禁用方向更改

重新启动自定义相机，同时在“预览”模式下进行更改（从“风景”到“人像”或从“人像”到“风景”），我的Surface类代码如下所示：

PreviewSurface.java：-

public class PreviewSurface extends SurfaceView implements
SurfaceHolder.Callback {

    public static final String LOG_TAG = "CameraPreview";
    private SurfaceHolder mSurfaceHolder;

    private Camera mCamera;

    // Constructor that obtains context and camera
    @SuppressWarnings("deprecation")
    public PreviewSurface(Context context, Camera camera) {
        super(context);
        this.mCamera = camera;

        this.mSurfaceHolder = this.getHolder();
        this.mSurfaceHolder.addCallback(this);
        this.mSurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        this.mSurfaceHolder.setFixedSize(100, 100);
    }

    @Override
    public void surfaceCreated(SurfaceHolder surfaceHolder) {
        try {       
            Camera.Parameters parameters = mCamera.getParameters();
            if (this.getResources().getConfiguration().orientation != Configuration.ORIENTATION_LANDSCAPE) 
            {
                 parameters.set("orientation", "portrait");
                 mCamera.setDisplayOrientation(90);
                 parameters.setRotation(90);
                 mCamera.setPreviewDisplay(surfaceHolder);
                 mCamera.startPreview();
            }
            else 
            {
                 // This is an undocumented although widely known feature
                 parameters.set("orientation", "landscape");
                 // For Android 2.2 and above
                 mCamera.setDisplayOrientation(0);
                 // Uncomment for Android 2.0 and above
                 parameters.setRotation(0);
            }
            mCamera.setPreviewDisplay(surfaceHolder);
            mCamera.startPreview();

        } catch (IOException e) {
            // left blank for now
        }
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder surfaceHolder) {
        mCamera.stopPreview();
        mCamera.release();
    }

    @Override
    public void surfaceChanged(SurfaceHolder surfaceHolder, int format,
            int width, int height) {

        try {       
            Camera.Parameters parameters = mCamera.getParameters();
            if (this.getResources().getConfiguration().orientation != Configuration.ORIENTATION_LANDSCAPE) {
                 parameters.set("orientation", "portrait");
                 mCamera.setDisplayOrientation(90);
                 parameters.setRotation(90);

            }
                 else {
                      // This is an undocumented although widely known feature
                      parameters.set("orientation", "landscape");
                      // For Android 2.2 and above
                      mCamera.setDisplayOrientation(0);
                      // Uncomment for Android 2.0 and above
                      parameters.setRotation(0);
            }
            mCamera.setPreviewDisplay(surfaceHolder);
            mCamera.startPreview();

        } catch (IOException e) {
            // left blank for now
        }           
    }

}

我可以知道我在哪里做错了，我在代码中错过了什么吗？