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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<meta
name="viewport"
content="initial-scale=1,maximum-scale=1,user-scalable=no"
/>
<title>Point clustering - query clusters | Sample | ArcGIS API for JavaScript 4.20</title>
<link rel="stylesheet" href="https://js.arcgis.com/4.20/esri/themes/light/main.css" />
<script src="https://js.arcgis.com/4.20/"></script>
<style>
html,
body,
#viewDiv {
height: 100%;
width: 100%;
margin: 0;
padding: 0;
background-color: white;
}
#infoDiv {
background: white;
padding: 10px;
}
table td {
padding: 3px;
}
table.popup td.num {
text-align: right;
}
table.popup tr.head {
text-align: center;
font-weight: bold;
background-color:rgba(50, 50, 50,0.08);
}
.table-container {
width:100%;
height:100%;
text-align: center;
}
table {
margin: 0 auto;
}
</style>
<script>
require([
"esri/WebMap",
"esri/Graphic",
"esri/views/MapView",
"esri/layers/FeatureLayer",
"esri/widgets/Legend",
"esri/widgets/Expand",
"esri/smartMapping/labels/clusters",
"esri/smartMapping/popup/clusters",
"esri/core/watchUtils",
"esri/symbols/support/symbolUtils",
"esri/geometry/geometryEngine",
], (
WebMap,
Graphic,
MapView,
FeatureLayer,
Legend,
Expand,
clusterLabelCreator,
clusterPopupCreator,
watchUtils,
symbolUtils,
geometryEngine
) => {
let layerView;
const layer = new FeatureLayer({
portalItem: {
id: "eb54b44c65b846cca12914b87b315169"
},
outFields: [ "capacity_mw" ]
});
const map = new WebMap({
basemap: {
portalItem: {
id: "75a08e8cd8b64dcfa6945bb7f624ccc5"
}
},
layers: [ layer ]
});
const view = new MapView({
container: "viewDiv",
map,
extent: {
spatialReference: {
latestWkid: 3857,
wkid: 102100
},
xmin: -15327459,
ymin: 2740044,
xmax: -6076744,
ymax: 6878650
},
popup: {
dockEnabled: true,
dockOptions: {
breakpoint: false,
position: "top-right"
}
}
});
view.ui.add( new Expand({
content: new Legend({ view }),
view
}), "top-left");
layer
.when()
.then(generateClusterConfig)
.then( async (featureReduction) => {
// sets generated cluster configuration on the layer
layer.featureReduction = featureReduction;
// the layer view is needed for querying clusters
layerView = await view.whenLayerView(layer);
// Disable clustering when user zooms beyond a 1:50,000 scale level
// Re-enable clustering when the user zooms out to a scale smaller than 1:50,000
view.watch("scale", (scale) => {
layer.featureReduction = view.scale > 50000 ? featureReduction : null;
});
})
.catch((error) => {
console.error(error);
});
async function generateClusterConfig(layer) {
// generates default popupTemplate
const popupTemplate =
await clusterPopupCreator
.getTemplates({
layer
})
.then((popupTemplateResponse) => popupTemplateResponse.primaryTemplate.value);
// Add actions for exploring the features of each cluster
popupTemplate.actions = [
{
title: "Statistics",
id: "statistics",
className: "esri-icon-line-chart"
},
{
title: "Convex hull",
id: "convex-hull",
className: "esri-icon-polygon"
},
{
title: "Show features",
id: "show-features",
className: "esri-icon-maps"
}
];
// generates default labelingInfo
const { labelingInfo, clusterMinSize } =
await clusterLabelCreator
.getLabelSchemes({
layer, view
})
.then((labelSchemes) => labelSchemes.primaryScheme);
return {
type: "cluster",
popupTemplate,
labelingInfo,
clusterMinSize
};
}
view.popup.on("trigger-action", (event) => {
clearViewGraphics();
const popup = view.popup;
const selectedFeature = popup.selectedFeature && popup.selectedFeature.isAggregate
const id = event.action.id;
if(id === "convex-hull"){
displayConvexHull(view.popup.selectedFeature);
}
if(id === "show-features"){
displayFeatures(view.popup.selectedFeature);
}
if(id === "statistics"){
calculateStatistics(view.popup.selectedFeature);
}
});
watchUtils.watch(view, ["scale", "popup.selectedFeature", "popup.visible"], clearViewGraphics);
let convexHullGraphic = null;
let clusterChildGraphics = [];
function clearViewGraphics(){
view.graphics.remove(convexHullGraphic);
view.graphics.removeMany(clusterChildGraphics);
}
// displays all features from a given cluster in the view
async function displayFeatures(graphic){
processParams(graphic, layerView);
const query = layerView.createQuery();
query.aggregateIds = [graphic.getObjectId()];
const { features } = await layerView.queryFeatures(query);
features.forEach( async (feature) => {
const symbol = await symbolUtils.getDisplayedSymbol(feature)
feature.symbol = symbol;
view.graphics.add(feature);
});
clusterChildGraphics = features;
}
async function displayConvexHull(graphic){
processParams(graphic, layerView);
const query = layerView.createQuery();
query.aggregateIds = [graphic.getObjectId()];
const { features } = await layerView.queryFeatures(query);
const geometries = features.map( feature => feature.geometry );
const [ convexHull ] = geometryEngine.convexHull(geometries, true);
convexHullGraphic = new Graphic({
geometry: convexHull,
symbol: {
type: "simple-fill",
outline: {
width: 1.5,
color: [ 75, 75, 75, 1 ]
},
style: "none",
color: [ 0, 0, 0, 0.1 ]
}
});
view.graphics.add(convexHullGraphic);
}
// calculates set statistics for features in a cluster
// and displays them in the cluster popup
async function calculateStatistics(graphic){
processParams(graphic, layerView);
const query = layerView.createQuery();
query.aggregateIds = [graphic.getObjectId()];
query.groupByFieldsForStatistics = [ "fuel1" ];
query.outFields = [ "capacity_mw", "fuel1" ];
query.orderByFields = [ "num_features desc" ];
query.outStatistics = [
{
onStatisticField: "capacity_mw",
outStatisticFieldName: "capacity_total",
statisticType: "sum"
},
{
onStatisticField: "1",
outStatisticFieldName: "num_features",
statisticType: "count"
},
{
onStatisticField: "capacity_mw",
outStatisticFieldName: "capacity_max",
statisticType: "max"
}
];
const { features } = await layerView.queryFeatures(query);
const stats = features.map( feature => feature.attributes);
let table = `
<div class="table-container">
<span style="font-size: 14pt"><strong>Summary by fuel type</strong></span>
<br/>
<br/>
<table class="esri-widget popup">
<tr class="head"><td>Fuel</td><td>Count</td><td>Capacity (mW)</td><td>Largest plant (mW)</td></tr>
`;
let totalCapacity = 0;
let totalCount = 0;
stats.forEach( stat => {
const fuel = stat.fuel1;
const total = stat.capacity_total;
const max = stat.capacity_max;
const count = stat.num_features;
totalCapacity += total;
totalCount += count;
table += `
<tr><td><span style:'font-weight:bolder'>${fuel}</span></td><td class="num">${count}</td><td class="num">${roundDecimals(total, 2).toLocaleString()}</td><td class="num">${roundDecimals(max, 2).toLocaleString()}</td></tr>
`;
});
table += `
</table>
</div>`;
view.popup.content = `
<div style="font-size: 12pt">
Number of features: <strong>${totalCount.toLocaleString()}</strong><br>
Total capacity (mW): <strong>${roundDecimals(totalCapacity, 2).toLocaleString()}</strong><br>
</div><br>
` + table;
}
function processParams(graphic, layerView){
if (!graphic || !layerView) {
throw new Error("Graphic or layerView not provided.");
}
if (!graphic.isAggregate) {
throw new Error("Graphic must represent a cluster.");
}
}
function roundDecimals(num, places){
return Math.round(num * Math.pow(10, places)) / Math.pow(10, places);
}
});
</script>
</head>
<body>
<div id="viewDiv"></div>
</body>
</html>
