android - Android 5.0 如何延迟录屏？

Question

在我运行以下代码后，会显示一个对话框，提示是否开始捕捉屏幕(请参见图片)，在我单击“立即开始”按钮后，应用程序会立即录制屏幕。

我希望app在我点击START NOW按钮后可以延迟5秒录屏，并在手机屏幕上显示倒计时信息(如:5s后开始录，4s后开始录，...) ，我该怎么做？谢谢!

public class MainActivity extends Activity {

    private static final String TAG = "MainActivity";
    private static final int PERMISSION_CODE = 1;
    private int mScreenDensity;
    private MediaProjectionManager mProjectionManager;
    private static final int DISPLAY_WIDTH = 480;
    private static final int DISPLAY_HEIGHT = 640;
    private MediaProjection mMediaProjection;
    private VirtualDisplay mVirtualDisplay;
    private MediaProjectionCallback mMediaProjectionCallback;
    private ToggleButton mToggleButton;
    private MediaRecorder mMediaRecorder;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        DisplayMetrics metrics = new DisplayMetrics();
        getWindowManager().getDefaultDisplay().getMetrics(metrics);
        mScreenDensity = metrics.densityDpi;

        mMediaRecorder = new MediaRecorder();
        initRecorder();
        prepareRecorder();

        mProjectionManager = (MediaProjectionManager) getSystemService
                (Context.MEDIA_PROJECTION_SERVICE);

        mToggleButton = (ToggleButton) findViewById(R.id.toggle);
        mToggleButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                onToggleScreenShare(v);
            }
        });

        mMediaProjectionCallback = new MediaProjectionCallback();
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        if (mMediaProjection != null) {
            mMediaProjection.stop();
            mMediaProjection = null;
        }
    }

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode != PERMISSION_CODE) {
            Log.e(TAG, "Unknown request code: " + requestCode);
            return;
        }
        if (resultCode != RESULT_OK) {
            Toast.makeText(this,
                    "Screen Cast Permission Denied", Toast.LENGTH_SHORT).show();
            mToggleButton.setChecked(false);
            return;
        }
        mMediaProjection = mProjectionManager.getMediaProjection(resultCode, data);
        mMediaProjection.registerCallback(mMediaProjectionCallback, null);
        mVirtualDisplay = createVirtualDisplay();
        mMediaRecorder.start();
    }

    public void onToggleScreenShare(View view) {
        if (((ToggleButton) view).isChecked()) {
            shareScreen();
        } else {
            mMediaRecorder.stop();
            mMediaRecorder.reset();
            Log.v(TAG, "Recording Stopped");
            stopScreenSharing();
            initRecorder();
            prepareRecorder();
        }
    }

    private void shareScreen() {
        if (mMediaProjection == null) {
            startActivityForResult(mProjectionManager.createScreenCaptureIntent(), PERMISSION_CODE);
            return;
        }
        mVirtualDisplay = createVirtualDisplay();
        mMediaRecorder.start();
    }

    private void stopScreenSharing() {
        if (mVirtualDisplay == null) {
            return;
        }
        mVirtualDisplay.release();
        //mMediaRecorder.release();
    }

    private VirtualDisplay createVirtualDisplay() {
        return mMediaProjection.createVirtualDisplay("MainActivity",
                DISPLAY_WIDTH, DISPLAY_HEIGHT, mScreenDensity,
                DisplayManager.VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR,
                mMediaRecorder.getSurface(), null /*Callbacks*/, null /*Handler*/);
    }

    private class MediaProjectionCallback extends MediaProjection.Callback {
        @Override
        public void onStop() {
            if (mToggleButton.isChecked()) {
                mToggleButton.setChecked(false);
                mMediaRecorder.stop();
                mMediaRecorder.reset();
                Log.v(TAG, "Recording Stopped");
                initRecorder();
                prepareRecorder();
            }
            mMediaProjection = null;
            stopScreenSharing();
            Log.i(TAG, "MediaProjection Stopped");
        }
    }

    private void prepareRecorder() {
        try {
            mMediaRecorder.prepare();
        } catch (IllegalStateException e) {
            e.printStackTrace();
            finish();
        } catch (IOException e) {
            e.printStackTrace();
            finish();
        }
    }

    private void initRecorder() {
        mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
        mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.SURFACE);
        mMediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
        mMediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.H264);
        mMediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
        mMediaRecorder.setVideoEncodingBitRate(512 * 1000);
        mMediaRecorder.setVideoFrameRate(30);
        mMediaRecorder.setVideoSize(DISPLAY_WIDTH, DISPLAY_HEIGHT);
        mMediaRecorder.setOutputFile("/sdcard/capture.mp4");
    }
}

Answer 1

使用CountDownTimer来延迟:

    private CountDownTimer myCount;
            myCount = new CountDownTimer(5000,1000) {

                @Override
                public void onTick(long millisUntilFinished) {
                    //Show seconds 1 to 5
                }

                @Override
                public void onFinish() {
                    //Start Catturing Screen displayed 
                }
            };