Android 摄像机预览画面不断切换到风景中

我制作了一个摄像机应用程序，它包含一个摄像机预览和一个按钮（开始/停止）。 我希望我的应用程序在纵向模式下工作，但我的预览旋转90度时，我尝试这样做（顺便说一句景观工程正常）。 我尝试过设置方向（90度），它可以工作，但是我可以看到它从90度视图切换到0度视图（正常视图）。 有没有办法让我的相机预览始终保持纵向

我在网上任何地方都找不到任何解决办法

public class MainActivity extends Activity{

private Camera myCamera;
private MyCameraSurfaceView myCameraSurfaceView;
private MediaRecorder mediaRecorder;

Button myButton;
SurfaceHolder surfaceHolder;
boolean recording;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    recording = false;

    setContentView(R.layout.activity_main);

    //Get Camera for preview
    myCamera = getCameraInstance();
    if(myCamera == null){
        Toast.makeText(MainActivity.this,
                "Fail to get Camera",
                Toast.LENGTH_LONG).show();
    }


    myCameraSurfaceView = new MyCameraSurfaceView(this, myCamera);
    FrameLayout myCameraPreview = (FrameLayout)findViewById(R.id.videoview);
    myCameraPreview.addView(myCameraSurfaceView);


    myButton = (Button)findViewById(R.id.mybutton);
    myButton.setOnClickListener(myButtonOnClickListener);
}

Button.OnClickListener myButtonOnClickListener
        = new Button.OnClickListener(){

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        if(recording){
            // stop recording and release camera
            mediaRecorder.stop();  // stop the recording
            releaseMediaRecorder(); // release the MediaRecorder object
            myButton.setText("START");
            recording = false;
            //Exit after saved
            //finish();
        }else{
            myCamera.setDisplayOrientation(90);
            //Release Camera before MediaRecorder start
            releaseCamera();

            if(!prepareMediaRecorder()){
                Toast.makeText(MainActivity.this,
                        "Fail in prepareMediaRecorder()!\n - Ended -",
                        Toast.LENGTH_LONG).show();
                finish();
            }

            mediaRecorder.start();
            recording = true;
            myButton.setText("STOP");

        }
    }};

private Camera getCameraInstance(){
// TODO Auto-generated method stub
    Camera c = null;
    try {
        c = Camera.open(); // attempt to get a Camera instance
    }
    catch (Exception e){
        // Camera is not available (in use or does not exist)
    }
    return c; // returns null if camera is unavailable
}

private boolean prepareMediaRecorder(){
    myCamera = getCameraInstance();
    mediaRecorder = new MediaRecorder();

    myCamera.unlock();
    mediaRecorder.setCamera(myCamera);

    mediaRecorder.setAudioSource(MediaRecorder.AudioSource.CAMCORDER);
    mediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);

    mediaRecorder.setProfile(CamcorderProfile.get(CamcorderProfile.QUALITY_HIGH));

    mediaRecorder.setOutputFile("/sdcard/videocapture_example.mp4");
    //mediaRecorder.setMaxDuration(60000); // Set max duration 60 sec.
    //mediaRecorder.setMaxFileSize(5000000); // Set max file size 5M

    mediaRecorder.setPreviewDisplay(myCameraSurfaceView.getHolder().getSurface());

    try {
        mediaRecorder.prepare();
    } catch (IllegalStateException e) {
        releaseMediaRecorder();
        return false;
    } catch (IOException e) {
        releaseMediaRecorder();
        return false;
    }
    return true;

}

@Override
protected void onPause() {
    super.onPause();
    releaseMediaRecorder();       // if you are using MediaRecorder, release it first
    releaseCamera();              // release the camera immediately on pause event
}

private void releaseMediaRecorder(){
    if (mediaRecorder != null) {
        mediaRecorder.reset();   // clear recorder configuration
        mediaRecorder.release(); // release the recorder object
        mediaRecorder = null;
        myCamera.lock();           // lock camera for later use
    }
}

private void releaseCamera(){
    if (myCamera != null){
        myCamera.release();        // release the camera for other applications
        myCamera = null;
    }
}
}