topic Re: Symbol not showing in correct place in ArcGIS API for Flex Questions

Symbol not showing in correct place

PhilipTownsend — Mon, 22 Oct 2012 14:21:51 GMT

I need to place a symbol on a map at a specified Lat/Lon coordinate. For testing purposes, I am executing my method from a mouse click anywhere on the map. I have hard coded the coordinate values and am using the following spatial reference

<esri:SpatialReference id="wgs" wkid="4326"/>

When the method is executed, the symbol appears at 0,0 on the map and seems to disregard the coordinates passed in. My GraphicsLayer is grLayer. What am I doing wrong? Thanks!

   private function onMapClick(event:MapMouseEvent):void{
    var coordstring:String = "38.0594, 81.1121";
    var coords:Array = coordstring.split(",");
    var g:Graphic = new Graphic(new MapPoint(coords[0],coords[1],wgs));
    grLayer.add(g);
    //Alert.show("Mouse clicked at: " + event.mapPoint.x + "|" + event.mapPoint.y);
   }

Re: Symbol not showing in correct place

KenBuja — Mon, 22 Oct 2012 14:47:11 GMT

What projection is your application? If it's in Web Mercator, you'll have to project that point to that projection, like in the following:

private function onMapClick(event:MapMouseEvent):void{      var coordstring:String = "38.0594, 81.1121";      var coords:Array = coordstring.split(",");      var mappoint1:MapPoint = new MapPoint(coords[0],coords[1],wgs);      var mappoint2:Geometry = WebMercatorUtil.geographicToWebMercator(mappoint1);       var g:Graphic = new Graphic();      g.geometry = mappoint2;          grLayer.add(g); }

Re: Symbol not showing in correct place

RobertScheitlin__GISP — Sat, 11 Dec 2021 21:43:37 GMT

Philip,

If your maps WKID is in webmercator than use the new WebMercatorMapPoint instead:

private function onMapClick(event:MapMouseEvent):void{
    var coordstring:String = "38.0594, 81.1121";
    var coords:Array = coordstring.split(",");
    var g:Graphic = new Graphic(new WebMercatorMapPoint(coords[0],coords[1]));
    grLayer.add(g);
    //Alert.show("Mouse clicked at: " + event.mapPoint.x + "|" + event.mapPoint.y);
}

If your maps WKID (Spatial reference) is something else than you need to re-project the coordinates to that WKID:

See this sample: http://resources.arcgis.com/en/help/flex-api/samples/01nq/01nq0000004w000000.htm

Don't forget to click the Mark as answer check on this post and to click the top arrow (promote).
Follow these steps as shown in the below graphic:

Re: Symbol not showing in correct place

DasaPaddock — Mon, 22 Oct 2012 17:48:01 GMT

You could also just use the WebMercatorMapPoint:
http://resources.arcgis.com/en/help/flex-api/apiref/com/esri/ags/geometry/WebMercatorMapPoint.html