topic Re: select points in a graphic when there is a time slider in ArcGIS JavaScript Maps SDK Questions

select points in a graphic when there is a time slider

AngieGreig — Wed, 08 Jun 2011 20:58:57 GMT

My code allows a user to draw a polygon to select some points. Initially everything works fine. However if I move the time slider to a different year and draw a polygon only some or none of the enclosed points are selected. Here is some of the relevant code.
Thanks.

      function initToolbar(map) {
        tb = new esri.toolbars.Draw(globals.map);
        dojo.connect(tb, "onDrawEnd", addGraphic);
      }

      function addGraphic(poly) {
        var symbol = tb.fillSymbol;
        globals.map.graphics.add(new esri.Graphic(poly, symbol));

        var queryTask = new esri.tasks.QueryTask("http://..../MapServer/0");
        var query = new esri.tasks.Query();
        query.where = "SPECIES_CODE = " + globals.speciesID +" and YEAR = " + globals.year;
        query.outSpatialReference = {wkid:102100};
        query.timeExtent = globals.map.timeExtent;
        query.returnGeometry = true;
        query.outFields = ["YEAR","SPECIES_CODE"];
        queryTask.execute(query, addPointsToMap);
      }

      //add points to map and set their symbology
      function addPointsToMap(featureSet) {
        var i = globals.map.graphics.graphics.length - 1;
        dojo.forEach(featureSet.features,function(feature){
          if (globals.map.graphics.graphics.geometry.contains(feature.geometry)) {
            globals.map.graphics.add(feature.setSymbol(new esri.symbol.SimpleMarkerSymbol().setColor(new dojo.Color([255,0,0]))));
          }
        });
     }

      function timeSliderChanged(timeExtent)
      {
         globals.year = timeExtent.endTime.getUTCFullYear();
         globals.map.graphics.clear()
         showMapInfo();
      }

Re: select points in a graphic when there is a time slider

StephenLead — Wed, 08 Jun 2011 23:27:27 GMT

Hi Angie,

        query.where = "SPECIES_CODE = " + globals.speciesID +" and YEAR = " + globals.year;
        query.timeExtent = globals.map.timeExtent;

      function timeSliderChanged(timeExtent)
      {
         globals.year = timeExtent.endTime.getUTCFullYear();
      }

Are you sure you need to store the year in a variable, and use this in the query.where statement? If the layer is time-aware, then the query's time extent (query.timeExtent = map.timeExtent) should take care of this for you.

Can you put a break-point inside the timeSliderChanged function, and verify that globals.year is being set correctly? They put another break-point inside the query and ensure that query.where is correct?

This may help you to debug what's going wrong.

Steve

Re: select points in a graphic when there is a time slider

AngieGreig — Thu, 09 Jun 2011 16:42:33 GMT

Steve,
Thanks you put me on the right track. I had been convinced that the problem was with geometry.contains statement whereas the query return was faulty. The query itself was fine. The solution lay in changing a parameter during the service creation. I increased the limit on the number of records returned and problem solved.
Thanks for your help,
agreig