UIHANDLER OnMouseUp

Releasing a mouse button after pressing it overtop a Frame. (self, button)

Arguments

 * self : - The widget on which the mouse button was earlier pressed.
 * button : - "LeftButton", "RightButton", "MiddleButton", "Button4", "Button5", ..., "ButtonN"

Details

 * Fires even if the cursor is moved and released elsewhere, unless.
 * Controlled by or ; however, setting OnMouseUp implictly triggers.
 * Fires before, , and (exclusive to  widget type).