NavigationMenuItemView.java 文件源码

private StateListDrawable createDefaultBackground() {
    TypedValue value = new TypedValue();
    if (!getContext().getTheme().resolveAttribute(R.attr.colorControlHighlight, value, true)) {
        return null;
    }
    StateListDrawable drawable = new StateListDrawable();
    drawable.addState(CHECKED_STATE_SET, new ColorDrawable(value.data));
    drawable.addState(EMPTY_STATE_SET, new ColorDrawable(0));
    return drawable;
}