecycle.State.STARTED) ? listener : null);
+                if (Lifecycle.State.DESTROYED.equals(state))
+                    owner.getLifecycle().removeObserver(this);
+            }
+        });
+    }
+
     @Override
     public void onCreateOptionsMenu(@NonNull Menu menu, @NonNull MenuInflater inflater) {
         super.onCreateOptionsMenu(menu, inflater);

app/src/main/java/eu/faircode/email/FragmentMessages.java

@@ -555,6 +555,59 @@ public class FragmentMessages extends FragmentBase
     public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
         setHasOptionsMenu(true);
 
+        setActionBarListener(getViewLifecycleOwner(), new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                new SimpleTask<List<TupleFolderEx>>() {
+                    @Override
+                    protected List<TupleFolderEx> onExecute(Context context, Bundle args) {
+                        DB db = DB.getInstance(context);
+                        return db.folder().getUnified(null);
+                    }
+
+                    @Override
+                    protected void onExecuted(Bundle args, final List<TupleFolderEx> folders) {
+                        if (folders == null)
+                            return;
+
+                        final Context context = getContext();
+                        if (context == null)
+                            return;
+
+                        Collections.sort(folders, folders.get(0).getComparator(context));
+
+                        List<CharSequence> items = new ArrayList<>();
+                        for (TupleFolderEx folder : folders)
+                            items.add(folder.accountName + "/" + folder.getDisplayName(context));
+
+                        new AlertDialog.Builder(context)
+                                .setIcon(R.drawable.twotone_folder_open_24)
+                                .setTitle(R.string.title_folders_unified)
+                                .setItems(items.toArray(new CharSequence[0]), new DialogInterface.OnClickListener() {
+                                    @Override
+                                    public void onClick(DialogInterface dialog, int which) {
+                                        TupleFolderEx folder = folders.get(which);
+
+                                        LocalBroadcastManager lbm = LocalBroadcastManager.getInstance(context);
+                                        lbm.sendBroadcast(
+                                                new Intent(ActivityView.ACTION_VIEW_MESSAGES)
+                                                        .putExtra("account", folder.account)
+                                                        .putExtra("folder", folder.id)
+                                                        .putExtra("type", folder.type));
+                                    }
+                                })
+                                .setPositiveButton(android.R.string.cancel, null)
+                                .show();
+                    }
+
+                    @Override
+                    protected void onException(Bundle args, Throwable ex) {
+                        Log.unexpectedError(getParentFragment(), ex);
+                    }
+                }.execute(FragmentMessages.this, new Bundle(), "unified");
+            }
+        });
+
         view = (ViewGroup) inflater.inflate(R.layout.fragment_messages, container, false);
 
         // Get controls