怎么修改树图标

		<script

 type

="dojo/method" 

data-dojo-event

="getIconStyle" 

data-dojo-args

="item,opened"

>
			if(item && continentStore.getValue(item,"type") == "continent"){
				return {
					backgroundImage: "url('../images/flatScreen.gif')",
					height: "32px",
					width: "32px"
				};
			}else{
				return null;
			}
		</script

>















								//var param = dijit.byId('flowForm').get('value');
								//param.startDate =  dojo.date.stamp.toISOString(param.startDate, {selector: 'date'});
								//param.endDate = dojo.date.stamp.toISOString(param.endDate , {selector: 'date'});