Create a map view

This sample demonstrates how to load a webmap and create a map view.

How to use the sample

Clone the sample repo and copy this widget's folder (within widgets) to the client/your-extensions/widgets folder of your Experience Builder installation.

How it works

In React, sometimes you might need to interact directly with DOM nodes or React elements created in the render method. This is possible using React's React.createRef() method. Using the mapContainer property the React.createRef<HTMLDivElement>() method is assigned so it can be referenced throughout the widget/component. There is also some properties assigned to interfaces such as MapView, WebMap, and __esri.WatchHandle coming from the ArcGIS API for JavaScript. In addition, the MapViewManager class is used to get the instance of the app's mapview manager.

export default class Widget extends React.PureComponent<AllWidgetProps<{}> & ExtraProps, {}>{
  mapContainer = React.createRef<HTMLDivElement>();
  mapView: MapView;
  webMap: WebMap;
  extentWatch: __esri.WatchHandle;

  mvManager: MapViewManager = MapViewManager.getInstance();

The webmapDS.map, is the data source and this.mapContainer.current is a reference to the node created using React.createRef(). Basically, these are the properties that are passed into the constructor for the MapView using the interface for MapViewProperties.

const options: __esri.MapViewProperties = {
        map: webmapDs.map,
        container: this.mapContainer.current
      };

To create the MapView, the createJimuMapView() method is called with these properties: the widget that creates the object via mapWidgetId: this.props.id, the map view object view: new MapView(options), and the data source(webmap) datasourceId: webmapDs.id that creates the view.

this.mvManager.createJimuMapView({
        mapWidgetId: this.props.id,
        view: new MapView(options),
        datasourceId: webmapDs.id,
        isActive: true
      })