FLEX4 List代码触发选择

在Flex4中需要触发list的选择事件，代码如下:

	<s:List id="groupContainer" width="160" height="100%" itemRenderer="components.group.GroupItemRenderer" 
			dataProvider="{Managers.getGroupManager().groups}" change="groupItemChange(event)" alpha="0.9" >
	</s:List>

			private function initUI():void {
				groupContainer.selectedIndex = 0;
				var event:IndexChangeEvent = new IndexChangeEvent(IndexChangeEvent.CHANGE,false,-1,0);
				groupContainer.dispatchEvent(event);
				//
				Managers.getPacketManager().addListener(onGroupCallResponse,new PacketFilterType(PacketType.GROUP_CALL));
			}