android 录屏及截图

【实例简介】

Android 5.0 屏幕录制
从 Android 4.4 开始支持手机端本地录屏，但首先需要获取 root 权限才行，Android 5.0 引入 MediaProject， 可以不用 root 就可以录屏，但需要弹权限获取窗口，需要用户允许才行，这里主要介绍 Android 5.0 利用 MediaProject 在非 root 情况下实现屏幕录制。

基本原理
在 Android 5.0，Google 终于开放了视频录制的接口，其实严格来说，是屏幕采集的接口，也就是 MediaProjection 和 MediaProjectionManager。

【实例截图】

【核心代码】

public class MainActivity extends AppCompatActivity { private static final int RECORDER_CODE = 0;  private static final String TAG = "TAG";   int width;  int height;  int dpi;   MediaProjectionManager projectionManager;  MediaProjection mediaProjection;  MediaCodec mediaCodec;  MediaMuxer mediaMuxer;   Surface surface;  VirtualDisplay virtualDisplay;  private MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();  private int videoTrackIndex = -1;   String filePath;  private AtomicBoolean mQuit = new AtomicBoolean(false);  private boolean muxerStarted = false;    @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP) @Override  protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState);  setContentView(R.layout.activity_main);   DisplayMetrics metric = new DisplayMetrics();  getWindowManager().getDefaultDisplay().getMetrics(metric);  width = 720;  height = 1280;  dpi = 1;    File file = null;  if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.N) {
            file = new File(this.getDataDir().getPath(),  "record-"  width  "x"  height  "-"  System.currentTimeMillis() ".avc");  } filePath = file.getAbsolutePath();  Log.e(TAG, "onCreate: " filePath );   mMP4Path =filePath;   projectionManager = (MediaProjectionManager) getSystemService(MEDIA_PROJECTION_SERVICE);  } @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP) @Override  protected void onActivityResult(int requestCode, int resultCode, Intent data) { mediaProjection = projectionManager.getMediaProjection(resultCode,data);  new Thread() { @Override  public void run() { try { try {
                        prepareEncoder();  mediaMuxer = new MediaMuxer(filePath, MediaMuxer.OutputFormat.MUXER_OUTPUT_MPEG_4);   } catch (IOException e) { throw new RuntimeException(e);  } virtualDisplay = mediaProjection.createVirtualDisplay(TAG  "-display",  width, height, dpi, DisplayManager.VIRTUAL_DISPLAY_FLAG_PUBLIC,  surface, null, null);   recordVirtualDisplay();    } finally {
                    release();  }
            }
        }.start();   Toast.makeText(this, "Recorder is running...", Toast.LENGTH_SHORT).show();  //    moveTaskToBack(true);  } @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP) private void recordVirtualDisplay() { while (!mQuit.get()) { int index = mediaCodec.dequeueOutputBuffer(bufferInfo, 10000);  if (index == MediaCodec.INFO_OUTPUT_FORMAT_CHANGED) {
                resetOutputFormat();  } else if (index >= 0) {
                encodeToVideoTrack(index);  mediaCodec.releaseOutputBuffer(index, false);  }
        }
    } @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP) private void encodeToVideoTrack(int index) {
        ByteBuffer encodedData = mediaCodec.getOutputBuffer(index);   if ((bufferInfo.flags & MediaCodec.BUFFER_FLAG_CODEC_CONFIG) != 0) { bufferInfo.size = 0;  } if (bufferInfo.size == 0) {
            encodedData = null;  } if (encodedData != null) {
            encodedData.position(bufferInfo.offset);  encodedData.limit(bufferInfo.offset  bufferInfo.size);  mediaMuxer.writeSampleData(videoTrackIndex, encodedData, bufferInfo);  }
    } @RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2) private void resetOutputFormat() {
        MediaFormat newFormat = mediaCodec.getOutputFormat();  videoTrackIndex = mediaMuxer.addTrack(newFormat);  mediaMuxer.start();  muxerStarted = true;  } @RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2) private void prepareEncoder() throws IOException {
        MediaFormat format = MediaFormat.createVideoFormat("video/avc", width, height);  format.setInteger(MediaFormat.KEY_COLOR_FORMAT,  MediaCodecInfo.CodecCapabilities.COLOR_FormatSurface);  format.setInteger(MediaFormat.KEY_BIT_RATE, 6000000);  format.setInteger(MediaFormat.KEY_FRAME_RATE, 30);  format.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, 10);   mediaCodec = MediaCodec.createEncoderByType("video/avc");  mediaCodec.configure(format, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);  surface = mediaCodec.createInputSurface();  mediaCodec.start();  } @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP) public void StartRecorder(View view) {
        startActivityForResult(projectionManager.createScreenCaptureIntent(),RECORDER_CODE);  } public void StopRecorder(View view) { mQuit.set(true);  Toast.makeText(this, "Recorder stop", Toast.LENGTH_SHORT).show();  } @RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2) private void release() { if (mediaCodec != null) { mediaCodec.stop();  mediaCodec.release();  mediaCodec = null;  } if (virtualDisplay != null) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) { virtualDisplay.release();  }
        } if (mediaProjection != null) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { mediaProjection.stop();  }
        } if (mediaMuxer != null) { mediaMuxer.release();  mediaMuxer = null;  }
    } private static String mMP4Path;  VideoView mVideoView;  MediaController mMediaController;