Alert,TitleWindow以及PopUp的简单分析

这两天为了Fluorida的closePopUp功能，读了点Flex框架的源码，对Alert，TitleWindow以及Flex的PopUp功能做了简单的分析。
【Alert和PopUp】
Alert内部其实是调用了PopUpManager.在parent参数为null或者为Application的时候，弹出的窗口将跟当前Application在一个容器下。Alert在最顶层，Application在最底层，中间那层是一个称之为modalWindows的控件，其实就是Alert后面那个磨砂的层。为了点到Alert上的按钮，写了一个小程序分析Alert的结构，不是很好读，但是可以运行一下，看看分析出的Alert的内部结构：（大略说一下，Alert的Child有一个AlertForm，而AlertForm的Child除了第一个是TextField以外，都是按钮）

<!----> <? xml version="1.0" encoding="utf-8" ?>
< mx:Application  xmlns:mx ="http://www.adobe.com/2006/mxml"  layout ="horizontal" >
     < mx:Script >
         <![CDATA[
            import mx.core.IChildList;
            import mx.core.UIComponent;
            import mx.core.IFlexDisplayObject;
            import mx.managers.ISystemManager;
            import mx.managers.PopUpManagerChildList;
            import mx.managers.PopUpManager;
            import mx.controls.Alert;
            import mx.events.CloseEvent;
            import mx.core.Singleton;
            import mx.managers.IPopUpManager;
            
            private function showSimpleAlert():void{
                Alert.okLabel="oKey";
                Alert.show("Hello, World!","",15,null,alertCloseHandle);
                var myTimer:Timer = new Timer(1000, 1);
                   myTimer.addEventListener("timer", timerHandler);
                   myTimer.start();            
            }
            
            private function alertCloseHandle(event:CloseEvent):void{
                simpleAlertShower.label = event.detail.toString();
            }
            
            private function timerHandler(event:TimerEvent):void{
                var text:String = "elements:";
                var sm:ISystemManager = (Application.application.root as ISystemManager);
                text+=sm.numChildren.toString();
                text+=";\n modalWindows:";
                text+=sm.numModalWindows.toString();
                for(var index:int = 0; index < sm.numChildren; index++)
                {
                    text += "\n" + index + " : ";
                    text += sm.getChildAt(index).toString(); 
                }
                
                var alert:Alert = sm.getChildAt(sm.numChildren - 1) as Alert;
                text += "\n buttonFlags : "+alert.buttonFlags;
                text += "\n alertChildren:" + alert.numChildren;
                for(var index:int = 0; index < alert.numChildren; index++)
                {
                    text +="\n" + alert.getChildAt(index).toString();
                }
                var alertForm:UIComponent = alert.getChildAt(0) as UIComponent;
                text += "\n alertFormChildren:" + alertForm.numChildren;
                
                for(var index:int = 0; index < alertForm.numChildren; index++)
                {
                    text +="\n"+index+":"+ alertForm.getChildAt(index).toString();
                    
                }
                popupChildText.text = text;
                alertForm.getChildAt(1).dispatchEvent(new MouseEvent(MouseEvent.CLICK));
//                var popupContainer:IChildList = (application.root as IChildList);
//                PopUpManager.removePopUp(popupContainer.getChildAt( popupContainer.numChildren - 1 ) as IFlexDisplayObject);

            }
         ]]>
     </ mx:Script >     
       < mx:Button  id ="simpleAlertShower"  click ="showSimpleAlert();"  label ="Click Me" />
       < mx:Text  id ="popupChildText" />
    
</ mx:Application >

【关于TitleWindow】
TitleWindow作为弹出窗口的时候，跟Alert处的位置没什么区别，我想说的是TitleWindow的closeButton在哪里。下面这个同样不好读的程序可以帮助你分析TitleWindow或者说Panel里面都有用什么，以及closeButton在哪，其实就是在rawChildren的最后一个。

<!----> <? xml version="1.0" encoding="utf-8" ?>
< mx:Application  xmlns:mx ="http://www.adobe.com/2006/mxml"  layout ="horizontal" >
     < mx:Script >
         <![CDATA[
            import mx.containers.TitleWindow;
            import mx.core.IChildList;
            import mx.core.UIComponent;
            import mx.core.IFlexDisplayObject;
            import mx.managers.ISystemManager;
            import mx.managers.PopUpManagerChildList;
            import mx.managers.PopUpManager;
            import mx.controls.Alert;
            import mx.events.CloseEvent;
            import mx.core.Singleton;
            import mx.managers.IPopUpManager;
            
            private function showSimpleAlert():void{
                var popUpWindow:TitleWindow = TitleWindow(PopUpManager.createPopUp(this,TitleWindow,true));
                popUpWindow.width = 400;
                popUpWindow.height = 300;
                popUpWindow.visible = true;
                popUpWindow.showCloseButton = true;
                var myTimer:Timer = new Timer(2000, 1);
                   myTimer.addEventListener("timer", timerHandler);
                   myTimer.start();    
            }
            
            private function alertCloseHandle(event:CloseEvent):void{
                simpleAlertShower.label = event.detail.toString();
            }
            
            private function timerHandler(event:TimerEvent):void{
                var text:String = "elements:";
                var sm:ISystemManager = (Application.application.root as ISystemManager);
                text+=sm.numChildren.toString();
                text+=";\n modalWindows:";
                text+=sm.numModalWindows.toString();
                text+="\n top children: ";
                for(var index:int = 0; index < sm.numChildren; index++)
                {
                    text += "\n" + index + " : ";
                    text += sm.getChildAt(index).toString(); 
                }
                
                var titleWindow:TitleWindow = sm.getChildAt(sm.numChildren - 1) as TitleWindow;
                text += "\n popUpWindowrawChildren:" + titleWindow.rawChildren.numChildren;
                for(var index:int = 0; index < titleWindow.rawChildren.numChildren; index++)
                {
                    text +="\n" + titleWindow.rawChildren.getChildAt(index).toString();
                }
                var titleBar:UIComponent = (titleWindow.rawChildren.getChildAt(2) as UIComponent);
                text += " has " + titleBar.numChildren;
                text += "\n" + titleBar.getChildAt(3).toString();
                
                popupChildText.text = text;
//                var popupContainer:IChildList = (application.root as IChildList);
//                PopUpManager.removePopUp(popupContainer.getChildAt( popupContainer.numChildren - 1 ) as IFlexDisplayObject);
                PopUpManager.removePopUp(titleWindow);
            }
         ]]>
     </ mx:Script >     
       < mx:Button  id ="simpleAlertShower"  click ="showSimpleAlert();"  label ="Click Me" />
       < mx:Text  id ="popupChildText" />
    
</ mx:Application >