Merge "Camera: Use a single handler thread for device state callbacks" into udc-dev

core/java/android/hardware/camera2/CameraManager.java

@@ -142,24 +142,18 @@ public final class CameraManager {
                     PackageManager.PERMISSION_GRANTED;
         }
 
-        mHandlerThread = new HandlerThread(TAG);
-        mHandlerThread.start();
-        mHandler = new Handler(mHandlerThread.getLooper());
         mFoldStateListener = new FoldStateListener(context);
         try {
-            context.getSystemService(DeviceStateManager.class)
-                    .registerCallback(new HandlerExecutor(mHandler), mFoldStateListener);
+            context.getSystemService(DeviceStateManager.class).registerCallback(
+                    new HandlerExecutor(CameraManagerGlobal.get().getDeviceStateHandler()),
+                    mFoldStateListener);
         } catch (IllegalStateException e) {
             Log.v(TAG, "Failed to register device state listener!");
             Log.v(TAG, "Device state dependent characteristics updates will not be functional!");
-            mHandlerThread.quitSafely();
-            mHandler = null;
             mFoldStateListener = null;
         }
     }
 
-    private HandlerThread mHandlerThread;
-    private Handler mHandler;
     private FoldStateListener mFoldStateListener;
 
     /**
@@ -1645,6 +1639,9 @@ public final class CameraManager {
         private ICameraService mCameraService;
         private boolean mHasOpenCloseListenerPermission = false;
 
+        private HandlerThread mDeviceStateHandlerThread;
+        private Handler mDeviceStateHandler;
+
         // Singleton, don't allow construction
         private CameraManagerGlobal() { }
 
@@ -1658,6 +1655,18 @@ public final class CameraManager {
             return gCameraManager;
         }
 
+        public Handler getDeviceStateHandler() {
+            synchronized(mLock) {
+                if (mDeviceStateHandlerThread == null) {
+                    mDeviceStateHandlerThread = new HandlerThread(TAG);
+                    mDeviceStateHandlerThread.start();
+                    mDeviceStateHandler = new Handler(mDeviceStateHandlerThread.getLooper());
+                }
+
+                return mDeviceStateHandler;
+            }
+        }
+
         @Override
         public IBinder asBinder() {
             return this;