Configure basemap style language

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Sample viewer app

Apply basemap style parameters customization for a basemap, such as displaying all labels in a specific language or displaying every label in their corresponding local language.

screenshot

Use case

When creating an application that’s used in multiple countries, basemaps can reflect the languages and cultures of the users' location. For example, if an application user is in Greece, displaying the labels on a basemap in Greek reflects the local language. Customizing the language setting on the basemap can be controlled by an application user (such as by setting preferences), or implicitly managed within the application logic (by querying the locale of the platform running the application).

How to use the sample

This sample showcases the workflow of configuring basemap style parameters by displaying a basemap with labels in different languages and launches with a Viewpoint set over Bulgaria, Greece and Turkey, as they use three different alphabets: Cyrillic, Greek, and Latin, respectively. By default, the BasemapStyleLanguageStrategy is set to LOCAL which displays all labels in their corresponding local language. This can be changed to GLOBAL, which displays all labels in English. The SpecificLanguage setting sets all labels to a selected language and overrides the BasemapStyleLanguageStrategy settings.

Pan and zoom to navigate the map and see how different labels are displayed in these countries depending on the selected BasemapStyleLanguageStrategy and SpecificLanguage: all English, all Greek, all Bulgarian, all Turkish, or each their own.

How it works

Create a BasemapStyleParameters object.
Configure customisation preferences on the BasemapStyleParameters object, for instance:
- setting the LanguageStrategy to BasemapStyleLanguageStrategy.LOCAL or
- setSpecificLanguage("el") changes the label language to Greek.
The SpecificLanguage always overrides the LanguageStrategy, which means the specific language needs to be set to an empty string in order to use the language strategy.
Create a basemap using a BasemapStyle and the BasemapStyleParameters.
Assign the configured basemap to the Map's basemap property.
To modify the basemap style, for example if you want to change your preferences, repeat the above steps.

Relevant API

Basemap
BasemapStyleLanguageStrategy
BasemapStyleParameters
Map
MapView

About the data

The main data for this sample is the BasemapStyle which include basemaps that support both language localization and global language setting. The supported languages, along with their language code, can be found in the API's documentation.

Sample Code

ConfigureBasemapStyleLanguage.cpp

ConfigureBasemapStyleLanguage.h

ConfigureBasemapStyleLanguage.qml

Use dark colors for code blocksCopy
// [WriteFile Name=ConfigureBasemapStyleLanguage, Category=Maps]
// [Legal]
// Copyright 2024 Esri.

// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0

// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// [Legal]

#ifdef PCH_BUILD
#include "pch.hpp"
#endif // PCH_BUILD

#include "Basemap.h"
#include "BasemapStyleParameters.h"
#include "ConfigureBasemapStyleLanguage.h"
#include "Map.h"
#include "MapQuickView.h"
#include "MapTypes.h"
#include "Point.h"
#include "SpatialReference.h"
#include "Viewpoint.h"

#include <QFuture>

using namespace Esri::ArcGISRuntime;

ConfigureBasemapStyleLanguage::ConfigureBasemapStyleLanguage(QObject* parent /* = nullptr */) :
  QObject(parent),
  m_map(new Map(SpatialReference::webMercator(), this)),
  m_basemapStyleParameters(new BasemapStyleParameters(this))
{
}

ConfigureBasemapStyleLanguage::~ConfigureBasemapStyleLanguage() = default;

void ConfigureBasemapStyleLanguage::init()
{
  // Register the map view for QML
  qmlRegisterType<MapQuickView>("Esri.Samples", 1, 0, "MapView");
  qmlRegisterType<ConfigureBasemapStyleLanguage>("Esri.Samples", 1, 0, "ConfigureBasemapStyleLanguageSample");
}

MapQuickView* ConfigureBasemapStyleLanguage::mapView() const
{
  return m_mapView;
}

// Set the view (created in QML)
void ConfigureBasemapStyleLanguage::setMapView(MapQuickView* mapView)
{
  if (!mapView || mapView == m_mapView)
    return;

  m_mapView = mapView;
  m_mapView->setMap(m_map);

  const Point point(3144804, 4904598);

  // Create a Viewpoint object with the created Point and a scale of 10000000
  const Viewpoint viewpoint(point, 10000000);

  // Set the viewpoint for the mapView
  mapView->setViewpointAsync(viewpoint);

  emit mapViewChanged();
}

// Set new basemap language based on the parameters selected
void ConfigureBasemapStyleLanguage::setNewBasemapLanguage(bool global, const QString& language)
{
  m_basemapStyleParameters->setLanguageStrategy(global ? BasemapStyleLanguageStrategy::Global : BasemapStyleLanguageStrategy::Local);

  // A SpecificLanguage setting overrides the LanguageStrategy settings
  if (language == "none")
  {
    m_basemapStyleParameters->setSpecificLanguage("");
  }
  else if (language == "Bulgarian")
  {
    m_basemapStyleParameters->setSpecificLanguage("bg");
  }
  else if (language == "Greek")
  {
    m_basemapStyleParameters->setSpecificLanguage("el");
  }
  else if (language == "Turkish")
  {
    m_basemapStyleParameters->setSpecificLanguage("tr");
  }

  if (m_basemap)
    m_basemap->deleteLater();

  m_basemap = new Basemap(BasemapStyle::OsmLightGray, m_basemapStyleParameters, this);
  m_map->setBasemap(m_basemap);
}