topic Re: identify task being executed in a loop, breaks the dojo deferred addCallback in ArcGIS JavaScript Maps SDK Questions

identify task being executed in a loop, breaks the dojo deferred addCallback

NigelAlford — Fri, 12 Jul 2013 18:10:12 GMT

I'm running a loop based on the currently visible layers to run an identify function for multiple layers simultaneously. The identify task is working but I can't seem to get the deferred portion right. I tried a .then vs addCallback but the return never updates the deferred object that the call is completed. Any insight would be great.

idParams.geometry = evt.mapPoint;    idParams.mapExtent = map.extent;    var feature, lyrIdent = [];    for (var j = 0; j < ident.length; j++) {     if(ident.url != "http://services.arcgisonline.com/ArcGIS/rest/services/Canvas/World_Light_Gray_Reference/MapServer"){      deferred = ident[1].execute(idParams);     }     deferred.then(function(response){      return dojo.map(response, function(response){       var feature = response.feature;       lyrIdent.push(feature.attributes);       var template = new esri.InfoTemplate("#");       feature.setInfoTemplate(template);       return feature;      });     });    }    map.infoWindow.setFeatures([ deferred ]);    map.infoWindow.show(evt.mapPoint);    console.log(lyrIdent); }

Re: identify task being executed in a loop, breaks the dojo deferred addCallback

KenBuja — Mon, 15 Jul 2013 14:44:32 GMT

Take a look at this Fiddle, which returns the results from several different map services.

Re: identify task being executed in a loop, breaks the dojo deferred addCallback

NigelAlford — Mon, 15 Jul 2013 19:09:45 GMT

Thanks Ken. I ended up solving this by creating an object literal, but I'm going to dig through your code, I like your organization and display method on the map.

Re: identify task being executed in a loop, breaks the dojo deferred addCallback

KenBuja — Mon, 15 Jul 2013 19:41:58 GMT

I can't take credit for that example. I came across that posted somewhere on here or GIS.StackExchange and kept it as a bookmark. I'm not sure who coded it.