Finish existing secondary containers when starting to side

When a new activity is started to side of a primary container in an
existing split, finish the old secondary container by default to
replace it instead of putting on top.

Note that this rule only applies for new activity launches to side
via rules or dedicated APIs. If an activity is started regularly,
it would normally be placed in the existing secondary container on
top, not creating a new one and replacing.

Bug: 194996352
Test: Start to side from the primary container several times,
observe secondary container being replaced with subsequent launches.

Change-Id: If4439368a669c6252c97471f0e77286357285c9d

libs/WindowManager/Jetpack/src/androidx/window/extensions/organizer/JetpackTaskFragmentOrganizer.java

@@ -96,11 +96,11 @@ class JetpackTaskFragmentOrganizer extends TaskFragmentOrganizer {
      * @param activityIntent    Intent to start the secondary Activity with.
      * @param activityOptions   ActivityOptions to start the secondary Activity with.
      */
-    void startActivityToSide(IBinder launchingFragmentToken, Rect launchingFragmentBounds,
-            Activity launchingActivity, IBinder secondaryFragmentToken,
-            Rect secondaryFragmentBounds,  Intent activityIntent,
+    void startActivityToSide(@NonNull WindowContainerTransaction wct,
+            @NonNull IBinder launchingFragmentToken, @NonNull Rect launchingFragmentBounds,
+            @NonNull Activity launchingActivity, @NonNull IBinder secondaryFragmentToken,
+            @NonNull Rect secondaryFragmentBounds, @NonNull Intent activityIntent,
             @Nullable Bundle activityOptions) {
-        final WindowContainerTransaction wct = new WindowContainerTransaction();
         final IBinder ownerToken = launchingActivity.getActivityToken();
 
         // Create or resize the launching TaskFragment.
@@ -118,8 +118,6 @@ class JetpackTaskFragmentOrganizer extends TaskFragmentOrganizer {
 
         // Set adjacent to each other so that the containers below will be invisible.
         wct.setAdjacentTaskFragments(launchingFragmentToken, secondaryFragmentToken);
-
-        applyTransaction(wct);
     }
 
     /**

libs/WindowManager/Jetpack/src/androidx/window/extensions/organizer/SplitController.java

@@ -296,12 +296,15 @@ public class SplitController implements JetpackTaskFragmentOrganizer.TaskFragmen
     }
 
     /**
-     * Creates and registers a new split with the provided containers and configuration.
+     * Creates and registers a new split with the provided containers and configuration. Finishes
+     * existing secondary containers if found for the given primary container.
      */
-    void registerSplit(@NonNull TaskFragmentContainer primaryContainer,
-            @NonNull Activity primaryActivity,
+    void registerSplit(@NonNull WindowContainerTransaction wct,
+            @NonNull TaskFragmentContainer primaryContainer, @NonNull Activity primaryActivity,
             @NonNull TaskFragmentContainer secondaryContainer,
             @NonNull ExtensionSplitPairRule splitPairRule) {
+        removeExistingSecondaryContainers(wct, primaryContainer);
+
         SplitContainer splitContainer = new SplitContainer(primaryContainer, primaryActivity,
                 secondaryContainer, splitPairRule);
         mSplitContainers.add(splitContainer);
@@ -323,6 +326,25 @@ public class SplitController implements JetpackTaskFragmentOrganizer.TaskFragmen
         mSplitContainers.removeAll(containersToRemove);
     }
 
+    /**
+     * Removes a secondary container for the given primary container if an existing split is
+     * already registered.
+     */
+    void removeExistingSecondaryContainers(@NonNull WindowContainerTransaction wct,
+            @NonNull TaskFragmentContainer primaryContainer) {
+        // If the primary container was already in a split - remove the secondary container that
+        // is now covered by the new one that replaced it.
+        final SplitContainer existingSplitContainer = getActiveSplitForContainer(
+                primaryContainer);
+        if (existingSplitContainer == null
+                || primaryContainer == existingSplitContainer.getSecondaryContainer()) {
+            return;
+        }
+
+        existingSplitContainer.getSecondaryContainer().finish(
+                false /* shouldFinishDependent */, mPresenter, wct, this);
+    }
+
     /**
      * Returns the topmost not finished container.
      */

libs/WindowManager/Jetpack/src/androidx/window/extensions/organizer/SplitPresenter.java

@@ -108,9 +108,10 @@ class SplitPresenter extends JetpackTaskFragmentOrganizer {
         // Set adjacent to each other so that the containers below will be invisible.
         wct.setAdjacentTaskFragments(
                 primaryContainer.getTaskFragmentToken(), secondaryContainer.getTaskFragmentToken());
-        applyTransaction(wct);
 
-        mController.registerSplit(primaryContainer, primaryActivity, secondaryContainer, rule);
+        mController.registerSplit(wct, primaryContainer, primaryActivity, secondaryContainer, rule);
+
+        applyTransaction(wct);
 
         return secondaryContainer;
     }
@@ -142,9 +143,10 @@ class SplitPresenter extends JetpackTaskFragmentOrganizer {
         // Set adjacent to each other so that the containers below will be invisible.
         wct.setAdjacentTaskFragments(
                 primaryContainer.getTaskFragmentToken(), secondaryContainer.getTaskFragmentToken());
-        applyTransaction(wct);
 
-        mController.registerSplit(primaryContainer, primaryActivity, secondaryContainer, rule);
+        mController.registerSplit(wct, primaryContainer, primaryActivity, secondaryContainer, rule);
+
+        applyTransaction(wct);
     }
 
     /**
@@ -202,20 +204,16 @@ class SplitPresenter extends JetpackTaskFragmentOrganizer {
         }
 
         TaskFragmentContainer secondaryContainer = mController.newContainer(null);
-        startActivityToSide(
-                primaryContainer.getTaskFragmentToken(),
-                primaryRectBounds,
-                launchingActivity,
-                secondaryContainer.getTaskFragmentToken(),
-                secondaryRectBounds,
-                activityIntent,
-                activityOptions);
+        final WindowContainerTransaction wct = new WindowContainerTransaction();
+        mController.registerSplit(wct, primaryContainer, launchingActivity, secondaryContainer,
+                rule);
+        startActivityToSide(wct, primaryContainer.getTaskFragmentToken(), primaryRectBounds,
+                launchingActivity, secondaryContainer.getTaskFragmentToken(), secondaryRectBounds,
+                activityIntent, activityOptions);
+        applyTransaction(wct);
 
         primaryContainer.setLastRequestedBounds(primaryRectBounds);
         secondaryContainer.setLastRequestedBounds(secondaryRectBounds);
-
-        mController.registerSplit(primaryContainer, launchingActivity, secondaryContainer,
-                rule);
     }
 
     /**