在flex中监听鼠标右键事件,提示 TypeError Error 2007 参数type不能为空。

at flash.events::EventDispatcher/addEventListener()
at com.waylau.eagleos.components::DesktopExplorer/service_resultHandler()[D:\workspaceFB47\com.waylau.eagleos_0.9.5\src\com\waylau\eagleos\components\DesktopExplorer.mxml:59]
at com.waylau.eagleos.components::DesktopExplorer/__service_result()[D:\workspaceFB47\com.waylau.eagleos_0.9.5\src\com\waylau\eagleos\components\DesktopExplorer.mxml:214]
at flash.events::EventDispatcher/dispatchEventFunction()
at flash.events::EventDispatcher/dispatchEvent()
at HTTPOperation/http://www.adobe.com/2006/flex/mx/internal::dispatchRpcEvent()[E:\dev\4.y\frameworks\projects\rpc\src\mx\rpc\http\HTTPService.as:993]
at mx.rpc::AbstractInvoker/http://www.adobe.com/2006/flex/mx/internal::resultHandler()[E:\dev\4.y\frameworks\projects\rpc\src\mx\rpc\AbstractInvoker.as:318]
at mx.rpc::Responder/result()[E:\dev\4.y\frameworks\projects\rpc\src\mx\rpc\Responder.as:56]
at mx.rpc::AsyncRequest/acknowledge()[E:\dev\4.y\frameworks\projects\rpc\src\mx\rpc\AsyncRequest.as:84]
at DirectHTTPMessageResponder/completeHandler()[E:\dev\4.y\frameworks\projects\rpc\src\mx\messaging\channels\DirectHTTPChannel.as:451]
at flash.events::EventDispatcher/dispatchEventFunction()
at flash.events::EventDispatcher/dispatchEvent()
at flash.net::URLLoader/onComplete()