# Key.isDown() imitation classes crashing processes? (Flex 3)

**URL:** <https://forum.kirupa.com/t/key-isdown-imitation-classes-crashing-processes-flex-3/271700>\
**Category:** flash\
**Created:** [September 26, 2008, 4:16pm UTC](https://forum.kirupa.com/t/key-isdown-imitation-classes-crashing-processes-flex-3/271700 "2008-09-26T16:16:52Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![jotapeh](https://avatars.discourse-cdn.com/v4/letter/j/8e7dd6/32.png) [@jotapeh](https://forum.kirupa.com/u/jotapeh)\
**Post date:** [September 26, 2008, 4:16pm UTC](https://forum.kirupa.com/t/key-isdown-imitation-classes-crashing-processes-flex-3/271700/1 "2008-09-26T16:16:52Z")

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Hi folks, been lurking around here for a couple weeks and as a means of learning Flex 3/AS3 I’ve been attacking various programming projects. My latest one is intended to be a very simple platform game but I’ve hit a roadblock.

stage.addEventListener(KeyboardEvent.KEY\_DOWN, keyDownHandler) seems to prevent any further code from executing in the program.

I have tried using senocular’s replacement classes after attempts to code my own failed, but it seems to do this regardless.

Does anyone have any ideas why this happens? If I add an event listener to the Application instead, it will not register any keydowns unless a textfield or something along those lines is present, which is no good to me.

_Basically_ I would just like to get all this KeyDown and KeyUp code out of my main application’s mxml file in a clean way.