Do I want to receive mouseEnter: and mouseLeave: when the button is up and the hand is empty? The default response is false, except if you have added sensitivity to mouseEnter: or mouseLeave:, using the on:send:to: mechanism.
Return true if I want to receive mouseEnterDragging: and mouseLeaveDragging: when the hand drags something over me (button up or button down), or when the mouse button is down but there is no mouseDown recipient. The default response is false, except if you have added sensitivity to mouseEnterLaden: or mouseLeaveLaden:, using the on:send:to: mechanism.
Return true if the receiver wishes to accept the given morph, which is being dropped by a hand in response to the given event. Note that for a successful drop operation both parties need to agree. The symmetric check is done automatically via aMorph wantsToBeDroppedInto: self.