Refactor InsettableFrameLayout/DragLayer and add StateListener interface.

Bug: 65387919
Change-Id: I5eb94c0f3962d44f63af3efc92d852e019bba711

src/com/android/launcher3/InsettableFrameLayout.java

@@ -9,8 +9,7 @@ import android.view.ViewDebug;
 import android.view.ViewGroup;
 import android.widget.FrameLayout;
 
-public class InsettableFrameLayout extends FrameLayout implements
-    ViewGroup.OnHierarchyChangeListener, Insettable {
+public class InsettableFrameLayout extends FrameLayout implements Insettable {
 
     @ViewDebug.ExportedProperty(category = "launcher")
     protected Rect mInsets = new Rect();
@@ -21,7 +20,6 @@ public class InsettableFrameLayout extends FrameLayout implements
 
     public InsettableFrameLayout(Context context, AttributeSet attrs) {
         super(context, attrs);
-        setOnHierarchyChangeListener(this);
     }
 
     public void setFrameLayoutChildInsets(View child, Rect newInsets, Rect oldInsets) {
@@ -95,12 +93,8 @@ public class InsettableFrameLayout extends FrameLayout implements
     }
 
     @Override
-    public void onChildViewAdded(View parent, View child) {
+    public void onViewAdded(View child) {
+        super.onViewAdded(child);
         setFrameLayoutChildInsets(child, mInsets, new Rect());
     }
-
-    @Override
-    public void onChildViewRemoved(View parent, View child) {
-    }
-
 }

src/com/android/launcher3/LauncherStateManager.java

@@ -25,7 +25,6 @@ import android.os.Handler;
 import android.os.Looper;
 import android.view.View;
 
-import com.android.launcher3.allapps.AllAppsTransitionController;
 import com.android.launcher3.anim.AnimationLayerSet;
 import com.android.launcher3.anim.AnimationSuccessListener;
 import com.android.launcher3.anim.AnimatorPlaybackController;
@@ -83,6 +82,8 @@ public class LauncherStateManager {
     private StateHandler[] mStateHandlers;
     private LauncherState mState = NORMAL;
 
+    private StateListener mStateListener;
+
     public LauncherStateManager(Launcher l) {
         mUiHandler = new Handler(Looper.getMainLooper());
         mLauncher = l;
@@ -99,6 +100,10 @@ public class LauncherStateManager {
         return mStateHandlers;
     }
 
+    public void setStateListener(StateListener stateListener) {
+        mStateListener = stateListener;
+    }
+
     /**
      * @see #goToState(LauncherState, boolean, Runnable)
      */
@@ -157,6 +162,9 @@ public class LauncherStateManager {
             for (StateHandler handler : getStateHandlers()) {
                 handler.setState(state);
             }
+            if (mStateListener != null) {
+                mStateListener.onStateSetImmediately(state);
+            }
             mLauncher.getUserEventDispatcher().resetElapsedContainerMillis();
 
             // Run any queued runnable
@@ -210,6 +218,17 @@ public class LauncherStateManager {
             public void onAnimationStart(Animator animation) {
                 // Change the internal state only when the transition actually starts
                 setState(state);
+                if (mStateListener != null) {
+                    mStateListener.onStateTransitionStart(state);
+                }
+            }
+
+            @Override
+            public void onAnimationEnd(Animator animation) {
+                super.onAnimationEnd(animation);
+                if (mStateListener != null) {
+                    mStateListener.onStateTransitionComplete(mState);
+                }
             }
 
             @Override
@@ -304,4 +323,15 @@ public class LauncherStateManager {
         void setStateWithAnimation(LauncherState toState, AnimationLayerSet layerViews,
                 AnimatorSet anim, AnimationConfig config);
     }
+
+    public interface StateListener {
+
+        /**
+         * Called when the state is set without an animation.
+         */
+        void onStateSetImmediately(LauncherState state);
+
+        void onStateTransitionStart(LauncherState toState);
+        void onStateTransitionComplete(LauncherState finalState);
+    }
 }

src/com/android/launcher3/dragndrop/DragLayer.java

@@ -703,13 +703,14 @@ public class DragLayer extends InsettableFrameLayout {
     }
 
     @Override
-    public void onChildViewAdded(View parent, View child) {
-        super.onChildViewAdded(parent, child);
+    public void onViewAdded(View child) {
+        super.onViewAdded(child);
         updateChildIndices();
     }
 
     @Override
-    public void onChildViewRemoved(View parent, View child) {
+    public void onViewRemoved(View child) {
+        super.onViewRemoved(child);
         updateChildIndices();
     }