topic Re: queryTask.execute Fails in ArcGIS JavaScript Maps SDK Questions

queryTask.execute Fails

JamesCrandall — Sun, 12 Dec 2021 01:27:12 GMT

I'm getting a ReferenceError "results is not defined" on the queryTask.execute:

   //first, check to see if a workplan boundary exists            
    if (this.workplanId) {
     var queryUrl = "https://somewebsite/someagssite/rest/services/folder/servicename/FeatureServer/0"            
     var queryTask = new QueryTask(queryUrl);
     var query = new Query();
     query.returnGeometry = true;
     query.where = "workplanId ='" + this.workplanId + "'";

     debugger;
     queryTask.execute(query).then(function (results) {
         this.workplanCheckValue = results.features.length;                        
     });
    }

    console.log("workplanCheck value is: ", this.workplanCheckValue)‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

I need to set this.workplanCheckValue to the number of features returned from the queryTask.

Any assistance appreciated!

Re: queryTask.execute Fails

RobertScheitlin__GISP — Fri, 27 Apr 2018 16:23:13 GMT

James,

Looks like a scope issue again. When you are inside a function that does not use lang.hitch or a closure then "this" has a different scope then outside the function.

Re: queryTask.execute Fails

JamesCrandall — Sun, 12 Dec 2021 01:27:14 GMT

I'm struggling on this whole concept for some reason. It's just not registering how to apply and where -- my failed attempt:

queryTask.execute(query).then(lang.hitch(function (result) {
                    this.workplanCheckValue = result.features.length;
                }));
               ‍‍‍‍

Re: queryTask.execute Fails

RobertScheitlin__GISP — Sun, 12 Dec 2021 01:27:17 GMT

James,

OK maybe I can help explain. Anytime you have some code that has a function that returns something that means it returns a different scope and thus has to be hitched to the current scope.

                queryTask.execute(query).then(lang.hitch(this, function (result) {
                    this.workplanCheckValue = result.features.length;
                }));‍‍‍

Your where missing the "this" that you were wanting to hitch to.

Re: queryTask.execute Fails

JamesCrandall — Sun, 12 Dec 2021 01:27:21 GMT

Now it leads me to a "TypeError: g.join is not a function"? Something new. <-- this appears to be because my query.outFields not correctly set as an array.

However, I'm still getting the same error on my original code:

////first, check to see if a workplan boundary exists            
            if (this.workplanId) {
                var queryUrl = "https://somesite/rest/services/myservice/FeatureServer/0";
                var queryTask = new QueryTask(queryUrl);
                var query = new Query();
                query.returnGeometry = true;
                query.outFields = ['*']
                query.where = "workplanId ='" + this.workplanId + "'";
                debugger;
                queryTask.execute(query).then(lang.hitch(this, function (result) {
                    debugger;
                    this.workplanCheckValue = result.features.length;
                    console.log("workplanCheck value is: ", this.workplanCheckValue)
                }));
               
            }
                      
            console.log("workplanCheck value is: ", this.workplanCheckValue)‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

Thanks again for your explanation!

Re: queryTask.execute Fails

RobertScheitlin__GISP — Fri, 27 Apr 2018 16:54:01 GMT

Is that error coming from the function above?...

Re: queryTask.execute Fails

JamesCrandall — Fri, 27 Apr 2018 16:54:54 GMT

Sorry -- I was too slow. I updated my last reply. That other error was due to

query.outFields = ['*']

Re: queryTask.execute Fails

JamesCrandall — Fri, 27 Apr 2018 16:59:52 GMT

This is what I see on result when in debug:

Re: queryTask.execute Fails

RobertScheitlin__GISP — Sun, 12 Dec 2021 01:27:23 GMT

James,

I tend to do my queries like this:

////first, check to see if a workplan boundary exists            
            if (this.workplanId) {
                var queryUrl = "https://somesite/rest/services/myservice/FeatureServer/0";
                var queryTask = new QueryTask(queryUrl);
                var query = new Query();
                query.returnGeometry = true;
                query.outFields = ['*']
                query.where = "workplanId ='" + this.workplanId + "'";
                debugger;
                queryTask.execute(query, lang.hitch(this, function (result) {
                    debugger;
                    this.workplanCheckValue = result.features.length;
                    console.log("workplanCheck value is: ", this.workplanCheckValue)
                }));
            }
                      
            console.log("workplanCheck value is: ", this.workplanCheckValue)‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

Re: queryTask.execute Fails

JamesCrandall — Fri, 27 Apr 2018 18:11:47 GMT

Oh actually, that does work. My fault (again).

Re: queryTask.execute Fails

RobertScheitlin__GISP — Fri, 27 Apr 2018 18:17:32 GMT

James,

It is likely something simple But I do not see it in the code you are sharing. You do not see any errors in the console when you try and run the code, beside the reference error?

Re: queryTask.execute Fails

JamesCrandall — Fri, 27 Apr 2018 18:21:03 GMT

Sorry, that was my fault again. I was stepping thru the debugger. Your code works perfectly of course!

Thanks again for your assist and lesson.

Re: queryTask.execute Fails

JamesCrandall — Sun, 12 Dec 2021 01:27:26 GMT

The reason why I thought it wasn't properly set is because I have this queryTask in the Startup: function() and it seems to not fire (deferred?) in the order I am expected. That is it will initially hit eh queryTask but then not actually execute and simply continue on thru until the startup finished then it will .exectute. For example, the first console print is:

console.log("2 workplanCheck value is: ", this.workplanCheckValue)

Then this:

console.log("1 workplanCheck value is: ", this.workplanCheckValue)

So what happens is my condition statements get evaluated first before I can set the this.workplanCheckValue variable to the result of the queryTask.

 constructor: function (args) {
    lang.mixin(this, args);
    window.map = this.map;

        },

 startup: function () {
    ////first, check to see if a workplan boundary exists
    if (this.workplanId) {
     var queryUrl = "https://somesite/rest/services/myservice/FeatureServer/0";
     var queryTask = new QueryTask(queryUrl);
     var query = new Query();
     query.returnGeometry = true;
     query.outFields = ['*']
     query.where = "workplanId ='" + this.workplanId + "'";
     debugger;
     queryTask.execute(query, lang.hitch(this, function (result) {
         debugger;
         this.workplanCheckValue = result.features.length;
         console.log("1 workplanCheck value is: ", this.workplanCheckValue)
     }));
    }

    console.log("2 workplanCheck value is: ", this.workplanCheckValue)
    //debugger;
    if (this.editLayer == 'WP' && this.reviewStatus == 'Draft Mode' && this.workplanCheckValue > 0 ) {
     this.beginWork_Workplan_ExistingBoundary();
    }
    else if (this.editLayer == 'WP' && this.reviewStatus == 'Draft Mode' && this.workplanCheckValue < 1) {
     this.beginWork_Workplan_NoExistingBoundary();
    }

},     ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍