Flex 弹出呼叫框

CallingWindow.mxml

<?xml version="1.0" encoding="utf-8"?>
<s:Group name="MyTitleWindow"
		 xmlns:fx="http://ns.adobe.com/mxml/2009"
		 xmlns:s="library://ns.adobe.com/flex/spark"
		 xmlns:mx="library://ns.adobe.com/flex/halo"
		 width="258" height="90">
	
	<fx:Script>
		<![CDATA[
			import mx.core.IFlexDisplayObject;
			import mx.events.CloseEvent;
			import mx.managers.PopUpManager;
			
			private static var instance:CallingWindow = new CallingWindow;
			private static var _show:Boolean = false;
			
			public static function show():void
			{
				if ( _show ) hide();
				
				PopUpManager.addPopUp(instance, contactsList.app,true);
				PopUpManager.centerPopUp(instance);
				
				_show = true;
			}
			
			public static function hide():void 
			{
				if ( !_show ) return;
				
				PopUpManager.removePopUp(instance);
				_show = false;
			}
			
		]]>
	</fx:Script>
	<s:BorderContainer x="0" y="0" 
					   width="100%" height="90" 
					   backgroundAlpha="0.5" backgroundColor="#AAAAAA" 
					   cornerRadius="12" dropShadowVisible="true">
		<s:Label x="35" y="35" 
				 fontSize="14" fontWeight="bold" 
				 paddingTop="5" text="正在呼叫中"/>
		<s:Button x="164" y="32" 
				  height="25" label="取消呼叫" 
				  chromeColor="#84B4BE"
				  click="{hide()}" cornerRadius="10"/>
		<s:Label id="status" x="107" y="32" 
				 fontSize="14" fontWeight="bold" 
				 paddingTop="5"
				 text="......"/>
	</s:BorderContainer>
</s:Group>

 contactsList.mxml

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" 
			   xmlns:s="library://ns.adobe.com/flex/spark" 
			   xmlns:mx="library://ns.adobe.com/flex/mx" 
			   minWidth="955" minHeight="600"
			   initialize="{app = this;}"
			   >
	<fx:Declarations>
		<!-- Place non-visual elements (e.g., services, value objects) here -->
	</fx:Declarations>
	<fx:Script>
		<![CDATA[
			public static var app:contactsList;
		]]>
	</fx:Script>
	<s:Button x="183" y="227" label="Button" click="{CallingWindow.show()}"/>
</s:Application>