Button dropshadow at "Doelklank" screen

[BramBleys]

The buttons still have a dropshadow. The code to fix this:
TypedValue value = new TypedValue(); getApplicationContext().getTheme().resolveAttribute(R.style.Widget_AppCompat_Button_Borderless, value, true);
button.setBackgroundResource(value.resourceId);

The problem is that this overwrites our custom button style. You can't have 2 backgroundResources on 1 button.