As far as the mouse is concerned:
Create a button and place it.
Create a Text Object - Put over Button
Event:
On Mouse Click
->If Mouse Over <font color=blue>BUTTON</font>
-->Do whatever
It automatically will see all objects under the mouse, but YOU specify which object to ACTUALLY see in the event. It ignores all else.
I think it works the same with touch... Is that what you are asking, or am I to tired to understand?