Access resource defined in theme and attrs.xml android

I think you can get the Drawable with this code:

TypedArray a = getTheme().obtainStyledAttributes(R.style.AppTheme, new int[] {R.attr.homeIcon});     
int attributeResourceId = a.getResourceId(0, 0);
Drawable drawable = getResources().getDrawable(attributeResourceId);
a.recycle();