topic TypeError: clazz is not a constructor in ArcGIS Web AppBuilder Questions

TypeError: clazz is not a constructor

NadirHussain — Mon, 11 Feb 2019 13:42:17 GMT

i have two user defined functions.When i declare and call them i get this error.i dont know why it is happening .please help or suggest me how to declare function inside a web app builder widget. Thanks.

startup: function() {
this.inherited(arguments);
var panel = this.getPanel();
panel.position.width = 260;
panel.position.height = 300;
panel.setPosition(panel.position);
panel.panelManager.normalizePanel(panel);

this.FieldsCombo.watch('displayedValue', lang.hitch(this, function(property, oldValue, newValue) {
alert(oldValue+"_________"+newValue);
this.getDistinctValues("https://localhost:6443/arcgis/rest/services/BaseMap/MapServer/"+_strSourceLayer,newValue);---------------------->Error on this line
}));
},
getDistinctValues: function (strURL,strFieldName){
this.getFeatuers(strURL,"1=1", [strFieldName],function(_target){------> Error on this line
for(var i = 0; i < _target.features.length; i++){
var feat=_target.features;
alert(feat[strFieldName]);
}
});
},
getFeatuers: function (URL,where,OUTFields,callback ){
var query = new _Query();
var queryTask = new _QueryTask( URL);
query.where = where;
query.outSpatialReference = _map.spatialReference;
query.returnGeometry = true;
query.outFields = OUTFields;
queryTask.execute(query, callback);
},

});
return clazz;

});

Re: TypeError: clazz is not a constructor

RobertScheitlin__GISP — Sat, 11 Dec 2021 07:56:51 GMT

Nadir,

Your biggest problem is non standard widget coding practices. You are coding based on standard JS coding practices. When developing widgets/dijits there are several changes you need to make coding practices.

When calling this.getDistinctValues

      onOpen: function() {
        console.log('onOpen');
      },

      onClose: function() {
        console.log('onClose');
      },

      getDistinctValues: function (strURL,strFieldName){
        this.getFeatuers(strURL, "1=1", [strFieldName], lang.hitch(this, function(_target){
          for(var i = 0; i < _target.features.length; i++){
            var feat=_target.features[i];
            alert(feat[strFieldName]);
          }
        }));
      },

      getFeatuers: function (URL, where, OUTFields, callback){
        var query = new _Query();
        var queryTask = new _QueryTask( URL);
        query.where = where;
        query.outSpatialReference = _map.spatialReference; 
        query.returnGeometry = true;
        query.outFields = OUTFields;
        queryTask.execute(query, lang.hitch(this, callback));
      }

    });
  });‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

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