topic Re: Select points within polygon of separate layers in ArcGIS JavaScript Maps SDK Questions

Select points within polygon of separate layers

ClintonLunn — Sat, 11 Dec 2021 15:37:11 GMT

Hi all,

I am trying to achieve something similar to a Select by Location operation. I am using the Javascript API 4.6. I have 2 layers: 1 is a point layer, and the second is a polygon layer of city boundaries. Essentially, I would like to select a city and return all of the points within that city boundary.

What I have done:

I am using the search widget to enable me to text search the layer, where I have connected my layer of points. In this search widget, I can filter on a where statement, or geometry.

I have been able to successfully use the where statement when searching for objects within the same layer, but have not been able to get the filter by geometry to work. Here is a snippet of what I have come up with so far. In the console, it is showing that I am returning geometry objects, and it doesn't throw an error when I try to set the searchWidget geometry to the response geometry. However, it still returns points outside of my city boundary.

     //on change, get the value (name) of the city
    var city = document.getElementById("filterCityPanel");
    var cityStr = query("#filterCityPanel").on("change", function(e) {
            
      var task = new QueryTask({
        url: url,
      });
    
      var params = new Query();
      params.returnGeometry = true;
      params.where = "name = '" + e.target.value + "'";
      params.outFields = ["name"];

      task.execute(params)
      .then(function(response) {
      searchWidget.sources.items[0].filter.geometry = response.features[0].geometry;
      }) 
    });‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

Thank you!

Clinton Lunn

Re: Select points within polygon of separate layers

RobertScheitlin__GISP — Fri, 23 Feb 2018 19:22:15 GMT

Clinton,

Once you have applied the filter to the source you still need to execute a search for the filter to take affect.

Re: Select points within polygon of separate layers

ClintonLunn — Sat, 11 Dec 2021 15:37:14 GMT

Robert,

I am not sure if I understand what you mean. Do you mean once I filter to a city and then do a text search inside of my search widget?

I have been able to successfully get the where filter to execute. However, this was done on the same layer. See below for example:

// build select panel for quad (url, field name, dropdown label, dom ID)    
buildSelectPanel(URL, "quad", "Filter by Quad", "filterQuadPanel");

    var quad = document.getElementById("filterQuadPanel");
    var quadStr = query("#filterQuadPanel").on("change", function(e) {
      quadStr = e.target.value.toUpperCase();
      var searchQuery = "quad = '" + quadStr + "'";
      searchWidget.sources.items[0].filter.where = searchQuery;
    
    });‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

Thank you for the speedy response!

Clinton

Re: Select points within polygon of separate layers

RobertScheitlin__GISP — Fri, 23 Feb 2018 19:38:13 GMT

Do you mean once I filter to a city and then do a text search inside of my search widget? Yes

Re: Select points within polygon of separate layers

ClintonLunn — Fri, 23 Feb 2018 19:44:54 GMT

Robert,

If I am understanding you correctly, I have done that. Once I apply a filter from the first post, I then go to my search widget and enter an ID number of the field that I am searching for, and in the suggested results, it will still return from outside of my selection area.

Thank you,

Clinton

Re: Select points within polygon of separate layers

RobertScheitlin__GISP — Fri, 23 Feb 2018 19:48:35 GMT

Is the filter geometry the same spatial reference as the data being searched?

Re: Select points within polygon of separate layers

ClintonLunn — Fri, 23 Feb 2018 19:54:58 GMT

Robert,

Yes, they are both the same spatial reference.

Thank you,

Clinton

Re: Select points within polygon of separate layers

RobertScheitlin__GISP — Fri, 23 Feb 2018 19:58:32 GMT

Hmm... Sounds like there may be an issue with the search widget then.

I would get away from using the search widget and Just use a filtering select populated using the results of the first query.

Re: Select points within polygon of separate layers

mukulchavan — Wed, 23 Sep 2020 06:23:30 GMT

Hi Clinton,

I am looking for API which will return boundary coordinates of cities. You have mentioned in your question that you are drawing polygon for city boundaries, can you help me here? I need an api which provide those details of jurisdictional boundary of city.

Thanks & Regards

Mukul