Cascading nested filtering

[FaryalSafdar]

i have selected feature(feature layer) from combobox and it zoom to the feature . now i want to clear combobox slection and map . and zoom map to its default zoom.

here is my code

function clearall()

{

//combobox selection clear    dijit.byId("A1").reset();    dijit.byId("A2").reset();    dijit.byId("A3").reset();    dijit.byId("A4").reset();    dijit.byId("A5").reset();     //layer selection clear     document.getElementById('A1_layer').clearSelection();      document.getElementById('A2_layerC').clearSelection();      document.getElementById('A3_layerC').clearSelection();      document.getElementById('A4_layerC').clearSelection();      document.getElementById('A5_layerC').clearSelection(); } //cascading code app = {    zoomRow: function(id, which){       var query = new Query();      //var thePoly, theExtent;      if(which == "Land"){        query.where = "Name='" + (id).toString() + "'";        console.info(query.where);        query.returnGeometry = true;        A1_layer.selectFeatures(query, FeatureLayer.SELECTION_NEW, function (features) {          thePoly = features[0].geometry;          theExtent = thePoly.getExtent().expand(2); //Zoom out slightly from the polygon's extent          map.setExtent(theExtent);        });        esriRequest({          url: "http://localhost:6080/arcgis/rest/services/........",          content:{            f:'json'          },          handleAs:'json',          callbackParamName:'callback',          timeout:15000        }).then(lang.hitch(this,function(response){          var store2 = new Memory({data:[]});          dijit.byId("A2").set('store',store2);          var data = array.map(response.features,lang.hitch(this,function(feat, index){            var name = feat.attributes.nam;            var dataItem = {              id:index,              name:name             };            return dataItem;          }));          store2 = new Memory({data:data});          dijit.byId("A2").set('store',store2);          document.getElementById('A2').value = "Select Room";        }));      }
// combobox<input id="A1" data-dojo-type="dijit/form/ComboBox" value="Select landing" onchange="app.zoomRow(document.getElementById('A1').value, 'Land');" data-dojo-props="maxHeight: 200" style="overflow:auto; width:200px; background-color: #E7FCCA "/ ><br></br>  <input id="A2" data-dojo-type="dijit/form/ComboBox" value="Select room onchange="app.zoomRow(document.getElementById('A2').value, 'Room');"style="overflow:auto; width:200px ;background-color: #E7FCCA" /> <br></br>

but i got error "Cannot read property 'geometry' of undefined" at thePoly = features[0].geometry;

[RobertScheitlin__GISP · Accepted solution]

Faryal,

   So you should just simply check for a null in an if block before proceeding:

        A1_layer.selectFeatures(query, FeatureLayer.SELECTION_NEW, function (features) {
          if(features[0]){
            thePoly = features[0].geometry;
            theExtent = thePoly.getExtent().expand(2);
            //Zoom out slightly from the polygon's extent
            map.setExtent(theExtent);
          }
        });‍‍‍‍‍‍‍‍

[FaryalSafdar]

thanks for your reply but as i mentioned it is cascading filtering. if i use if condition it does not zoom to the next feature in the combobox.

[RobertScheitlin__GISP]

Faryal,

  So you allow then to select a room before they select a landing? Why would selecting a landing not return any geometry results?