Add TaskbarControllers#runAfterInit()

And use it in TaskbarModelCallbacks#commitItemsToUI(), which in rare cases can run during init() before other controllers (namely TaskbarStashController) have been initialized.

Test: call commitItemsToUI() in TaskbarModelCallbacks#init(), ensure no crash
Fixes: 204847702
Change-Id: Ib9df3ea91d41c76ad1d3392e43b444b8b4a91374
Merged-In: Ib9df3ea91d41c76ad1d3392e43b444b8b4a91374

quickstep/src/com/android/launcher3/taskbar/TaskbarControllers.java

@@ -19,6 +19,9 @@ import androidx.annotation.NonNull;
 
 import com.android.systemui.shared.rotation.RotationButtonController;
 
+import java.util.ArrayList;
+import java.util.List;
+
 /**
  * Hosts various taskbar controllers to facilitate passing between one another.
  */
@@ -43,6 +46,9 @@ public class TaskbarControllers {
     /** Do not store this controller, as it may change at runtime. */
     @NonNull public TaskbarUIController uiController = TaskbarUIController.DEFAULT;
 
+    private boolean mAreAllControllersInitialized;
+    private final List<Runnable> mPostInitCallbacks = new ArrayList<>();
+
     public TaskbarControllers(TaskbarActivityContext taskbarActivityContext,
             TaskbarDragController taskbarDragController,
             TaskbarNavButtonController navButtonController,
@@ -81,6 +87,8 @@ public class TaskbarControllers {
      * in constructors for now, as some controllers may still be waiting for init().
      */
     public void init(TaskbarSharedState sharedState) {
+        mAreAllControllersInitialized = false;
+
         taskbarDragController.init(this);
         navbarButtonsViewController.init(this);
         rotationButtonController.init();
@@ -92,6 +100,12 @@ public class TaskbarControllers {
         stashedHandleViewController.init(this);
         taskbarStashController.init(this, sharedState);
         taskbarEduController.init(this);
+
+        mAreAllControllersInitialized = true;
+        for (Runnable postInitCallback : mPostInitCallbacks) {
+            postInitCallback.run();
+        }
+        mPostInitCallbacks.clear();
     }
 
     /**
@@ -108,4 +122,17 @@ public class TaskbarControllers {
         stashedHandleViewController.onDestroy();
         taskbarAutohideSuspendController.onDestroy();
     }
+
+    /**
+     * If all controllers are already initialized, runs the given callback immediately. Otherwise,
+     * queues it to run after calling init() on all controllers. This should likely be used in any
+     * case where one controller is telling another controller to do something inside init().
+     */
+    public void runAfterInit(Runnable callback) {
+        if (mAreAllControllersInitialized) {
+            callback.run();
+        } else {
+            mPostInitCallbacks.add(callback);
+        }
+    }
 }

quickstep/src/com/android/launcher3/taskbar/TaskbarModelCallbacks.java

@@ -184,9 +184,12 @@ public class TaskbarModelCallbacks implements
         }
         mContainer.updateHotseatItems(hotseatItemInfos);
 
-        mControllers.taskbarStashController.updateStateForFlag(
-                TaskbarStashController.FLAG_STASHED_IN_APP_EMPTY, isHotseatEmpty);
-        mControllers.taskbarStashController.applyState();
+        final boolean finalIsHotseatEmpty = isHotseatEmpty;
+        mControllers.runAfterInit(() -> {
+            mControllers.taskbarStashController.updateStateForFlag(
+                    TaskbarStashController.FLAG_STASHED_IN_APP_EMPTY, finalIsHotseatEmpty);
+            mControllers.taskbarStashController.applyState();
+        });
     }
 
     @Override