Swaps the z-order (front-to-back order) of the two specified child objects.
All other child objects in the display object container remain in the same index positions.
Source
void swapChildren(DisplayObject child1, DisplayObject child2) {
int index1 = getChildIndex(child1);
int index2 = getChildIndex(child2);
if (index1 == -1 || index2 == -1) {
throw new ArgumentError("The supplied DisplayObject must be a child of the caller.");
} else {
swapChildrenAt(index1, index2);
}
}