topic Re: Set initial extent of map with FeatureLayer in ArcGIS JavaScript Maps SDK Questions

Set initial extent of map with FeatureLayer

RobertoOliveira — Sun, 12 Dec 2021 04:07:58 GMT

Trying to set the initial extent of map with same extent of a existing Feature Layer.

Code:

var featureLayer = new FeatureLayer("http://server/arcgis/rest/services/MyService/0", {
  mode: FeatureLayer.MODE_ONDEMAND,
  outFields: ["*"]
});

featureLayer.on("load", function(e) {
  var initialExtent = featureLayer.fullExtent;

  map = new Map('map-view', {
    basemap: "streets",
    extent: initialExtent
  });
}

This don't work, and I have the following error on console:

Map: Geometry (wkid: 31982) cannot be converted to spatial reference of the map (wkid: 102100)

The Feature Layer was using the Spatial Reference wkid 31982.

Why the map have the Spatial Reference wkid 102100?

This is the only feature layer existing on code, and I "loaded" the Feature Layer before initialize the map, so, until I initialize the map, map = null

What I need to do for the map start up with the same extent of the feature layer?

Re: Set initial extent of map with FeatureLayer

KenBuja — Thu, 14 Apr 2016 14:18:05 GMT

You can use a GeometryService to project the extent of your service into the Web Mercator projection of the map.

Re: Set initial extent of map with FeatureLayer

RobertoOliveira — Sun, 12 Dec 2021 04:08:01 GMT

Thanks Ken Buja

I have made the following code if anybody need (can be optimized):

// Geometry Service
var gs = new GeometryService("https://server/arcgis/rest/services/Utilities/Geometry/GeometryServer");


// wkid of map and feature layer
var map_wkid = map.extent.spatialReference.wkid;
var feature_wkid = featureLayer.fullExtent.spatialReference.wkid;


// if wkid of map and feature layer is different, project
if (map_wkid != feature_wkid) {

  // get the map spatialReference
  var sr = new SpatialReference(map_wkid);

  // project
  var project = gs.project([featureLayer.fullExtent], sr);


  // anonymous functions (success and error)
  // success
  project.then(function(result) {
    // if a map exist, destroy first
    if (map) {
      map.destroy();


      // create a new map with extent of feature layer
      map = new Map("map-view", {
        extent: result[0],
        basemap: "topo",
      });
     
      // add the feature layer
      map.addLayers([featureLayer]);
    }


  // error
  }, function(err) {
    console.log('error');
    console.log(err);
  });
}