Top-Level Functions and Methods 19 keyUp() Availability Flash MX 2004. Usage function keyUp() { // statements } Parameters None. Returns Nothing. Description Function; called when the extensible tool is active and a key is released. Example The following example displays a message in the Output panel when the extensible tool is active and a key is released. function keyUp() { fl.trace("Key is released"); } See also keyDown() mouseDoubleClick() Availability Flash MX 2004. Usage function mouseDoubleClick() { // statements } Parameters None. Returns Nothing. Description Function; called when the extensible tool is active and the mouse button is double-clicked on the Stage. Example The following example displays a message in the Output panel when the extensible tool is active and the mouse button is double-clicked.