Display a web map

Learn how to display a map from a web map stored in ArcGIS.

A web map is a map stored as an item in ArcGIS Online. A web map item contains all of the configuration settings for the map (in JSON format) such as the basemap layer, data layers, layer styles, and pop-up settings. Applications can access and display a web map using its item ID.

In this tutorial, you will load and display a pre-configured web map stored in ArcGIS Online.

Prerequisites

You need an ArcGIS Developer or ArcGIS Online account to access the dashboard and create an API key.

Steps

Create a new pen

To get started, either complete the Display a map tutorial or .

Set the API key

To access ArcGIS services, you need an API key.

Go to your dashboard to get an API key.
In CodePen, set the apiKey to your key, so it can be used to access basemap layer and location services.

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esriConfig.apiKey = "YOUR_API_KEY";
const map = new Map({
  basemap: "arcgis/topographic" // basemap styles service
});

Add modules

In the require statement, delete the Map module. Add the WebMap, ScaleBar, and Legend modules.

The ArcGIS Maps SDK for JavaScript is available as AMD modules and ES modules, but this tutorial is based on AMD. The AMD require function uses references to determine which modules will be loaded – for example, you can specify "esri/Map" for loading the Map module. After the modules are loaded, they are passed as parameters (e.g. Map) to the callback function where they can be used in your application. It is important to keep the module references and callback parameters in the same order. For more information on the different types of modules, visit the Introduction to Tooling guide topic.

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  <script>
    require([
      "esri/config",
      "esri/Map",
      "esri/WebMap",
      "esri/views/MapView",
      "esri/widgets/ScaleBar",
      "esri/widgets/Legend"
    ], function(esriConfig, WebMap, MapView, ScaleBar, Legend) {
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Load the web map

You can use the portal item ID to create a WebMap. The web map will be passed to the view.

Delete the code that creates the Map.

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    esriConfig.apiKey = "YOUR_API_KEY";

     const map = new Map ({
       basemap: "arcgis/topographic" // basemap styles service
     });

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Create a WebMap. Set the portalItem ID to 41281c51f9de45edaf1c8ed44bb10e30.

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    esriConfig.apiKey = "YOUR_API_KEY";

      const webmap = new WebMap({
        portalItem: {
          id: "41281c51f9de45edaf1c8ed44bb10e30"
        }
      });

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Update the map property in the MapView with the webmap element. Remove the center and zoom properties, since the web map provides positioning information.

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      const webmap = new WebMap({
        portalItem: {
          id: "41281c51f9de45edaf1c8ed44bb10e30"
        }
      });

      const view = new MapView({
        container: "viewDiv",

        map: map,
        center: [-118.80500,34.02700],
        zoom: 13,

        map: webmap

      });
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At the top-right, click Run to verify that the web map has been successfully loaded and displays.

Add widgets

Use the Legend and ScaleBar widgets to add more context to the application. The Legend widget displays labels and symbols for layers visible in the view. The ScaleBar can display units in either metric or non-metric values.

Create a ScaleBar. Add the scalebar to the bottom-left of the view.

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      const view = new MapView({
        container: "viewDiv",

        map: webmap

      });

      const scalebar = new ScaleBar({
        view: view
      });

      view.ui.add(scalebar, "bottom-left");

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Create a Legend to display feature information. Add the legend to the top-right of the view.

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      const scalebar = new ScaleBar({
        view: view
      });

      view.ui.add(scalebar, "bottom-left");

    const legend = new Legend ({
        view: view
      });
      view.ui.add(legend, "top-right");
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Run the App

In CodePen, run your code to display the map.

You should now see a scale bar displaying scale (in miles), along with a legend that displays layer information contained in the web map.

What's next?

Learn how to use additional API features and ArcGIS services in these tutorials: