Note: Support for 3D on mobile devices may vary, view the system requirements for more information.

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.

var 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 renferences to the renderers defined in this sample or view the MapImageLayer - Toggle sublayer visibility sample.