How to set text property on keyDownHandler on TextInput in Flex 3 - apache-flex

Question

Simple and straight forward.
I extended a mx.controls.TextInput to create a custom component with a different behavior.
I'm trying to set the text property on the keyDownHandler(), and for some reason it doesn't work as I expected. The text on the component just kinda ignore the change.
I'm using Flex 3.6.
Down here is a simple example code that explains what's going on:
<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" xmlns:customcomponent="com.test.customcomponent.*">
<customcomponent:TextTest x="20" y="20"/>
</mx:Application>
And below de AS class:
package com.test.customcomponent
{
import flash.events.KeyboardEvent;
import mx.controls.TextInput;
public class TextTest extends TextInput
{
public function TextTest()
{
super();
}
override protected function keyDownHandler(event:KeyboardEvent):void{
text = "lol. It doesn't work";
}
}
}

Answer 1

You need to prevent the default key down event.
override protected function keyDownHandler(event:KeyboardEvent):void{
text = "lol. It doesn't work";
event.preventDefault();
event.stopImmediatePropagation();
event.stopPropagation()
}

Answer 2

In order to be able to prevent the default handling, you have to have a high enough priority on your handler (which keyDownHandler() does not have). This means you need to register your own method with priority > 0.
You can try like this:
public function MyTextInput() {
addEventListener(KeyboardEvent.KEY_DOWN, yourHandler,
false, EventPriority.BINDING, true);
...
}
private function yourHandler(event : KeyboardEvent) : void {
// stop further handling
event.preventDefault();
event.stopImmediatePropagation();
event.stopPropagation();
// do your work here
text = ...;
}