diff --git a/src/com/android/launcher3/compat/PackageInstallerCompatVL.java b/src/com/android/launcher3/compat/PackageInstallerCompatVL.java
index a84bf02..601f04c 100644
--- a/src/com/android/launcher3/compat/PackageInstallerCompatVL.java
+++ b/src/com/android/launcher3/compat/PackageInstallerCompatVL.java
@@ -20,6 +20,7 @@
 import android.content.pm.PackageInstaller;
 import android.content.pm.PackageInstaller.SessionCallback;
 import android.content.pm.PackageInstaller.SessionInfo;
+import android.os.Handler;
 import android.util.Log;
 import android.util.SparseArray;
 
@@ -29,15 +30,18 @@
 import java.util.ArrayList;
 import java.util.HashSet;
 
-public class PackageInstallerCompatVL extends PackageInstallerCompat {
+public class PackageInstallerCompatVL extends PackageInstallerCompat implements Runnable {
 
     private static final String TAG = "PackageInstallerCompatVL";
     private static final boolean DEBUG = false;
 
+    // All updates to these sets must happen on the {@link #mWorker} thread.
     private final SparseArray<SessionInfo> mPendingReplays = new SparseArray<SessionInfo>();
     private final HashSet<String> mPendingBadgeUpdates = new HashSet<String>();
+
     private final PackageInstaller mInstaller;
     private final IconCache mCache;
+    private final Handler mWorker;
 
     private boolean mResumed;
     private boolean mBound;
@@ -46,16 +50,23 @@
         mInstaller = context.getPackageManager().getPackageInstaller();
         LauncherAppState.setApplicationContext(context.getApplicationContext());
         mCache = LauncherAppState.getInstance().getIconCache();
+        mWorker = new Handler();
 
         mResumed = false;
         mBound = false;
 
-        mInstaller.registerSessionCallback(mCallback);
+        mInstaller.registerSessionCallback(mCallback, mWorker);
 
         // On start, send updates for all active sessions
-        for (SessionInfo info : mInstaller.getAllSessions()) {
-            mPendingReplays.append(info.getSessionId(), info);
-        }
+        mWorker.post(new Runnable() {
+
+            @Override
+            public void run() {
+                for (SessionInfo info : mInstaller.getAllSessions()) {
+                    mPendingReplays.append(info.getSessionId(), info);
+                }
+            }
+        });
     }
 
     @Override
@@ -87,7 +98,7 @@
     @Override
     public void onFinishBind() {
         mBound = true;
-        replayUpdates(null);
+        mWorker.post(this);
     }
 
     @Override
@@ -98,7 +109,7 @@
     @Override
     public void onResume() {
         mResumed = true;
-        replayUpdates(null);
+        mWorker.post(this);
     }
 
     @Override
@@ -106,6 +117,12 @@
         // No op
     }
 
+    @Override
+    public void run() {
+        // Called on mWorker thread.
+        replayUpdates(null);
+    }
+
     private void replayUpdates(PackageInstallInfo newInfo) {
         if (DEBUG) Log.d(TAG, "updates resumed");
         if (!mResumed || !mBound) {