Change the basemap language

Learn how to localize basemap place labels using the basemap styles service.

The basemap styles service provides a number of basemap layer styles such as topography, streets, and imagery that you can use in maps. 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 will create a Calcite combobox to switch between different languages to update the Basemap style and app language.

Prerequisites

Steps

Create a new pen

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

Get an access token

You need an access token with the correct privileges to access the location services 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

In CodePen, set esriConfig.apiKey to your access token.

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  var esriConfig = {
    apiKey: "YOUR_ACCESS_TOKEN",
  };

To learn about other ways to get an access token, go to Types of authentication.

Update the map

Update the center and zoom attributes to focus the display on Europe.

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    <arcgis-map basemap="arcgis/topographic" center="13, 46" zoom="4">

      <arcgis-zoom slot="top-left"></arcgis-zoom>

    </arcgis-map>
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Add modules

The request module can be used to request data from a remote server or file. We'll use this module to fetch the available languages from the basemap style API endpoint.

In a new <script> at the bottom of the <body>, use $arcgis.import() to add the request module.

The ArcGIS Maps SDK for JavaScript is available via CDN and npm, but this tutorial is based on CDN. The $arcgis.import global function accepts a module path or array of module paths, and returns a promise that resolves with the requested modules. This function can only be used when working with the CDN; otherwise, use the standard import syntax. To learn more about the SDK's different modules, visit the References page.

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    <script type="module">
      const esriRequest = await $arcgis.import("@arcgis/core/request.js");


    </script>
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Set the current language

Set the current language of the basemap and the lang attribute on the body to Spanish (es). Setting the lang of the application will update the components to use the given language and formatting. For instance, when the locale is set to Spanish, the zoom component tooltip will say Acercar instead of Zoom in.

Set the app's locale to Spanish (es) by setting the lang attribute on the document body.

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  <body lang="es">

    <arcgis-map basemap="arcgis/topographic" center="13, 46" zoom="4">

      <arcgis-zoom slot="top-left"></arcgis-zoom>

    </arcgis-map>

  </body>
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Set the basemap from a style to the arcgis/outdoor basemap style with the language property set to "es". This will display the basemap's place labels in Spanish.

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    <script type="module">
      const esriRequest = await $arcgis.import("@arcgis/core/request.js");


      const viewElement = document.querySelector("arcgis-map");
      viewElement.basemap = {
        style: {
          id: "arcgis/outdoor",
          language: "es", // Spanish language basemap
        },
      };

    </script>
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Get the list of languages available from the basemap styles service and add them to a calcite-combobox component to allow users to select the language of their basemap.

Create a div called basemapLanguage with a calcite-combobox component, placed in the top-right slot of the map. Set selection-mode to single, so only one language can be selected at a time. Add the clear-disabled attribute so that a language is always selected.

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    <arcgis-map basemap="arcgis/topographic" center="13, 46" zoom="4">

      <arcgis-zoom slot="top-left"></arcgis-zoom>

      <div id="basemapLanguage" slot="top-right">
        <calcite-label>Basemap language</calcite-label>
        <calcite-combobox
          id="languageCombobox"
          selection-mode="single"
          clear-disabled></calcite-combobox>
      </div>

    </arcgis-map>
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Within the <style> tags, apply some CSS properties to the basemapLanguage div.

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      #basemapLanguage {
        width: 200px;
        padding: 10px;
        background-color: white;
      }
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Fetch the list of languages available from the /self endpoint for the basemap styles service using the esriRequest method. Specify json as the response type. This will return a json response with a languages property.

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      // update combobox values with languages from rest endpoint
      const basemapStylesEndpoint =
        "https://basemapstyles-api.arcgis.com/arcgis/rest/services/styles/v2/styles/self";
      esriRequest(basemapStylesEndpoint, {
        responseType: "json",
      }).then((response) => {

      });
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From the response data, use the JavaScript forEach method to iterate through each of the languages and add it as a calcite-combobox-item. Set the value to the language code, and the label to the language name. If the language code matches the language of the current basemap, set the item as selected.

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      // update combobox values with languages from rest endpoint
      const basemapStylesEndpoint =
        "https://basemapstyles-api.arcgis.com/arcgis/rest/services/styles/v2/styles/self";
      esriRequest(basemapStylesEndpoint, {
        responseType: "json",
      }).then((response) => {

        const json = response.data;
        // add each language as a combobox item
        json.languages.forEach((language, index) => {
          const comboboxItem = document.createElement("calcite-combobox-item");
          comboboxItem.value = language.code;
          comboboxItem.heading = language.name;
          // if the current basemap language is the same as the combobox item, select it
          comboboxItem.selected = viewElement.basemap.style.language === language.code;
          languageCombobox.appendChild(comboboxItem);
        });

      });
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Create a basemap language function

Create a function that accepts a language code and updates the basemap style formatted with that language.

Define a new function updateBasemapLanguage that accepts a language code.

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      const updateLanguage = (languageCode) => {

      };

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Use the languageCode variable to update the application's language and the language of the basemap style.

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      const updateLanguage = (languageCode) => {

        // update language in html body
        document.body.setAttribute("lang", languageCode);
        // update the basemap language
        viewElement.basemap = {
          style: {
            id: "arcgis/outdoor",
            language: languageCode,
          },
        };

      };

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Update the language on user input

Use the calciteComboboxChange event to recognize when the user has selected a new language.

Add an event listener to watch for changes on the combobox. When the combobox value has changed, call the updateBasemapLanguage function to update the basemap language and app locale.

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      const updateLanguage = (languageCode) => {

        // update language in html body
        document.body.setAttribute("lang", languageCode);
        // update the basemap language
        viewElement.basemap = {
          style: {
            id: "arcgis/outdoor",
            language: languageCode,
          },
        };

      };

      const languageCombobox = document.getElementById("languageCombobox");
      // when the combobox value changes, update the language
      languageCombobox.addEventListener("calciteComboboxChange", () => {
        updateLanguage(languageCombobox.value);
      });
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Run the App

In CodePen, run your code to display the map.

You should be able to use the calcite combobox to update the basemap language and app language.

What's Next?

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