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javascriptarcgisesriarcgis-js-api

948ESRI Javascript polygon


I am using esri javascript 3.5. I have a list of points that I want to draw it into a polyon. I found this https://developers.arcgis.com/en/javascript/jssamples/util_relation.html but I don't know how to use it. Can I know where I can get a sample? Say I have a array of points...

     dojo.require("esri.map");
  dojo.require("esri.graphic");

  var map ; 
  function init() {
     map = new esri.Map("map",{
      basemap:"topo",
      center:[103.8, 1.35], //long, lat
      zoom:13
    });
                dojo.connect(map,"onLoad", loadData);
  }//end init
  function loadData(){
     var arr =[];
var p = new esri.geometry.Point(103.8, 1.35);
arr.push(p);
p = new esri.geometry.Point(103.8, 1.35222);
arr.push(p);
var polySymbolRed = new esri.symbol.SimpleFillSymbol(
                esri.symbol.SimpleLineSymbol.STYLE_SOLID,
                new esri.symbol.SimpleLineSymbol(esri.symbol.SimpleLineSymbol.STYLE_SOLID,
                new dojo.Color([0, 0, 0, 1]), 1),
                new dojo.Color([255, 0, 0, 0.2])
        );

var gra = new esri.Graphic(arr,polySymbolRed);
map.graphics.add(gra);


  }

Solution

  • You're very close, you just need to massage that array a bit before creating the .Graphic:

    var poly = new esri.geometry.Polygon({
                    "spatialReference": {" wkid":4326 },
                    "fields": [{
                        "name": "FID",
                        "type": "esriFieldTypeOID",
                        "alias": "FID",
                        "domain": null          
                    },...]
                });
    var ring = new Array();
    
    //push points into array
    
    poly.addRing(ring);
    
    var gra = new esri.Graphic(poly,polySymbolRed);
    //Maybe:
    //var gra = new esri.Graphic(esri.geometry.geographicToWebMercator(poly),polySymbolRed);
    //depending on what SR your map is using...