commit a0a7a7440e860c61c8261c5009dbe351869896b3
author Jason Monk <jmonk@google.com> Tue Apr 22 09:23:19 2014 -0400
committer Jason Monk <jmonk@google.com> Tue Apr 22 10:33:33 2014 -0400
tree af50f49d1a1d49da0b09f335bdcbd8a646b89d7d
parent f2a791a798ce24d81f3410c83873087690db4ffd

Add synchronization to DeferredBindRunnables

Seems that on occasion the list is being iterated on while being
modified.  To fix this added synchronization to all modifications
to the list as well as iterating on a copy of the list to cut
down on time holding the lock.

Bug: 12885709
Change-Id: I4287bdedbeb8e438b49c1f79b44819a752c28a69

src/com/android/launcher3/LauncherModel.java

diff --git a/src/com/android/launcher3/LauncherModel.java b/src/com/android/launcher3/LauncherModel.java
index e5eca62..0efd172 100644
--- a/src/com/android/launcher3/LauncherModel.java
+++ b/src/com/android/launcher3/LauncherModel.java
@@ -498,7 +498,9 @@
         }
 
         // Clear any deferred bind runnables
-        mDeferredBindRunnables.clear();
+        synchronized (mDeferredBindRunnables) {
+            mDeferredBindRunnables.clear();
+        }
         // Remove any queued bind runnables
         mHandler.cancelAllRunnablesOfType(MAIN_THREAD_BINDING_RUNNABLE);
         // Unbind all the workspace items
@@ -1315,7 +1317,9 @@
 
             // Clear any deferred bind-runnables from the synchronized load process
             // We must do this before any loading/binding is scheduled below.
-            mDeferredBindRunnables.clear();
+            synchronized (mDeferredBindRunnables) {
+                mDeferredBindRunnables.clear();
+            }
 
             // Don't bother to start the thread if we know it's not going to do anything
             if (mCallbacks != null && mCallbacks.get() != null) {
@@ -1337,10 +1341,15 @@
     void bindRemainingSynchronousPages() {
         // Post the remaining side pages to be loaded
         if (!mDeferredBindRunnables.isEmpty()) {
-            for (final Runnable r : mDeferredBindRunnables) {
+            Runnable[] deferredBindRunnables = null;
+            synchronized (mDeferredBindRunnables) {
+                deferredBindRunnables = mDeferredBindRunnables.toArray(
+                        new Runnable[mDeferredBindRunnables.size()]);
+                mDeferredBindRunnables.clear();
+            }
+            for (final Runnable r : deferredBindRunnables) {
                 mHandler.post(r, MAIN_THREAD_BINDING_RUNNABLE);
             }
-            mDeferredBindRunnables.clear();
         }
     }
 
@@ -2367,7 +2376,9 @@
                     }
                 };
                 if (postOnMainThread) {
-                    deferredBindRunnables.add(r);
+                    synchronized (deferredBindRunnables) {
+                        deferredBindRunnables.add(r);
+                    }
                 } else {
                     runOnMainThread(r, MAIN_THREAD_BINDING_RUNNABLE);
                 }
@@ -2384,7 +2395,9 @@
                     }
                 };
                 if (postOnMainThread) {
-                    deferredBindRunnables.add(r);
+                    synchronized (deferredBindRunnables) {
+                        deferredBindRunnables.add(r);
+                    }
                 } else {
                     runOnMainThread(r, MAIN_THREAD_BINDING_RUNNABLE);
                 }
@@ -2506,7 +2519,9 @@
 
             // Load all the remaining pages (if we are loading synchronously, we want to defer this
             // work until after the first render)
-            mDeferredBindRunnables.clear();
+            synchronized (mDeferredBindRunnables) {
+                mDeferredBindRunnables.clear();
+            }
             bindWorkspaceItems(oldCallbacks, otherWorkspaceItems, otherAppWidgets, otherFolders,
                     (isLoadingSynchronously ? mDeferredBindRunnables : null));
 
@@ -2528,7 +2543,9 @@
                 }
             };
             if (isLoadingSynchronously) {
-                mDeferredBindRunnables.add(r);
+                synchronized (mDeferredBindRunnables) {
+                    mDeferredBindRunnables.add(r);
+                }
             } else {
                 runOnMainThread(r, MAIN_THREAD_BINDING_RUNNABLE);
             }