How to identify multiple layers from 3 services when visible?

Discussion created by mcdade31 on Jan 25, 2013
Latest reply on Jan 29, 2013 by Arkitech
I have three services that I need to be identified, only when the layers are visible. Currently my code references 1 service. I have followed the steps outlined in this thread (I think), however, the app still identifies if a layer is turned off in the TOC. Link to my App.

I have also attempted to implement the code sample found here, without any luck.

I guess my question/issue is two pronged to try and get maximum understanding of the processes:
1. How can I make my code ID layers only when visible?
2. How can I add the additional services to my code and ID all three services only when visible?

My current code is:
dojo.require("esri.dijit.Popup"); //Infowindow
var identifyTask,identifyParams; 

function mapReady(map){

    //create identify tasks and setup parameters 
       identifyTask = new esri.tasks.IdentifyTask("");
       identifyParams = new esri.tasks.IdentifyParameters();
       identifyParams.tolerance = 3;
       identifyParams.returnGeometry = true;
     //Choose which layers in the array you would like to be ID'd in the popup  
    identifyParams.layerIds = [0,1,2,3,4];
       identifyParams.layerOption = esri.tasks.IdentifyParameters.LAYER_OPTION_VISIBLE;
       identifyParams.width  = map.width;
       identifyParams.height = map.height;
   function executeIdentifyTask(evt) {
        identifyParams.geometry = evt.mapPoint;
        identifyParams.mapExtent = map.extent;
    identifyParams.layerIds = visible
        var deferred = identifyTask.execute(identifyParams);

        deferred.addCallback(function(response) {     
          // response is an array of identify result objects    
          // Let's return an array of features.
          return, function(result) {
            var feature = result.feature;
            feature.attributes.layerName = result.layerName;
            if(result.layerName === 'Zoning Classifications'){
              var template = new esri.dijit.PopupTemplate({
       description:"<b>Zoning:</b> {Zoning Classification} <br/> <b>Description:</b> {Zoning Description}"
            else if (result.layerName === 'Assisted Living Facilities'){
              var template = new esri.dijit.PopupTemplate({
       title:"Assisted Living Facilities",
       description:"<b>Parcel ID:</b> {Parcel} <br/> <b>Applicant:</b> {BusinessApplicantName} <br/> <b>No. of Residents</b> {NbrResidents}"
      else if (result.layerName === 'Family Divisions'){
              var template = new esri.dijit.PopupTemplate({
       title:"Family Divisions",
       description:"<b>Parcel ID:</b> {Parcel} <br/> <b>Project Number:</b> {project_nbr} </br> <b>Status:</b> {Status}"
      else if (result.layerName === 'Policy 120'){
              var template = new esri.dijit.PopupTemplate({
       title:"Policy 120",
       description:"<b>Parcel ID:</b> {Parcel} <br/> <b>Business Name:</b> {BusinessName} </br> <b>Date of Letter:</b> {DateOfLetter}"
      else if (result.layerName === 'Zoning Changes'){
              var template = new esri.dijit.PopupTemplate({
       title:"Zoning Changes",
       description:"<b>Parcel ID:</b> {Parcel} <br/> <b>Request Number:</b> {REQUEST_NBR} </br> <b>Property Owner:</b> {PROPERTY_OWNER}"
            return feature;

        // InfoWindow expects an array of features from each deferred
        // object that you pass. If the response from the task execution 
        // above is not an array of features, then you need to add a callback
        // like the one above to post-process the response and return an
        // array of features.
        map.infoWindow.setFeatures([ deferred ]);;