commit ac439e57a795d48e287ea51a9bd999244a9b0e65
author Craig Mautner <cmautner@google.com> Fri Sep 21 08:58:34 2012 -0700
committer Craig Mautner <cmautner@google.com> Fri Sep 21 08:58:34 2012 -0700
tree 7061e3a90a16b86aa2e78e447dc04d8654d368aa
parent ced8d21f5abf46d128264a3039f7a84155d2b9dc

Eliminate potential for NPE in WindowAnimator.

Fixes bug 7209850.

Change-Id: I8c8751ab240ea389a2a779c94c05fe786ca8762a

services/java/com/android/server/wm/WindowAnimator.java

diff --git a/services/java/com/android/server/wm/WindowAnimator.java b/services/java/com/android/server/wm/WindowAnimator.java
index 0a4e6d3..377e89c 100644
--- a/services/java/com/android/server/wm/WindowAnimator.java
+++ b/services/java/com/android/server/wm/WindowAnimator.java
@@ -139,10 +139,8 @@
     }
 
     void addDisplayLocked(final int displayId) {
-        DisplayContentsAnimator displayAnimator = getDisplayContentsAnimatorLocked(displayId);
-        displayAnimator.mWindowAnimationBackgroundSurface =
-                new DimSurface(mService.mFxSession, displayId);
-        displayAnimator.mDimAnimator = new DimAnimator(mService.mFxSession, displayId);
+        // Create the DisplayContentsAnimator object by retrieving it.
+        getDisplayContentsAnimatorLocked(displayId);
         if (displayId == Display.DEFAULT_DISPLAY) {
             mInitialized = true;
         }
@@ -787,7 +785,7 @@
     private DisplayContentsAnimator getDisplayContentsAnimatorLocked(int displayId) {
         DisplayContentsAnimator displayAnimator = mDisplayContentsAnimators.get(displayId);
         if (displayAnimator == null) {
-            displayAnimator = new DisplayContentsAnimator();
+            displayAnimator = new DisplayContentsAnimator(displayId);
             mDisplayContentsAnimators.put(displayId, displayAnimator);
         }
         return displayAnimator;
@@ -801,11 +799,17 @@
         return getDisplayContentsAnimatorLocked(displayId).mScreenRotationAnimation;
     }
 
-    private static class DisplayContentsAnimator {
+    private class DisplayContentsAnimator {
         WinAnimatorList mWinAnimators = new WinAnimatorList();
-        DimAnimator mDimAnimator = null;
+        final DimAnimator mDimAnimator;
         DimAnimator.Parameters mDimParams = null;
-        DimSurface mWindowAnimationBackgroundSurface = null;
+        final DimSurface mWindowAnimationBackgroundSurface;
         ScreenRotationAnimation mScreenRotationAnimation = null;
+
+        public DisplayContentsAnimator(int displayId) {
+            mDimAnimator = new DimAnimator(mService.mFxSession, displayId);
+            mWindowAnimationBackgroundSurface =
+                    new DimSurface(mService.mFxSession, displayId);
+        }
     }
 }