android允许录屏代码demo

以下是一个简单的示例代码，可以实现在Android 5.0及以上版本中使用MediaProjection API进行屏幕录制：

public class ScreenRecorder {

    private static final String TAG = "ScreenRecorder";

    private MediaProjection mMediaProjection;
    private VirtualDisplay mVirtualDisplay;
    private MediaRecorder mMediaRecorder;

    private int mScreenWidth;
    private int mScreenHeight;
    private int mScreenDensity;

    private boolean mIsRecording;

    public ScreenRecorder(MediaProjection mediaProjection, int screenWidth, int screenHeight, int screenDensity) {
        mMediaProjection = mediaProjection;
        mScreenWidth = screenWidth;
        mScreenHeight = screenHeight;
        mScreenDensity = screenDensity;
    }

    public boolean isRecording() {
        return mIsRecording;
    }

    public void startRecording(String filePath) {
        mMediaRecorder = new MediaRecorder();

        try {
            mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.SURFACE);
            mMediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
            mMediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.H264);
            mMediaRecorder.setVideoEncodingBitRate(512 * 1000);
            mMediaRecorder.setVideoFrameRate(30);
            mMediaRecorder.setVideoSize(mScreenWidth, mScreenHeight);
            mMediaRecorder.setOutputFile(filePath);
            mMediaRecorder.prepare();
        } catch (IOException e) {
            e.printStackTrace();
        }

        mVirtualDisplay = mMediaProjection.createVirtualDisplay(TAG, mScreenWidth, mScreenHeight, mScreenDensity,
                DisplayManager.VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR, mMediaRecorder.getSurface(), null, null);

        mMediaRecorder.start();
        mIsRecording = true;
    }

    public void stopRecording() {
        if (mMediaRecorder != null) {
            mMediaRecorder.stop();
            mMediaRecorder.release();
            mMediaRecorder = null;
        }

        if (mVirtualDisplay != null) {
            mVirtualDisplay.release();
            mVirtualDisplay = null;
        }

        if (mMediaProjection != null) {
            mMediaProjection.stop();
            mMediaProjection = null;
        }

        mIsRecording = false;
    }
}

使用该类进行屏幕录制的示例代码如下：

private MediaProjectionManager mMediaProjectionManager;
private ScreenRecorder mScreenRecorder;

private void startScreenRecord() {
    if (mMediaProjectionManager == null) {
        mMediaProjectionManager = (MediaProjectionManager) getSystemService(Context.MEDIA_PROJECTION_SERVICE);
    }

    if (mScreenRecorder == null) {
        int screenWidth = getResources().getDisplayMetrics().widthPixels;
        int screenHeight = getResources().getDisplayMetrics().heightPixels;
        int screenDensity = getResources().getDisplayMetrics().densityDpi;
        mScreenRecorder = new ScreenRecorder(mMediaProjectionManager.getMediaProjection(Activity.RESULT_OK, mResultData),
                screenWidth, screenHeight, screenDensity);
    }

    if (!mScreenRecorder.isRecording()) {
        mScreenRecorder.startRecording(Environment.getExternalStorageDirectory() + "/test.mp4");
    }
}

private void stopScreenRecord() {
    if (mScreenRecorder != null && mScreenRecorder.isRecording()) {
        mScreenRecorder.stopRecording();
    }
}

需要注意的是，使用该示例代码进行屏幕录制需要先获取悬浮窗权限和录音权限。同时，还需要在AndroidManifest.xml文件中添加以下权限：

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />