topic Re: Print field value in an alert box in ArcGIS JavaScript Maps SDK Questions

Print field value in an alert box

nabsabt — Tue, 04 May 2021 16:50:10 GMT

Hi! I'm kind of new to esri API, and I need to resolve a task. My job is to print out AGE_10_14 field values in an alert, where STATE_NAME = 'California'. I could not find any documentation, neither post, which could give me a guide. I accept any help gratefully! My code is:

require([

"esri/config",

"esri/Map",

"esri/views/MapView",

"esri/layers/FeatureLayer",

"esri/renderers/ClassBreaksRenderer",

"esri/symbols/SimpleFillSymbol",

"dojo/_base/Color",

"esri/Graphic"

], function(esriConfig,Map, MapView, FeatureLayer, Extent ) {

const map = new Map({

basemap: "arcgis-topographic"

});

const populationRenderer = {

type: "simple",

symbol: {

color: "#BA55D3",

type: "simple-fill",

style: "solid"

}

const view = new MapView({

container: "viewDiv",

map: map,

center: [-105.80543,38.02700],

zoom: 5

});

USACounties = new FeatureLayer({

url: "https://services.arcgis.com/P3ePLMYs2RVChkJx/ArcGIS/rest/services/USA_Counties_Generalized/FeatureServer/0",

definitionExpression: "STATE_NAME = 'California'",

renderer: populationRenderer

});

map.add(USACounties, 0);

});

Re: Print field value in an alert box

KenBuja — Tue, 04 May 2021 17:37:24 GMT

When do you want it to pop up the alert? When the user clicks on the map? When the map is ready to use?

Re: Print field value in an alert box

nabsabt — Tue, 04 May 2021 17:40:47 GMT

When the map (feature layer) is loaded, there's not any restriction to it.

Re: Print field value in an alert box

KenBuja — Tue, 04 May 2021 17:47:30 GMT

This is a good blog that talks about when items are ready: https://odoe.net/blog/when-are-layers-done

Re: Print field value in an alert box

nabsabt — Tue, 04 May 2021 18:10:06 GMT

Yes, but my issue is that I don't know, how to print field values to anywhere (alert, console, or just put them in an array, doesn't matter) =\ I could not find any simple solution for that, but probably there is.

Re: Print field value in an alert box

KenBuja — Tue, 04 May 2021 19:32:40 GMT

Here's an example of getting an alert when clicking on a feature

<!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <meta name="viewport" content="initial-scale=1, maximum-scale=1, user-scalable=no"> <title>Clicking on a layer with JS API 4</title> <link rel="stylesheet" href="https://js.arcgis.com/4.19/esri/themes/light/main.css" /> <style> html, body, #viewDiv { padding: 0; margin: 0; height: 100%; width: 100%; } </style> <script src="https://js.arcgis.com/4.19/"></script> <script> var map; require(["esri/Map", "esri/views/MapView", "esri/layers/FeatureLayer"], function (Map, MapView, FeatureLayer) { const map = new Map({ basemap: "arcgis-topographic" }); const populationRenderer = { type: "simple", symbol: { color: "#BA55D3", type: "simple-fill", style: "solid" } } const view = new MapView({ container: "viewDiv", map: map, center: [-105.80543, 38.02700], zoom: 5 }); USACounties = new FeatureLayer({ url: "https://services.arcgis.com/P3ePLMYs2RVChkJx/ArcGIS/rest/services/USA_Counties_Generalized/FeatureServer/0", definitionExpression: "STATE_NAME = 'California'", renderer: populationRenderer, outFields: ['*'] }); map.add(USACounties, 0); view.on('click', (event) => { view.hitTest(event) .then((response) => { console.log(response.results[0].graphic.attributes['AGE_10_14']); }); }); }); </script> </head> <body> <div id="viewDiv"></div> </body> </html>