ArcGIS For Flex学习之Mapping---Map Extent and Mouse Coordinates

<?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%">
This sample demonstrates how to use event listeners on the
mouse to display current information about the mouse location.
The map's current extent and scale is also displayed as you
change the extent by navigating the map (pan/zoom) or use the
navigation slider to zoom in/out.
</s:RichText>
<s:HGroup>
<s:Label fontWeight="bold" text="Current map extent:"/>
<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}")'/>
</s:HGroup>
<s:HGroup>
<s:Label fontWeight="bold" text="Current map extent (in geographic):"/>
<s:RichEditableText editable="false" text="{showExtentInGeographic(myMap.extent)}"/>
</s:HGroup>
<s:HGroup>
<s:Label fontWeight="bold" text="Current Mouse Coordinates:"/>
<s:RichEditableText id="mousecoords"
editable="false"
text="Move the mouse over the map to see its current coordinates..."/>
</s:HGroup>
<s:HGroup>
<s:Label fontWeight="bold" text="Current map scale is"/>
<s:RichEditableText editable="false" text="1:{myMap.scale.toFixed(0)} (level {myMap.level})"/>
</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>