Protect volumepanel slider creation from race condition.
It is possible for 2 different threads to poke the mStreamControls at the same time,
causing the monkey bug mentioned in the bug report below.
Bug: 6411852
Couldn't think of any other reason Stream type 3 (MUSIC) wouldn't exist in the list.
It's possible that a programmatic call came in at the same time as the volume key press.
Synchronizing blocks where the mStreamControls are populated and accessed.
Change-Id: Ifedec6b0f8bad9634cb9e079fda785c433bdb7a7
diff --git a/core/java/android/view/VolumePanel.java b/core/java/android/view/VolumePanel.java
index 78984e0..5ffc2c3 100644
--- a/core/java/android/view/VolumePanel.java
+++ b/core/java/android/view/VolumePanel.java
@@ -437,8 +437,10 @@
public void postVolumeChanged(int streamType, int flags) {
if (hasMessages(MSG_VOLUME_CHANGED)) return;
- if (mStreamControls == null) {
- createSliders();
+ synchronized (this) {
+ if (mStreamControls == null) {
+ createSliders();
+ }
}
removeMessages(MSG_FREE_RESOURCES);
obtainMessage(MSG_VOLUME_CHANGED, streamType, flags).sendToTarget();
@@ -450,8 +452,10 @@
public void postMuteChanged(int streamType, int flags) {
if (hasMessages(MSG_VOLUME_CHANGED)) return;
- if (mStreamControls == null) {
- createSliders();
+ synchronized (this) {
+ if (mStreamControls == null) {
+ createSliders();
+ }
}
removeMessages(MSG_FREE_RESOURCES);
obtainMessage(MSG_MUTE_CHANGED, streamType, flags).sendToTarget();
@@ -471,10 +475,12 @@
if (LOGD) Log.d(TAG, "onVolumeChanged(streamType: " + streamType + ", flags: " + flags + ")");
if ((flags & AudioManager.FLAG_SHOW_UI) != 0) {
- if (mActiveStreamType != streamType) {
- reorderSliders(streamType);
+ synchronized (this) {
+ if (mActiveStreamType != streamType) {
+ reorderSliders(streamType);
+ }
+ onShowVolumeChanged(streamType, flags);
}
- onShowVolumeChanged(streamType, flags);
}
if ((flags & AudioManager.FLAG_PLAY_SOUND) != 0 && ! mRingIsSilent) {