windows - Spark WindowedApplication，监听keyUp事件

Question

我有一个 WindowedApplication，我需要监视 keyUp 以便我可以在按下转义键时关闭应用程序。但是，我的代码不起作用:

<s:WindowedApplication xmlns:fx="http://ns.adobe.com/mxml/2009" 
                       xmlns:s="library://ns.adobe.com/flex/spark" 
                       xmlns:mx="library://ns.adobe.com/flex/mx"
                       keyUp="windowedapplication1_keyUpHandler(event)">

<fx:Script>
        <![CDATA[   

            protected function windowedapplication1_keyUpHandler(event:KeyboardEvent):void
            {
                //Monitor key press {ESC}
                if(event.keyCode == 27){
                    exit();
                }
                else{
                    trace("key = " + event.keyCode);
                }
            }   

        ]]>
</fx:Script>

似乎这个事件根本没有触发，我什至试图覆盖 keyUpHandler 并追踪一些信息，但没有。

Answer 1

我找到了 this similar question在 Adob​​e 论坛上，它帮助解决了问题。

我通过监听 applicationComplete 然后在处理程序中将 keyUp 监听器附加到 stage 来解决。

<s:WindowedApplication xmlns:fx="http://ns.adobe.com/mxml/2009" 
                       xmlns:s="library://ns.adobe.com/flex/spark" 
                       xmlns:mx="library://ns.adobe.com/flex/mx"
                       applicationComplete="init()">

<fx:Script>
        <![CDATA[   

            protected function init():void
            {
                stage.addEventListener(KeyboardEvent.KEY_UP, windowedapplication1_keyUpHandler);
            }

            protected function windowedapplication1_keyUpHandler(event:KeyboardEvent):void
            {
                //Monitor key press {ESC}
                if(event.keyCode == 27){
                    exit();
                }
                else{
                    trace("key = " + event.keyCode);
                }
            }       

        ]]>
</fx:Script>