问题:
FlashPlayer插件对不同的浏览器有不同的版本,从其是否支持调试功能可分为:可调试插件和不可调试插件,两者主要区别有:
1) You can connect to it with the remote debugger The (right-click) context menu will include an option to "Show Redraw Regions", which lets you verify how much of your content is being redrawn each frame.
2) The debug player will show a pop-up error message for uncaught exceptions (in the regular player they would fail silently.
3) There are a handful of AS3 commands which only work in the debug player, such as System.gc(). See the System reference.
4) Basically the debug player has a sprinkling of features to make it more suited for development, and anyone developing their own content should probably be using it.
特别注意第2点,debug player在遇见未被不做错误时会弹出错误消息框,而regular player则不会报错。鉴于此,用户在使用flex应用时,往往会碰到不可遇见的怪现象,如用户点了保存按钮没反应,点了查询按钮没反应等。事实上,用户点击保存按钮的时候,程序执行过程中出错了,但是开发人员为捕捉错误,而不可调试player却未报错。
解决:
要解决此怪象,本人认为可以有3种解决方案。
1)所有flex 的代码全部进行try catch处理,估计程序员会变疯;
2)所有用户请使用带调试的插件,估计不是用户会变疯就是支持人员会变疯;
3)进行flex全局错误处理。
很明显,进行flex全局错误处理是比较好的解决方案,但是flex全局错误处理只支持flashplayer10.1及以后的版本,SDK需要4.1版本。因此,对于哪些sdk和flashplayer如有严格要求的flex应用就爱莫能助了。下述为flex全局处理的adobe的官方文档的一个例子:
遗憾的是flex新提供的错误全局处理机制,只支持application及sub application,对于module却不支持。
<?xml version="1.0" encoding="utf-8"?> <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/halo" applicationComplete="applicationCompleteHandler();"> <fx:Script> <![CDATA[ import flash.events.ErrorEvent; import flash.events.MouseEvent; import flash.events.UncaughtErrorEvent; private function applicationCompleteHandler():void { loaderInfo.uncaughtErrorEvents.addEventListener(UncaughtErrorEvent.UNCAUGHT_ERROR, uncaughtErrorHandler); } private function uncaughtErrorHandler(event:UncaughtErrorEvent):void { if (event.error is Error) { var error:Error = event.error as Error; // do something with the error } else if (event.error is ErrorEvent) { var errorEvent:ErrorEvent = event.error as ErrorEvent; // do something with the error } else { // a non-Error, non-ErrorEvent type was thrown and uncaught } } private function clickHandler(event:MouseEvent):void { throw new Error("Gak!"); } ]]> </fx:Script> <s:Button label="Cause Error" click="clickHandler(event);"/> </s:WindowedApplication> |