PXDrawableUtil.java 文件源码

/**
 * Check if two Drawables are equal. A regular check for a Drawable equals
 * just checks for the instance reference, while this check is doing a
 * deeper equals when dealing with {@link DrawableContainer} instances. In
 * these cases, the method will run equals on each of the child drawables in
 * the container (order is importance as well).
 * 
 * @param d1
 * @param d2
 * @return <code>true</code> if the drawables are equal, <code>false</code>
 *         otherwise.
 */
public static boolean isEquals(Drawable d1, Drawable d2) {
    if (d1 == d2) {
        return true;
    }
    if (d1 == null || d2 == null) {
        return false;
    }
    if (d1 instanceof DrawableContainer && d2 instanceof DrawableContainer) {
        // Try to match the content of those containers
        DrawableContainerState containerState1 = (DrawableContainerState) ((DrawableContainer) d1)
                .getConstantState();
        DrawableContainerState containerState2 = (DrawableContainerState) ((DrawableContainer) d2)
                .getConstantState();

        return Arrays.equals(containerState1.getChildren(), containerState2.getChildren());
    }
    return d1.equals(d2);
}