This sample demonstrates how to create a PieChartRenderer. Pie chart visualizations are used for visualizing multiple attribute values of a feature in one glance in point and polygon layers.
This app uses pie charts to visualize the highest levels of education attained by the population in each county. The value and color of each pie slice is specified in the attributes property. The size of each pie is driven by a visual variable based on the number of people represented in each county.
Define the pie chart renderer with visual variables
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const layer = new FeatureLayer({
portalItem: {
id: "a7c5a8c8ea42416e8bd92df9872cc51b",
},
renderer: {
type: "pie-chart", // autocasts as new PieChartRenderer
size: 10,
attributes: [
{
color: "#ed5151",
label: "No high school diploma",
field: "SOMEHS_CY",
},
{
field: "HSGRAD_CY",
color: "#149ece",
label: "High school diploma",
},
{
field: "CollegeEducated",
color: "#a7c636",
label: "College educated",
},
],
// polygon fill behind pie chart
backgroundFillSymbol: {
type: "simple-fill", // autocasts as new SimpleFillSymbol
color: [127, 127, 127, 0.2],
outline: {
width: 1,
color: [255, 255, 255, 0.3],
},
},
outline: {
width: 1.5,
color: "grey",
},
visualVariables: [
{
type: "size", // size visual variable based on population represented in each pie
valueExpression: "$feature.SOMEHS_CY + $feature.HSGRAD_CY + $feature.CollegeEducated",
minDataValue: 20000,
maxDataValue: 500000,
minSize: 12,
maxSize: 48,
},
],
},
});