Android 截屏实现、屏幕截图、MediaProjection、ImageReader_break妖_android实时获取屏幕图像

大大的周 02-07 5369

1. 第一步：调起系统捕获屏幕的Intent MainActivity: public void goCaptureIntent() { //第一步.调起系统捕获屏幕的Intent mMediaProjectionManager = (MediaProjectionManager) getSystemService(MEDIA_PROJECTION_SERVICE); Intent captureIntent = mMediaProjectionManager.createScreenCaptureIntent(); startActivityForResult(captureIntent, SCREEN_SHOT_CODE); } 2. 第二步：通过startForegroundService来获取mediaProjection

注：sdk 28以及以下可以直接在Activity中获取，29以及以上在Activity中获取会报错

MainActivity: @RequiresApi(api = Build.VERSION_CODES.O) @Override public void onActivityResult(int requestCode, int resultCode, Intent data) { super.onActivityResult(requestCode, resultCode, data); if(requestCode==SCREEN_SHOT_CODE && resultCode == RESULT_OK){ //第二步通过startForegroundService来获取mediaProjection Intent service = new Intent(this, ScreenShootService.class); service.putExtra("code", resultCode); service.putExtra("data", data); service.putExtra("width", getScreenWidth(this)); service.putExtra("height", getScreenHeight(this)); startForegroundService(service); } } 3.?第三步：获取mediaProjection

注：AndroidManifest.xml中注册的service要加上以下属性

?第三步的代码：

ScreenShootService： @Override public int onStartCommand(Intent intent, int flags, int startId) { int resultCode = intent.getIntExtra("code", -1); Intent data = intent.getParcelableExtra("data"); width = intent.getIntExtra("width",1080); height = intent.getIntExtra("height",1920); notification(); //第三步：获取mediaProjection MediaProjectionManager mMediaProjectionManager = (MediaProjectionManager) getSystemService(MEDIA_PROJECTION_SERVICE); MediaProjection mediaProjection = mMediaProjectionManager.getMediaProjection(resultCode, data); if (mediaProjection == null) { Log.e(TAG, "media projection is null"); } Bitmap bitmap = screenShot(mediaProjection); EventBus.getDefault().post(bitmap); return super.onStartCommand(intent, flags, startId); } ?4.?第四步：通过mediaProjection截图获取Image ScreenShootService： //第四步；通过mediaProjection截图获取Image public Bitmap screenShot(MediaProjection mediaProjection){ Objects.requireNonNull(mediaProjection); @SuppressLint("WrongConstant") ImageReader imageReader = ImageReader.newInstance(width, height, PixelFormat.RGBA_8888, 60); VirtualDisplay virtualDisplay = mediaProjection.createVirtualDisplay("screen", width, height, 1, DisplayManager.VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR,imageReader.getSurface(), null, null); //取现在最新的图片 SystemClock.sleep(1000); //取最新的图片 Image image = imageReader.acquireLatestImage(); // Image image = imageReader.acquireNextImage(); //释放 virtualDisplay,不释放会报错 virtualDisplay.release(); return image2Bitmap(image); } 5. 第五步：将Image转为Bitmap ScreenShootService： //第五步:将Image转为Bitmap public static Bitmap image2Bitmap(Image image) { if (image == null) { System.out.println("image 为空"); return null; } int width = image.getWidth(); int height = image.getHeight(); final Image.Plane[] planes = image.getPlanes(); final ByteBuffer buffer = planes[0].getBuffer(); int pixelStride = planes[0].getPixelStride(); int rowStride = planes[0].getRowStride(); int rowPadding = rowStride - pixelStride * width; Bitmap bitmap = Bitmap.createBitmap(width+ rowPadding / pixelStride , height, Bitmap.Config.ARGB_8888); bitmap.copyPixelsFromBuffer(buffer); //截取图片 // Bitmap cutBitmap = Bitmap.createBitmap(bitmap,0,0,width/2,height/2); //压缩图片 // Matrix matrix = new Matrix(); // matrix.setScale(0.5F, 0.5F); // System.out.println(bitmap.isMutable()); // bitmap = Bitmap.createBitmap(bitmap, 0, 0, width, height, matrix, false); image.close(); return bitmap; } 6.?第六步：展示截图结果

这里是通过EventBust从Service传到了Activity

MainActivity： //接收service返回的bitmap图片数据 @Subscribe(threadMode = ThreadMode.MAIN)//在ui线程执行 public void onMoonEvent(Bitmap bitmap){ //第六步：展示截图结果 imgShowImage.setBackground(new BitmapDrawable(bitmap)); } 异常处理1.?E/BufferQueueProducer: [ImageReader-2340x1080f1m1-24598-0](id:601600000001,api:1,p:1080,c:24598) dequeueBuffer: BufferQueue has been abandoned

分析：异常：BufferQueue已经被丢弃了，还在使用

说明有在可能是截图中使用到的某个对象被GC了，BufferQueue的对象大概有三个ImageReader 、VirtualDisplay 和 Image，Image在截图万之后已经close掉了，然后尝试截图后分别对ImageReader和VirtualDisplay进行释放，ImageReader释放问题依然存在，VirtualDisplay释放解决了该问题。

VirtualDisplay virtualDisplay = mediaProjection.createVirtualDisplay("screen", width, height, 1, DisplayManager.VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR,imageReader.getSurface(), null, null); ... 使用完Image之后... ... virtualDisplay.release(); ?异常处理2：Media projections require a foreground service of type ServiceInfo.FOREGROUND_SERVICE_TYPE_MEDIA_PROJECTION

sdk版本产生的适配问题

两种解决方案：

方案一：将sdk降低到28或者以下

?方案二：即需要使用 startForegroundService

也就是上面demo中使用到的方法

Activity： public void goCaptureIntent() { //第一步.调起系统捕获屏幕的Intent mMediaProjectionManager = (MediaProjectionManager) getSystemService(MEDIA_PROJECTION_SERVICE); Intent captureIntent = mMediaProjectionManager.createScreenCaptureIntent(); startActivityForResult(captureIntent, SCREEN_SHOT_CODE); } @RequiresApi(api = Build.VERSION_CODES.O) @Override public void onActivityResult(int requestCode, int resultCode, Intent data) { super.onActivityResult(requestCode, resultCode, data); if(requestCode==SCREEN_SHOT_CODE && resultCode == RESULT_OK){ //第二步通过startForegroundService来获取mediaProjection Intent service = new Intent(this, ScreenShootService.class); service.putExtra("code", resultCode); service.putExtra("data", data); service.putExtra("width", getScreenWidth(this)); service.putExtra("height", getScreenHeight(this)); startForegroundService(service); } } Service： @Override public int onStartCommand(Intent intent, int flags, int startId) { int resultCode = intent.getIntExtra("code", -1); Intent data = intent.getParcelableExtra("data"); width = intent.getIntExtra("width",1080); height = intent.getIntExtra("height",1920); notification(); //第二步：创建mediaProjection MediaProjectionManager mMediaProjectionManager = (MediaProjectionManager) getSystemService(MEDIA_PROJECTION_SERVICE); MediaProjection mediaProjection = mMediaProjectionManager.getMediaProjection(resultCode, data); if (mediaProjection == null) { Log.e(TAG, "media projection is null"); } Bitmap bitmap = screenShot(mediaProjection); EventBus.getDefault().post(bitmap); return super.onStartCommand(intent, flags, startId); } AndroidManifest.xml： <service android:name=".ScreenShootService" android:enabled="true" android:foregroundServiceType="mediaProjection">

?最终效果图：

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