Disable Orientation Change

Re-Initiating Custom Camera, while doing change in Preview modes, from Landscape to Portrait or Portrait to Landscape, my Surface class code looks like this:

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
        }           
    }

}

May i know where i am doing wrong, what i missed in my code ?

回答1:

You have to handle configuration change for your app .

Add this line to your AndroidManifest.xml.

android:configChanges="keyboardHidden|orientation|screenSize"

This tells the system what configuration changes you are going to handle yourself - in this case by doing nothing.

Hope it helps ツ

回答2:

It's not clear from your question what you complain about, but you seem to only manipulate camera parameters, never calling mCamera.setParameters(parameters). This alone may cause confusion.

Using parameters.set("orientation", "landscape"); on devices that do not support this parameter may cause RuntimeException in mCamera.setParameters(parameters). Therefore, we usually use a separate try…catch around this setting.