Creating a Collection of FeatureLayerViews

MichaelNesius1 — Tue, 26 Apr 2022 17:24:26 GMT

Hi Esri Community,

I'm trying to build a Collection of FeatureLayerViews but I am getting a "W is not a function" when I execute try to .add(layerView)

Any suggestion would be greatly appreciated.

Codepen reproducing my error (code shown below)

require(["esri/Map", "esri/views/MapView", "esri/layers/FeatureLayer", "esri/views/layers/FeatureLayerView","esri/core/Collection"], function(Map, MapView, FeatureLayer, FeatureLayerView, Collection) { const map = new Map({ basemap: "dark-gray-vector" }); const view = new MapView({ container: "sceneDiv", map: map, center: [-73.95, 40.702], zoom: 12, padding: { right: 300 } }); /******************** * Add feature layers ********************/ // Create the FeatureLayers const FLUrls =[ {url:"https://sampleserver6.arcgisonline.com/arcgis/rest/services/EmergencyFacilities/FeatureServer/0", title: "Facilities", id: "Facilities"}, {url:"https://sampleserver6.arcgisonline.com/arcgis/rest/services/LocalGovernment/WaterValveInspections/FeatureServer/0", title: "Water", id: "Water"}, {url:"https://sampleserver6.arcgisonline.com/arcgis/rest/services/LocalGovernment/SewerManholeInspections/FeatureServer/0", title: "Sewer", id: "Sewer"} ] const FLs = FLUrls.map( (x) => ( new FeatureLayer({ url: x.url, title: x.title, id: x.id, visible: false } ) )); const show = (...a) => console.log(...a); const layerTitles = a => show(a.title); const layerIDs = a => show(a.id); const layerViews = a => { console.log("feature layer view a: " + a.title) view.whenLayerView(a) .then( layerView => { console.log("when layer view: " + layerView.layer.title) try{ featureLayersViews.add(layerView); // Not sure why add() is throwing "W is not a function" } catch(e) { console.error("\t" + e.message) } }) .catch(err => { console.log("error with feature layer view: " )//+ layerView.layer.title) console.error(err) }) }; const addLayerResults = results => { // Add the FeatureLayers to the map map.addMany(results) //console log the titles of the layers results.map(layerTitles) // pass the layers to a whenLayerView function that adds them to the view Collection results.map(layerViews) } //collection of FeatureLayers let FeatureLayerCollection = Collection.ofType(FeatureLayer); const featureLayers = new FeatureLayerCollection(); //collection of FeatureLayersViews let FeatureLayerViewCollection = Collection.ofType(FeatureLayerView); const featureLayersViews = new FeatureLayerViewCollection(); featureLayersViews.on("after-add", event => { console.log(`${event.item.title} was added to featureLayersViews collection`); }) featureLayers.on("after-add", event => { console.log(`${event.item.title} was added to featureLayers collection`); }) featureLayers.addMany(FLs); view.when( function () { console.log("View loaded "); Promise.all(featureLayers.map(a => a.load()).toArray()) .then(addLayerResults) .catch(show) } ) })

Re: Creating a Collection of FeatureLayerViews

ReneRubalcava — Tue, 26 Apr 2022 17:48:52 GMT

You don't need a typed Collection

Collection.ofType(FeatureLayerView)

When you do this, the Collection will try to initialize the added object as a new FeatureLayerView() and that doesn't work because it's already a class.

If this is for TypeScript, you can do this.

const featureLayersViews = new Collection<FeatureLayerView>();

topic Re: Creating a Collection of FeatureLayerViews in ArcGIS JavaScript Maps SDK Questions

Creating a Collection of FeatureLayerViews

Re: Creating a Collection of FeatureLayerViews