Error {code: 500, message: "Unable to generate legends: - breaking Nianwei Liu's TOC

AdrianMarsden

Hi

I am using Nianwei Liu's TOC - however sometimes the expand tree graphic isn't appearing.

I have several dynamic map services and add them all into the TOC.  Mostly this is fine.

However when it fails I get

"Unable to generate legends: zzzzz?Unable to connect to Host: zzzzz Port: -1?Please verify the Service URL specified is correct :- http://zzzzz/arcgis/services/LIVEinternal/aerials/MapServer?"

This happens about 20% of startups.  The Dynamic Service is there and at other times it is fine.

I can see why it breaks the TOC, as without any legends it can't build up the child nodes in functon _createRootLayerNode as there is a IF statement that relies on a renderer being present.

Cheers

ACM

DerekNalder

Hello,

The problem is that the layer is not loaded before the TOC widget is loaded and therefore the TOC.js is hitting the ArcGIS legend service everytime because this.rootLayer.version is not yet populated. This widget will not work with internal only services not accessible to ArcGIS legend service. The proper solution is to check to see if the root layer is loaded before building the legend, if it is not loaded, then add and on("load") to the layer and call the _getLegendInfo. Here's the new code at around line 620 of TOC.js.

         // extenstion point called by framework
         postCreate: function () {
             if ((this.rootLayer instanceof (ArcGISDynamicMapServiceLayer) ||
            this.rootLayer instanceof (ArcGISTiledMapServiceLayer))) {
                 //check if the layer is loaded yet, if not, add a listener to wait
                 if (this.rootLayer.loaded) {
                     if (this._legendResponse) {
                         this._createRootLayerTOC();
                     } else {
                         this._getLegendInfo();
                     }
                 }
                 else {//layer not yet loaded, add listener
                     this.rootLayer.on("load", lang.hitch(this, this._getLegendInfo));
                 }
             } else { //not servicelayer
                 this._createRootLayerTOC();
             }
         },