ThemeUtils.java 文件源码

public static boolean containsNinePatch(Drawable drawable) {
    drawable = getWrapperDrawable(drawable);
    if (drawable instanceof NinePatchDrawable
            || drawable instanceof InsetDrawable
            || drawable instanceof LayerDrawable) {
        return true;
    } else if (drawable instanceof StateListDrawable) {
        final DrawableContainer.DrawableContainerState containerState = ((DrawableContainer.DrawableContainerState) drawable.getConstantState());
        //can't get containState from drawable which is containing DrawableWrapperDonut
        //https://code.google.com/p/android/issues/detail?id=169920
        if (containerState == null) {
            return true;
        }
        for (Drawable dr : containerState.getChildren()) {
            dr = getWrapperDrawable(dr);
            if (dr instanceof NinePatchDrawable
                    || dr instanceof InsetDrawable
                    || dr instanceof LayerDrawable) {
                return true;
            }
        }
    }
    return false;
}