Change language labels for basemap styles

Learn how to localize place labels in a basemap.

Change language labels for basemap styles using API key authentication

The basemap styles service provides a number of different styles that you can use in your MapLibre GL JS applications. Each style accepts a language parameter, which allows you to localize place labels. There are currently over 30 different languages available.

In this tutorial, you use a <select> dropdown menu to toggle between a number of different place label languages.

Prerequisites

An ArcGIS Location Platform or ArcGIS Online account.

Steps

Get the starter app

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

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

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

Set up authentication

Create developer credentials in your portal for the type of authentication you selected.

Create a new API key credential with the correct privileges to access the resources used in this tutorial.

Go to the Create an API key tutorial and create an API key with the following privilege(s):
- Privileges
  - Location services > Basemaps
Copy the API key access token to your clipboard when prompted.

Set developer credentials

Use the API key or OAuth developer credentials so your application can access location services.

Update the accessToken variable to use your API key.

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    /* Use for API key authentication */
    const accessToken = "YOUR_ACCESS_TOKEN"
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In both the index.html and callback.html files, replace YOUR_CLIENT_ID and YOUR_REDIRECT_URL with the client ID and redirect URL of your OAuth credentials.

index.html
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    /* 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
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    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!

Add a language selector

Add a menu that allows users to change display language of your map. To accomplish this, use a standard html <select> element.

Create a <div> tag to contain the <select> dropdown menu, which you will populate in a later step.

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  </style>
  <script src=https://unpkg.com/maplibre-gl@5.1.0/dist/maplibre-gl.js></script>
  <link href=https://unpkg.com/maplibre-gl@5.1.0/dist/maplibre-gl.css rel="stylesheet" />

  <!-- REST JS -->
  <script src="https://unpkg.com/@esri/arcgis-rest-request@4/dist/bundled/request.umd.js"></script>

</head>


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

  <div id="languages-wrapper">

    <select id="languages"></select>

  </div>
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In the <style> element, add CSS styling to the languages-wrapper and languages.

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  <style>
    html,
    body,
    #map {
      padding: 0;
      margin: 0;
      height: 100%;
      width: 100%;
      font-family: Arial, Helvetica, sans-serif;
      font-size: 14px;
      color: #323232;
    }


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

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


  </style>
  <script src=https://unpkg.com/maplibre-gl@5.1.0/dist/maplibre-gl.js></script>
  <link href=https://unpkg.com/maplibre-gl@5.1.0/dist/maplibre-gl.css rel="stylesheet" />
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Set the basemap

Use a function to reference the basemap styles service and a language enumeration to update the map. This will be used when a selection is made.

Create a baseUrl and a url element. The url function will use the baseUrl to create a reference to a basemap style in a specified language.

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  <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;

    const basemapEnum = "arcgis/outdoor";
    const map = new maplibregl.Map({
      container: "map", // the id of the div element
      style: `https://basemapstyles-api.arcgis.com/arcgis/rest/services/styles/v2/styles/${basemapEnum}?token=${accessToken}`,
      zoom: 2, // starting zoom
      center: [48.8790, 35.7088] // starting location [longitude, latitude]
    });

    const baseUrl = "https://basemapstyles-api.arcgis.com/arcgis/rest/services/styles/v2/styles";
    const url = (language) => `${baseUrl}/arcgis/outdoor?token=${accessToken}&language=${language}`;
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Set the style of the map using the url function and a language code.

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    const baseUrl = "https://basemapstyles-api.arcgis.com/arcgis/rest/services/styles/v2/styles";
    const url = (language) => `${baseUrl}/arcgis/outdoor?token=${accessToken}&language=${language}`;

    const setLanguage = (language) => {
      // Instantiate the given basemap layer.
      map.setStyle(url(language));
    };
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Access the language selector using its id.

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    const languageSelectElement = document.querySelector("#languages");

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

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  <!-- REST JS -->
  <script src="https://unpkg.com/@esri/arcgis-rest-request@4/dist/bundled/request.umd.js"></script>

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    const languageSelectElement = document.querySelector("#languages");

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

    })
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Call setBasemap to initialize the basemap layer to the first basemap in the select element.

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    arcgisRest.request(`${baseUrl}/self`, {
      httpMethod: "GET"
    }).then(response => {
      response.styles.forEach(style => {
        const option = document.createElement("option");
        option.value = style.path
        option.textContent = style.name
        basemapsSelectElement.appendChild(option)
      })

      setBasemap(response.styles[0].path)

    })
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Add an event listener

Use an event listener to register a basemap change in the <select> element and to update the map.

Add an event listener to update the map when a new language is selected.

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    const languageSelectElement = document.querySelector("#languages");

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

      setBasemap(response.languages[0].code)

    })

    languageSelectElement.addEventListener("change", (e) => {
      setLanguage(e.target.value);
      console.log(e.target.value);
    });
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Add RTL language support

MapLibre GL JS does not automatically display right-to-left languages such as Arabic and Hebrew correctly. Use the Mapbox GL RTL Text plugin to configure settings for RTL languages.

Call the maplibregl.setRTLTextPlugin with the URL of the Mapbox GL RTL Text plugin to configure support for RTL languages.

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    languageSelectElement.addEventListener("change", (e) => {
      setLanguage(e.target.value);
      console.log(e.target.value);
    });

    maplibregl.setRTLTextPlugin('https://unpkg.com/@mapbox/mapbox-gl-rtl-text@0.2.3/mapbox-gl-rtl-text.js');
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