Android：将相机预览视为倾斜

Question

我制作了自定义相机应用程序。我正在获得倾斜的相机视图。所以我想知道正确和正常预览的解决方案。我使用了setDisplayOrientation（）方法。但没有结果。寻找有效的答案。

Compiling API是2.3 GingerBread！

提前致谢。

public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
private SurfaceHolder mHolder;
private Camera mCamera;
String TAG = "MyMsg";

public CameraPreview(Context context, Camera camera) {
    super(context);
    mCamera = camera;

    // Install a SurfaceHolder.Callback so we get notified when the
    // underlying surface is created and destroyed.
    mHolder = getHolder();
    mHolder.addCallback(this);
    // deprecated setting, but required on Android versions prior to 3.0
    mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}

public void surfaceCreated(SurfaceHolder holder) {

    // The Surface has been created, now tell the camera where to draw the preview.
    try {
        try {
            mCamera.stopPreview();
        } catch (Exception e){
          // ignore: tried to stop a non-existent preview
        }

        Log.d(TAG, "Surface Creation started");
        mCamera.setPreviewDisplay(holder);
        mCamera.startPreview();
    } catch (IOException e) {
        Log.d("MyMsg", "Error setting camera preview: " + e.getMessage());
    }
}

public void surfaceDestroyed(SurfaceHolder holder) {
    // empty. Take care of releasing the Camera preview in your activity.
}

public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
    // If your preview can change or rotate, take care of those events here.
    // Make sure to stop the preview before resizing or reformatting it.

    if (mHolder.getSurface() == null){
      // preview surface does not exist
      return;
    }

    // stop preview before making changes
    try {
        mCamera.stopPreview();
    } catch (Exception e){
      // ignore: tried to stop a non-existent preview
    }

    // set preview size and make any resize, rotate or
    // reformatting changes here
    // start preview with new settings
    try {
        mCamera.setPreviewDisplay(mHolder);
        mCamera.startPreview();

    } catch (Exception e){
        Log.d("MyMsg", "Error starting camera preview: " + e.getMessage());
    }
}

public static void setCameraDisplayOrientation(Activity activity,
        int cameraId, android.hardware.Camera camera) {
    android.hardware.Camera.CameraInfo info =
            new android.hardware.Camera.CameraInfo();
    android.hardware.Camera.getCameraInfo(cameraId, info);
    int rotation = activity.getWindowManager().getDefaultDisplay()
            .getRotation();
    int degrees = 0;
    switch (rotation) {
        case Surface.ROTATION_0: degrees = 0; break;
        case Surface.ROTATION_90: degrees = 90; break;
        case Surface.ROTATION_180: degrees = 180; break;
        case Surface.ROTATION_270: degrees = 270; break;
    }

    int result;
    if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
        result = (info.orientation + degrees) % 360;
        result = (360 - result) % 360;  // compensate the mirror
    } else {  // back-facing
        result = (info.orientation - degrees + 360) % 360;
    }
    camera.setDisplayOrientation(result);
}

@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
    // TODO Auto-generated method stub

}
}

`