Home | History | Annotate | Download | only in view 
      1 /*
      2  * Copyright (C) 2016 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package android.view;
     18 
     19 import android.annotation.NonNull;
     20 import android.util.Log;
     21 import android.os.Looper;
     22 import android.os.MessageQueue;
     23 
     24 import com.android.internal.util.VirtualRefBasePtr;
     25 
     26 import java.lang.NullPointerException;
     27 import java.lang.ref.WeakReference;
     28 import java.lang.SuppressWarnings;
     29 
     30 /**
     31  * Provides streaming access to frame stats information from the rendering
     32  * subsystem to apps.
     33  *
     34  * @hide
     35  */
     36 public class FrameMetricsObserver {
     37     private MessageQueue mMessageQueue;
     38 
     39     private WeakReference<Window> mWindow;
     40 
     41     private FrameMetrics mFrameMetrics;
     42 
     43     /* package */ Window.OnFrameMetricsAvailableListener mListener;
     44     /* package */ VirtualRefBasePtr mNative;
     45 
     46     /**
     47      * Creates a FrameMetricsObserver
     48      *
     49      * @param looper the looper to use when invoking callbacks
     50      */
     51     FrameMetricsObserver(@NonNull Window window, @NonNull Looper looper,
     52             @NonNull Window.OnFrameMetricsAvailableListener listener) {
     53         if (looper == null) {
     54             throw new NullPointerException("looper cannot be null");
     55         }
     56 
     57         mMessageQueue = looper.getQueue();
     58         if (mMessageQueue == null) {
     59             throw new IllegalStateException("invalid looper, null message queue\n");
     60         }
     61 
     62         mFrameMetrics = new FrameMetrics();
     63         mWindow = new WeakReference<>(window);
     64         mListener = listener;
     65     }
     66 
     67     // Called by native on the provided Handler
     68     @SuppressWarnings("unused")
     69     private void notifyDataAvailable(int dropCount) {
     70         final Window window = mWindow.get();
     71         if (window != null) {
     72             mListener.onFrameMetricsAvailable(window, mFrameMetrics, dropCount);
     73         }
     74     }
     75 }
     76