ArcGIS API for Flex(四) 地图的当前范围和规模

通过导航地图（平移/缩放）改变程度，或使用导航滑块来放大/缩小。并且显示地理坐标

效果如下：

代码：（主要是esri官方代码，稍作修改）

<?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:esri="http://www.esri.com/2008/ags"
			   pageTitle="Map Extent and Mouse Coordinates">
	
	<fx:Script>
		<![CDATA[
			import com.esri.ags.geometry.Extent;
			import com.esri.ags.geometry.MapPoint;
			import com.esri.ags.utils.WebMercatorUtil;
			
			// when mouse (cursor) is on the map ...
			private function loadHandler():void
			{
				myMap.addEventListener(MouseEvent.MOUSE_MOVE,mouseMoveHandler);
			}
			
			// ... show coordinates of current (mouse) location
			private function mouseMoveHandler(event:MouseEvent):void
			{
				const mapPoint:MapPoint = myMap.toMapFromStage(event.stageX,event.stageY);
				const latlong:MapPoint = WebMercatorUtil.webMercatorToGeographic(mapPoint) as MapPoint;
				mousecoords.text =
					"x,y is " + mapPoint.x.toFixed(0) + "," + mapPoint.y.toFixed(0)
					+ " and Lat/Long is: " + latlong.y.toFixed(6)
					+ " / " + latlong.x.toFixed(6);
			}
			
			// convert current projected extent to geographic and show as such
			protected function showExtentInGeographic(extent:Extent):String
			{
				const geoExtent:Extent = WebMercatorUtil.webMercatorToGeographic(myMap.extent) as Extent;
				// return geoExtent.toString() + ".." ;
				return " " + geoExtent.xmin.toFixed(6)
					+ "," + geoExtent.ymin.toFixed(6)
					+ "," + geoExtent.xmax.toFixed(6)
					+ "," + geoExtent.ymax.toFixed(6)
					+ "   (wkid: " + geoExtent.spatialReference.wkid + ")";
			}
		]]>
	</fx:Script>
	
	<s:controlBarLayout>
		<s:VerticalLayout gap="10"
						  paddingBottom="7"
						  paddingLeft="10"
						  paddingRight="10"
						  paddingTop="7"/>
	</s:controlBarLayout>
	<s:controlBarContent>
		<s:RichText width="100%" fontFamily="宋体" fontSize="16" fontWeight="bold" color="#006030">
			此示例演示如何使用的事件监听器
			鼠标以显示鼠标所在位置的最新信息。
			地图的当前范围和规模也显示为你
			通过导航地图（平移/缩放）改变程度，或使用
			导航滑块来放大/缩小。 
		</s:RichText>
		<s:HGroup>
			<s:Label fontWeight="bold" text="当前地图范围:" fontFamily="宋体" fontSize="16" color="#006030"/>
			<s:RichEditableText editable="false" text='xmin="{myMap.extent.xmin.toFixed(0)}" ymin="{myMap.extent.ymin.toFixed(0)}" xmax="{myMap.extent.xmax.toFixed(0)}" ymax="{myMap.extent.ymax.toFixed(0)}"   (wkid="{myMap.spatialReference.wkid}")' fontFamily="宋体" fontSize="16" fontWeight="bold" color="#006030"/>
		</s:HGroup>
		<s:HGroup>
			<s:Label  text=" 当前地图范围（地理）:" fontFamily="宋体" fontSize="16" fontWeight="bold" color="#006030"/>
			<s:RichEditableText editable="false" text="{showExtentInGeographic(myMap.extent)}" fontFamily="宋体" fontSize="16" fontWeight="bold" color="#006030"/>
		</s:HGroup>
		<s:HGroup>
			<s:Label fontFamily="宋体" fontSize="16" fontWeight="bold" color="#006030" text="目前的鼠标坐标:"/>
			<s:RichEditableText id="mousecoords"
								editable="false"
								text="将鼠标移动到地图上看到它的当前坐标..." fontFamily="宋体" fontSize="16" fontWeight="bold" color="#006030"/>
		</s:HGroup>
		<s:HGroup>
			<s:Label fontFamily="宋体" fontSize="16" fontWeight="bold" color="#006030" text=" 当前地图的比例尺是："/>
			<s:RichEditableText editable="false" text="1:{myMap.scale.toFixed(0)} (level {myMap.level})" fontFamily="宋体" fontSize="16" fontWeight="bold" color="#006030"/>
		</s:HGroup>
	</s:controlBarContent>
	
	<esri:Map id="myMap" load="loadHandler()">
		<esri:extent>
			<esri:Extent xmin="3035000" ymin="4305000" xmax="3475000" ymax="10125000">
				<esri:SpatialReference wkid="102100"/>
				<!-- same as tiled map service below -->
			</esri:Extent>
		</esri:extent>
		<esri:ArcGISTiledMapServiceLayer url="http://server.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer"/>
	</esri:Map>
	
</s:Application>