Graduated circles showing population for US counties.
<!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>Graduated Symbols with Polygon Layer - Scale Dependent</title>
<link rel="stylesheet" href="https://js.arcgis.com/3.46/esri/css/esri.css">
<style>
html, body, #map {
height: 100%;
margin: 0;
}
#infopane {
position: absolute;
width: 300px;
top: 0;
right: 0;
background-color: rgba(150,150,150,0.75);
padding: 10px;
border-radius: 0 0 0 10px;
font-family: Segoe UI;
}
.esriLegendServiceLabel, #info-title {
font-weight: 600;
}
.hidden {
display: none;
}
#toggle-button {
cursor: pointer;
}
</style>
<script src="https://js.arcgis.com/3.46/"></script>
<script>
require([
"esri/map", "esri/layers/FeatureLayer", "esri/dijit/Legend", "esri/symbols/SimpleMarkerSymbol", "esri/symbols/SimpleLineSymbol", "esri/symbols/SimpleFillSymbol",
"esri/Color", "esri/renderers/ClassBreaksRenderer", "esri/renderers/ScaleDependentRenderer", "esri/InfoTemplate", "dojo/_base/array", "dojo/dom", "dojo/query", "dojo/domReady!"
], function(Map, FeatureLayer, Legend, SimpleMarkerSymbol, SimpleLineSymbol, SimpleFillSymbol, Color, ClassBreaksRenderer, ScaleDependentRenderer, InfoTemplate, array, dom, query) {
var map = new Map("map", {
basemap: "gray-vector",
center: [-98.5795,39.828175],
zoom: 4
});
var layer = new FeatureLayer("https://services.arcgis.com/V6ZHFr6zdgNZuVG0/arcgis/rest/services/USA_Counties/FeatureServer/0", {
outFields: ["*"],
infoTemplate: new InfoTemplate("${NAME}, ${STATE_NAME}", "Population in 1999: ${POP1999}")
});
var createRenderer = function(enlarge){
var renderer = new ClassBreaksRenderer(null, "POP1999");
var outline = new SimpleLineSymbol().setWidth(0.5).setColor(new Color([43, 101, 236, 1]));
var color = new Color([43, 101, 236, 0.75]);
var classBreaks = [{minValue: 0, maxValue: 20000, size: 2}, {minValue: 20000, maxValue: 50000, size: 4}, {minValue: 50000, maxValue: 100000, size: 6}, {minValue: 100000, maxValue: 1000000, size: 9}, {minValue: 1000000, maxValue: 10000000, size: 10}];
array.forEach(classBreaks, function(classBreak){
renderer.addBreak(classBreak.minValue, classBreak.maxValue, new SimpleMarkerSymbol(SimpleMarkerSymbol.STYLE_CIRCLE, (classBreak.size * enlarge), outline, color));
});
return renderer;
};
var rendererInfos = [];
for (var i = 4; i < 9; i++) {
rendererInfos.push({
renderer: createRenderer(Math.pow(2, i - 4)),
minZoom: i,
maxZoom: i
});
}
var scaleRenderer = new ScaleDependentRenderer({
rendererInfos: rendererInfos
});
scaleRenderer.backgroundFillSymbol = new SimpleFillSymbol().setColor(new Color([0, 0, 0, 0])).setOutline(new SimpleLineSymbol().setWidth(0));
layer.setRenderer(scaleRenderer);
map.addLayers([ layer ]);
var legend = new Legend({
map: map,
layerInfos: [{
layer: layer,
title: "Legend"
}]
}, "legend");
map.on("layers-add-result", function(layer){
legend.startup();
});
dom.byId("toggle-button").onclick = function(){
query(".toggle-pane").toggleClass("hidden");
};
});
</script>
</head>
<body>
<div id="map"></div>
<div id="infopane">
<div id="toggle-button">[Toggle/expand information pane]</div>
<div class="toggle-pane">
<h1 id="info-title">Big Counties vs. Small Counties</h1>
<p>Graduated symbols provide an alternate way to symbolize a polygon layer. This is a suitable approach to visualize population-based data as it is not affected by the area of polygons.</p>
<p>The symbols on this map are scale-dependent. As you zoom in, the sizes of symbols are sized accordingly.</p>
<p>Population of county is displayed on map with the size of circle. This map shows the distribution of the "big counties" and "small counties" in the US.</p>
<div id="legend"></div>
</div>
</div>
</body>
</html>