Tutorial: Change language labels | CesiumJS

Learn how to change language labels for styled basemap tiles.

Change language labels using API key authentication

The ArcGIS Static Basemap Tiles service provides access to raster basemap tiles for the world. The service supports a number of ArcGIS styles such as navigation, streets, outdoor, and light-gray. The tiles are returned as PNG files.

In this tutorial, you use the dropdown menu to toggle between different languages for the static basemap tiles.

Prerequisites

You need an ArcGIS Location Platform account.

ArcGIS Online and ArcGIS Enterprise accounts are not supported.

Steps

Get the starter app

Select a type of authentication and follow the steps to create a new app.

Choose API key authentication if you:

Want the easiest way to get started.
Want to build public applications that access ArcGIS Location Services and secure items.
Have an ArcGIS Location Platform or ArcGIS Online account.

Choose user authentication if you:

Want to build private applications.
Require application users to sign in with their own ArcGIS account and access resources their behalf.
Have an ArcGIS Online account.

To learn more about both types of authentication, go to Authentication.

You can choose one of the following to create a new CodePen:

Option 1: Complete the Display a scene tutorial; or,
Option 2: Start from the Display a scene tutorial .

Set up authentication

Create a new API key credential with the correct privileges to get an access token.

Go to the Create an API key tutorial and create an API key with the following privilege(s):
- Privileges
  - Location services > Basemaps > Static basemap tiles

Set developer credentials

Use the access token created in the previous step in your application.

Add a <script> element in the HTML <body> and create an accessToken variable to store your access token. Set YOUR_ACCESS_TOKEN with the access token you previously copied from your API key credentials.

Expand
Use dark colors for code blocks
    <script>

    /* Use for API key authentication */
    const accessToken = "YOUR_ACCESS_TOKEN";

    </script>
Expand

Use the OAuth credentials created in the previous step in your application.

In both the index.html and callback.html files, set the properties of clientId and redirectUri with the client ID and redirect URL of your OAuth credentials.

index.html
Use dark colors for code blocks
    /* Use for user authentication */
    const clientId = "YOUR_CLIENT_ID"; // Your client ID from OAuth credentials
    const redirectUri = ""YOUR_REDIRECT_URI""; // The redirect URL registered in your OAuth credentials
    const session = await arcgisRest.ArcGISIdentityManager.beginOAuth2({
      clientId,
      redirectUri,
      portal: "https://www.arcgis.com/sharing/rest" // Your portal URL
    });

    const accessToken = session.token;

callback.html
Use dark colors for code blocks
    arcgisRest.ArcGISIdentityManager.completeOAuth2({
      clientId: "YOUR_CLIENT_ID", // Your client ID from OAuth credentials
      redirectUri: "YOUR_REDIRECT_URI", // The redirect URL registered in your OAuth credentials
      portal: "https://www.arcgis.com/sharing/rest" // Your portal URL
    });

Run the app and ensure you can sign in successfully.

If you are unable to sign in, make sure you have the correct redirect URL and port. This URL varies based on your application and typically takes the format of https://<server>[:port]/callback.html or http://my-arcgis-app:/auth. For example, if you are running an application on http://127.0.0.1:5500/, set http://127.0.0.1:5500/callback.html as your redirect URL in the index.html and callback.html file and your developer credential. They all have to match!

Set the defaultAccessToken included with Cesium to authenticate requests to the ArcGIS services used in this tutorial.

index.html
Use dark colors for code blocks
    Cesium.ArcGisMapService.defaultAccessToken = accessToken;

Get a Cesium ion access token

All Cesium applications must use an access token provided through Cesium ion. This token allows you to access assets such as Cesium World Terrain in your application.

Go to your Cesium ion dashboard to generate an access token. Copy the key to your clipboard.

Create a cesiumAccessToken variable and replace YOUR_CESIUM_ACCESS_TOKEN with the access token you copied from the Cesium ion dashboard.

Use dark colors for code blocks
    <script>

    /* Use for API key authentication */
    const accessToken = "YOUR_ACCESS_TOKEN";

    // or

    /* Use for user authentication */
    // const session = await arcgisRest.ArcGISIdentityManager.beginOAuth2({
    //   clientId: "YOUR_CLIENT_ID", // Your client ID from OAuth credentials
    //   redirectUri: "YOUR_REDIRECT_URI", // The redirect URL registered in your OAuth credentials
    //   portal: "YOUR_PORTAL_URL" // Your portal URL
    // })

    // const accessToken = session.token;

    Cesium.ArcGisMapService.defaultAccessToken = accessToken;

    const cesiumAccessToken = "YOUR_CESIUM_ACCESS_TOKEN";

    </script>

Configure Cesium.Ion.defaultAccessToken with the Cesium access token to validate the application.

Use dark colors for code blocks
    <script>

    /* Use for API key authentication */
    const accessToken = "YOUR_ACCESS_TOKEN";

    // or

    /* Use for user authentication */
    // const session = await arcgisRest.ArcGISIdentityManager.beginOAuth2({
    //   clientId: "YOUR_CLIENT_ID", // Your client ID from OAuth credentials
    //   redirectUri: "YOUR_REDIRECT_URI", // The redirect URL registered in your OAuth credentials
    //   portal: "YOUR_PORTAL_URL" // Your portal URL
    // })

    // const accessToken = session.token;

    Cesium.ArcGisMapService.defaultAccessToken = accessToken;

    const cesiumAccessToken = "YOUR_CESIUM_ACCESS_TOKEN";

    Cesium.Ion.defaultAccessToken = cesiumAccessToken;

    </script>

Add a language selector

Add a menu that allows users to change the display language of your map. CesiumJS does not have a built-in selector widget, so you will create an HTML <select> element.

In the <body> element, add a select element, which you will populate in a later step.

Use dark colors for code blocks

  <body>
    <div id="cesiumContainer"></div>

    <div id="language-wrapper">
      <select id="language"></select>
    </div>

  </body>

In the <head> tag, add CSS that will position the <select> menu element and its wrapper in the upper right corner and provide styling.

Use dark colors for code blocks
    <style>
    html,
    body,
    #cesiumContainer {
      margin: 0;
      padding: 0;
      width: 100%;
      height: 100%;
    }


    #language-wrapper {
      position: absolute;
      top: 20px;
      left: 20px;
      background: rgba(255, 255, 255, 0);
    }

    #language {
      font-size: 16px;
      padding: 4px 8px;
    }


    </style>

Update the camera's viewpoint

Change the camera's destination to 8.20, 46.90, 300000. This will focus the camera on Switzerland.

Use dark colors for code blocks
    viewer.camera.setView({

      destination: Cesium.Cartesian3.fromDegrees(8.20, 46.90, 250000)

    });

Set the basemap language

When the scene loads, initialize the app to display the basemap in English.

Create a function called url that takes a language as a parameter. This will create the URL of the static basemap tiles for that specified language.

Expand
Use dark colors for code blocks
    const basemapEnum = "arcgis/navigation";
    const baseUrl = "https://static-map-tiles-api.arcgis.com/arcgis/rest/services/static-basemap-tiles-service/v1";

    const url = (language) => `${baseUrl}/${basemapEnum}/static/tile/{z}/{y}/{x}?token=${accessToken}&language=${language}`;

Expand

Create a defaultLanguage variable for the basemap, which is en for English.

Expand
Use dark colors for code blocks
    const basemapEnum = "arcgis/navigation";
    const baseUrl = "https://static-map-tiles-api.arcgis.com/arcgis/rest/services/static-basemap-tiles-service/v1";

    const url = (language) => `${baseUrl}/${basemapEnum}/static/tile/{z}/{y}/{x}?token=${accessToken}&language=${language}`;

    const defaultLanguage = "en";
Expand

Import arcgisRest.request() to make a request to the Static Basemap Tiles service. This dynamically fetches the available basemap languages and populates the select element.

Use dark colors for code blocks
    <!-- ArcGIS REST JS -->
    <script src="https://unpkg.com/@esri/arcgis-rest-request@4/dist/bundled/request.umd.js"></script>

Expand
Use dark colors for code blocks
    const selector = document.querySelector("#language");

    arcgisRest.request(`${baseUrl}/self`, {
      httpMethod: "GET",
      authentication: arcgisRest.ApiKeyManager.fromKey(accessToken)
    }).then((response) => {
      response.languages.forEach((language) => {
        const option = document.createElement("option");
        option.value = language.code;
        option.textContent = language.name;
        selector.appendChild(option);
      });
    });
Expand

Fetch the service URL to retrieve the basemap JSON. Then, create an UrlTemplateImageryProvider object from the JSON.

Expand
Use dark colors for code blocks
    arcgisRest.request(`${baseUrl}/${basemapEnum}/static`, {
      httpMethod: "GET",
      authentication: arcgisRest.ApiKeyManager.fromKey(accessToken)
    }).then((data) => {

      const imageryProvider = new Cesium.UrlTemplateImageryProvider({
        url: url(defaultLanguage),
        tileHeight: 512,

      });

    });
Expand

Remove the basemap attribution code because you will add it dynamically instead in the next step.

Use dark colors for code blocks
      fetch(`${baseUrl}?token=${accessToken}`)
        .then((response) => response.json())
        .then((data) => {
          const basemapAttribution = new Cesium.Credit(data.copyrightText, false);
          viewer.creditDisplay.addStaticCredit(basemapAttribution);
        });

Create a basemapCredit and instantiate a Credit object from the copyrightText string of the JSON. CesiumJS does not provide attribution automatically for Static Basemap Tiles service. Therefore, you are required to add this attribution manually.

Expand
Use dark colors for code blocks
    let basemapCredit;

    const selector = document.querySelector("#language");

    arcgisRest.request(`${baseUrl}/self`, {
      httpMethod: "GET",
      authentication: arcgisRest.ApiKeyManager.fromKey(accessToken)
    }).then((response) => {
      response.languages.forEach((language) => {
        const option = document.createElement("option");
        option.value = language.code;
        option.textContent = language.name;
        selector.appendChild(option);
      });
    });

    arcgisRest.request(`${baseUrl}/${basemapEnum}/static`, {
      httpMethod: "GET",
      authentication: arcgisRest.ApiKeyManager.fromKey(accessToken)
    }).then((data) => {

      basemapCredit = data.copyrightText;

      const imageryProvider = new Cesium.UrlTemplateImageryProvider({
        url: url(defaultLanguage),
        tileHeight: 512,

        credit: basemapCredit

      });

    });
Expand

Add the imageryProvider to the viewer.

Expand
Use dark colors for code blocks
    arcgisRest.request(`${baseUrl}/${basemapEnum}/static`, {
      httpMethod: "GET",
      authentication: arcgisRest.ApiKeyManager.fromKey(accessToken)
    }).then((data) => {

      basemapCredit = data.copyrightText;

      const imageryProvider = new Cesium.UrlTemplateImageryProvider({
        url: url(defaultLanguage),
        tileHeight: 512,

        credit: basemapCredit

      });

      viewer.imageryLayers.addImageryProvider(imageryProvider);

    });
Expand

Run the code to ensure that the <select> element contains different language enumerations.

Add an event listener

Add an event listener for the selector.

Expand
Use dark colors for code blocks
    selector.addEventListener("change", (e) => {

    });
Expand

Create a new UrlTemplateImageryProvider using the selected language.

Expand
Use dark colors for code blocks
    selector.addEventListener("change", (e) => {

      const newImageryProvider = new Cesium.UrlTemplateImageryProvider({
        url: url(e.target.value),
        tileWidth: 512,
        tileHeight: 512,
        credit: basemapCredit
      });

    });
Expand

Update the viewer with the new language.

Expand
Use dark colors for code blocks
    selector.addEventListener("change", (e) => {

      const newImageryProvider = new Cesium.UrlTemplateImageryProvider({
        url: url(e.target.value),
        tileWidth: 512,
        tileHeight: 512,
        credit: basemapCredit
      });

      viewer.imageryLayers.removeAll();
      viewer.imageryLayers.addImageryProvider(newImageryProvider);

    });
Expand

Run the app

Run the app.

The map should be displayed in English and you should be able to use the controls to switch between language labels.

What's next?

Learn how to use additional location services in these tutorials:

Change the base layer

Change the styled basemap tile in a scene.

Display multiple basemap layers

Add multiple basemap layers from different services to your scene.