The sublayers property of a MapImageLayer allows you to dynamically set renderers on the fly for layers in a map service. To do so, you must reference the layer ID of the service layer and assign a renderer to the renderer property of the sublayer.
const layer = new MapImageLayer({
url: "https://sampleserver6.arcgisonline.com/arcgis/rest/services/USA/MapServer",
sublayers: [
{
id: 2,
renderer: {
type: "simple", // autocasts as new SimpleRenderer()
symbol: {
type: "simple-marker", // autocasts as new SimpleMarkerSymbol()
size: 3,
color: "white"
}
}
}
]
});To see the default renderers for layers in the map service, either remove the references to the renderers defined in this sample or view the MapImageLayer - Toggle sublayer visibility sample.