1 /* 2 * Copyright (C) 2019 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.graphics.Rect; 20 import android.os.IBinder; 21 22 import com.android.internal.util.Preconditions; 23 24 import java.util.concurrent.Executor; 25 26 /** 27 * Listener for sampling the result of the screen composition. 28 * {@hide} 29 */ 30 public abstract class CompositionSamplingListener { 31 32 private final long mNativeListener; 33 private final Executor mExecutor; 34 CompositionSamplingListener(Executor executor)35 public CompositionSamplingListener(Executor executor) { 36 mExecutor = executor; 37 mNativeListener = nativeCreate(this); 38 } 39 40 @Override finalize()41 protected void finalize() throws Throwable { 42 try { 43 if (mNativeListener != 0) { 44 unregister(this); 45 nativeDestroy(mNativeListener); 46 } 47 } finally { 48 super.finalize(); 49 } 50 } 51 52 /** 53 * Reports a luma sample from the registered region. 54 */ onSampleCollected(float medianLuma)55 public abstract void onSampleCollected(float medianLuma); 56 57 /** 58 * Registers a sampling listener. 59 */ register(CompositionSamplingListener listener, int displayId, IBinder stopLayer, Rect samplingArea)60 public static void register(CompositionSamplingListener listener, 61 int displayId, IBinder stopLayer, Rect samplingArea) { 62 Preconditions.checkArgument(displayId == Display.DEFAULT_DISPLAY, 63 "default display only for now"); 64 nativeRegister(listener.mNativeListener, stopLayer, samplingArea.left, samplingArea.top, 65 samplingArea.right, samplingArea.bottom); 66 } 67 68 /** 69 * Unregisters a sampling listener. 70 */ unregister(CompositionSamplingListener listener)71 public static void unregister(CompositionSamplingListener listener) { 72 nativeUnregister(listener.mNativeListener); 73 } 74 75 /** 76 * Dispatch the collected sample. 77 * 78 * Called from native code on a binder thread. 79 */ dispatchOnSampleCollected(CompositionSamplingListener listener, float medianLuma)80 private static void dispatchOnSampleCollected(CompositionSamplingListener listener, 81 float medianLuma) { 82 listener.mExecutor.execute(() -> listener.onSampleCollected(medianLuma)); 83 } 84 nativeCreate(CompositionSamplingListener thiz)85 private static native long nativeCreate(CompositionSamplingListener thiz); nativeDestroy(long ptr)86 private static native void nativeDestroy(long ptr); nativeRegister(long ptr, IBinder stopLayer, int samplingAreaLeft, int top, int right, int bottom)87 private static native void nativeRegister(long ptr, IBinder stopLayer, 88 int samplingAreaLeft, int top, int right, int bottom); nativeUnregister(long ptr)89 private static native void nativeUnregister(long ptr); 90 } 91