Android - setBackgroundResource on Button - android

I have some buttons which i set the background with setBackgroundResource(R.drawable.cal_box_center); and the problem I'm having is that my background is a gradient which has this banding effect (annoying) and I've read that in order to remove this you'll need to set the Bitmap.Config.ARGB_8888. I looked into the API and the way to do this is to use decodeStream etc, but how can i use setBackgroundResource and still set the Config to ARGB_8888?
Thanks in advance.


You can use this code snippet:
// create button
Button btn = new Button(getApplicationContext());
//decode the resource(You can also use decodeStream and other decode method of
//BitmapFactory)
Bitmap btm = BitmapFactory.decodeResource(getResources(), R.drawable.cal_box_center);
//create another copy of your bitmap and specify Config
Bitmap newBtm = btm.copy(Bitmap.Config.ARGB_8888, true);
//use your newBtm to create a BitmapDrawable
BitmapDrawable btmDrwble = new BitmapDrawable(newBtm);
// finally set the drawable as your button's background
btn.setBackgroundDrawable(btmDrwble);

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