我正在尝试将一个textarea添加到SkinnablePopUpContainer，但运行它会给我一个错误。 如果我将textarea更改为例如代码运行良好的标签：
<s:SkinnablePopUpContainer " " width="244" height="150">
<fx:Declarations></fx:Declarations>
<s:TextArea width="98%" editable="false" text="blah"/>
错误：
ArgumentError：错误＃2025：提供的DisplayObject必须是调用者的子级。 在flash.display :: DisplayObjectContainer / getChildIndex（） 在mx.managers :: SystemManager / http：//www.adobe.com/2006/flex/mx/internal :: rawChildren_getChildIndex（）[E：\ dev \ 4.y \ frameworks \ projects \ framework \ src \ mx \经理\ SystemManager.as：2187] 在mx.managers :: SystemRawChildrenList / getChildIndex（）[E：\ dev \ 4.y \ frameworks \ projects \ framework \ src \ mx \ managers \ SystemRawChildrenList.as：181] 在spark.components.supportClasses :: StyleableStageText / getFormIndex（）[E：\ dev \ 4.y \ frameworks \ projects \ mobilecomponents \ src \ spark \ components \ supportClasses \ StyleableStageText.as:1956] 在spark.components.supportClasses :: StyleableStageText / findTopmostForm（）[E：\ dev \ 4.y \ frameworks \ projects \ mobilecomponents \ src \ spark \ components \ supportClasses \ StyleableStageText.as:1933] 在spark.components.supportClasses :: StyleableStageText / updateProxyImageForTopmostForm（）[E：\ dev \ 4.y \ frameworks \ projects \ mobilecomponents \ src \ spark \ components \ supportClasses \ StyleableStageText.as：2172] 在spark.components.supportClasses :: StyleableStageText / commitProperties（）[E：\ dev \ 4.y \ frameworks \ projects \ mobilecomponents \ src \ spark \ components \ supportClasses \ StyleableStageText.as:1510] 在mx.core :: UIComponent / validateProperties（）[E：\ dev \ 4.y \ frameworks \ projects \ framework \ src \ mx \ core \ UIComponent.as:8219] 在mx.managers :: LayoutManager / validateClient（）[E：\ dev \ 4.y \ frameworks \ projects \ framework \ src \ mx \ managers \ LayoutManager.as：957] 在mx.managers :: PopUpManagerImpl / addPopUp（）[E：\ dev \ 4.y \ frameworks \ projects \ framework \ src \ mx \ managers \ PopUpManagerImpl.as：382] 在mx.managers :: PopUpManager $ / addPopUp（）[E：\ dev \ 4.y \ frameworks \ projects \ framework \ src \ mx \ managers \ PopUpManager.as：193] 在spark.components :: SkinnablePopUpContainer / open（）[E：\ dev \ 4.y \ frameworks \ projects \ spark \ src \ spark \ components \ SkinnablePopUpContainer.as：450] at views :: TodayResults / init（）[C：\ Google Drive \ projects \ android \ ipad \ src \ views \ TodayResults.mxml：27] at views :: TodayResults / ___ TodayResults_View1_creationComplete（）[C：\ Google Drive \ projects \ android \ ipad \ src \ views \ TodayResults.mxml：5] 在flash.events::EventDispatcher/dispatchEventFunction（） at flash.events::EventDispatcher/dispatchEvent(） 在mx.core :: UIComponent / dispatchEvent（）[E：\ dev \ 4.y \ frameworks \ projects \ framework \ src \ mx \ core \ UIComponent.as:13152] 在mx.core :: UIComponent / set initialized（）[E：\ dev \ 4.y \ frameworks \ projects \ framework \ src \ mx \ core \ UIComponent.as:1818] 在mx.managers :: LayoutManager / doPhasedInstantiation（）[E：\ dev \ 4.y \ frameworks \ projects \ framework \ src \ mx \ managers \ LayoutManager.as：842] 在mx.managers :: LayoutManager / doPhasedInstantiationCallback（）[E：\ dev \ 4.y \ frameworks \ projects \ framework \ src \ mx \ managers \ LayoutManager.as：1180]
错误行
loadingScreen = new InitializePopUp();
loadingScreen.open(this,true); <-- error happens here
我正在使用Flex builder 4.6，我正在创建一个flex移动AIR应用程序