Prevent MediaProjection object from being lost on killing the Application

Question

I am using MediaProjection to take screenshot.This is what I am doing.I created an overlay icon using service.On clicking the overlay icon a screenshot is taken.The problem is that whenever the Application is killed either by pressing back button or manually by swiping it the MediaProjection object is lost.Is there a way to maintain the MediaProjection and avoiding requesting for MediaProjection each time application is killed. I have already seen this but I am still unable to do it.

In my Mainactivity Onclick contains startActivityForResult and the resulting onActivityResult is as follows:

 @Override
protected void onActivityResult(final int requestCode,final int resultCode,final Intent data)
{
    if (requestCode == requestcode)
    {
        if (resultCode == RESULT_OK)
        {
            Singelton.setScreenshotPermission((Intent) data.clone());
            Singelton.putmanger(mediaProjectionManager);

        }else if (resultCode==RESULT_CANCELED) {
            Singelton.setScreenshotPermission(null);
        }
    }
}

The Singelton class is as follows:

protected static void setScreenshotPermission(final Intent permissionIntent)
{
    screenshotPermission = permissionIntent;
//screenshotPermission becomes null once the application is killed
}

public static MediaProjection getData()
{
    return (mediaProjection);
}

public static void getScreenshotPermission()
{
    if (screenshotPermission != null)
    {
        Log.d("screenshotpermisson", "screenshotPermission != null ");
        if(mediaProjection!=null)
        {
            Log.d("mediaprojection", "mediaprojection != null ");
            mediaProjection.stop();
            mediaProjection = null;
        }
        mediaProjection = mediaProjectionManager.getMediaProjection(Activity.RESULT_OK, (Intent) screenshotPermission.clone());
    }
   else
    {
    //Here I need to request for media projection again without starting activity
    }

}

My Service class for overlay icon handles click as follows:

 public void createDisplay()
{
    if (mediaProjection == null)
    {
        Singelton.getScreenshotPermission();
        mediaProjection = Singelton.getData();
    }

    mImageReader = ImageReader.newInstance(width, height, PixelFormat.RGBA_8888, 1);
    vd = mediaProjection.createVirtualDisplay("screen-mirror", width, height, mDensity, DisplayManager.VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR, mImageReader.getSurface(), null, null);
    mImageReader.setOnImageAvailableListener(new ImageReader.OnImageAvailableListener(){..}
}

I am new to android and having a hard time figuring this out.Any help will be appreciated.

An app moving to the background isn't necessarily killed. It might be killed to free up memory, or it might sit quietly until it's un-paused. Is there a reason why you can't release the media projection at pause time, and recreate it at resume? — fadden, Apr 17 '16 at 15:56

score 1 · Answer 1 · edited May 23 '17 at 12:02

Just re-create the media projection as fadden implied in his comment. Since every time your service is killed the associated overlay is also killed with it therefore you have to re-create the media projection anyway when restarting the service.

You already doing fine by not consuming the original intent and instead using an clone as answered here https://stackoverflow.com/a/33892817/3918978 .

However if the permission or the MediaProjection shouldn't be valid anymore just get a new one (start an activity asking for it).

Prevent MediaProjection object from being lost on killing the Application

1 Answers1