Add enter-animation-done callback for system windows
Existing hidden methods allow activities to be notified when their
windows have completed animating in. This change adds that capability
to system windows using a ViewTreeObserver callback since system
windows lack an activity token.
The first subsystem to use this is the UserSwitchingDialog which was
previously using a 250 msec timeout to dismiss the dialog. That
deadline was often missed leaving the user with no dialog on the
screen during the transition.
Fixes bug 16661752.
Change-Id: I70789e0d9c07112f275e76fb82850926305f290d
diff --git a/core/java/android/view/ViewTreeObserver.java b/core/java/android/view/ViewTreeObserver.java
index a9444b4..b85fec8 100644
--- a/core/java/android/view/ViewTreeObserver.java
+++ b/core/java/android/view/ViewTreeObserver.java
@@ -44,10 +44,15 @@
private CopyOnWriteArray<OnComputeInternalInsetsListener> mOnComputeInternalInsetsListeners;
private CopyOnWriteArray<OnScrollChangedListener> mOnScrollChangedListeners;
private CopyOnWriteArray<OnPreDrawListener> mOnPreDrawListeners;
+ private CopyOnWriteArray<OnWindowShownListener> mOnWindowShownListeners;
// These listeners cannot be mutated during dispatch
private ArrayList<OnDrawListener> mOnDrawListeners;
+ /** Remains false until #dispatchOnWindowShown() is called. If a listener registers after
+ * that the listener will be immediately called. */
+ private boolean mWindowShown;
+
private boolean mAlive = true;
/**
@@ -174,6 +179,19 @@
}
/**
+ * Interface definition for a callback noting when a system window has been displayed.
+ * This is only used for non-Activity windows. Activity windows can use
+ * Activity.onEnterAnimationComplete() to get the same signal.
+ * @hide
+ */
+ public interface OnWindowShownListener {
+ /**
+ * Callback method to be invoked when a non-activity window is fully shown.
+ */
+ void onWindowShown();
+ }
+
+ /**
* Parameters used with OnComputeInternalInsetsListener.
*
* We are not yet ready to commit to this API and support it, so
@@ -375,6 +393,14 @@
}
}
+ if (observer.mOnWindowShownListeners != null) {
+ if (mOnWindowShownListeners != null) {
+ mOnWindowShownListeners.addAll(observer.mOnWindowShownListeners);
+ } else {
+ mOnWindowShownListeners = observer.mOnWindowShownListeners;
+ }
+ }
+
observer.kill();
}
@@ -568,6 +594,45 @@
}
/**
+ * Register a callback to be invoked when the view tree window has been shown
+ *
+ * @param listener The callback to add
+ *
+ * @throws IllegalStateException If {@link #isAlive()} returns false
+ * @hide
+ */
+ public void addOnWindowShownListener(OnWindowShownListener listener) {
+ checkIsAlive();
+
+ if (mOnWindowShownListeners == null) {
+ mOnWindowShownListeners = new CopyOnWriteArray<OnWindowShownListener>();
+ }
+
+ mOnWindowShownListeners.add(listener);
+ if (mWindowShown) {
+ listener.onWindowShown();
+ }
+ }
+
+ /**
+ * Remove a previously installed window shown callback
+ *
+ * @param victim The callback to remove
+ *
+ * @throws IllegalStateException If {@link #isAlive()} returns false
+ *
+ * @see #addOnWindowShownListener(OnWindowShownListener)
+ * @hide
+ */
+ public void removeOnWindowShownListener(OnWindowShownListener victim) {
+ checkIsAlive();
+ if (mOnWindowShownListeners == null) {
+ return;
+ }
+ mOnWindowShownListeners.remove(victim);
+ }
+
+ /**
* <p>Register a callback to be invoked when the view tree is about to be drawn.</p>
* <p><strong>Note:</strong> this method <strong>cannot</strong> be invoked from
* {@link android.view.ViewTreeObserver.OnDrawListener#onDraw()}.</p>
@@ -854,6 +919,27 @@
}
/**
+ * Notifies registered listeners that the window is now shown
+ * @hide
+ */
+ @SuppressWarnings("unchecked")
+ public final void dispatchOnWindowShown() {
+ mWindowShown = true;
+ final CopyOnWriteArray<OnWindowShownListener> listeners = mOnWindowShownListeners;
+ if (listeners != null && listeners.size() > 0) {
+ CopyOnWriteArray.Access<OnWindowShownListener> access = listeners.start();
+ try {
+ int count = access.size();
+ for (int i = 0; i < count; i++) {
+ access.get(i).onWindowShown();
+ }
+ } finally {
+ listeners.end();
+ }
+ }
+ }
+
+ /**
* Notifies registered listeners that the drawing pass is about to start.
*/
public final void dispatchOnDraw() {