Add a feature layer from a portal item

Before starting this tutorial:

1. You need an ArcGIS Location Platform or ArcGIS Online account.

2. Your system meets the system requirements.

3. The ArcGIS Maps SDK for Qt, version 300.0.0 or later is installed.

4. The Qt 6.8.2 software development framework or later is installed.

Option 1: Develop the code

To start the tutorial, complete the Display a map tutorial. This creates a map to display the Santa Monica Mountains in California using the topographic basemap from the ArcGIS Basemap Styles service The ArcGIS Basemap Styles service, also referred to as the Basemap Styles service, is a location service that provides basemap styles and data for the world. It returns styles as Mapbox styles and web maps, and data as vector tiles and/or map tiles. It supports all of the styles in the ArcGIS Basemap style and Open Basemap style family. An ArcGIS Location Platform or ArcGIS Online account is required to use the service. Learn more .

Open a Qt Creator project

1. Open the project you created by completing the Display a map tutorial.
2. Continue with the following instructions to use an ArcGIS portal item to access and display a feature layer in a map.

Include header files

Your app needs the Portal and PortalItem classes to load an item hosted on ArcGIS Online and display it as a FeatureLayer in the map.

1. In the project, open the Sources folder and open the Display_a_map.cpp file. Add the following four include statements.

   Display-a-map.cpp

   #include "Display_a_map.h"
   #include "Map.h"
   #include "MapTypes.h"
   #include "MapQuickView.h"
   #include "Point.h"
   #include "Viewpoint.h"
   #include "SpatialReference.h"
   #include <QFuture>
   
   #include "Portal.h"
   #include "PortalItem.h"
   #include "FeatureLayer.h"
   #include "LayerListModel.h"

Add the trailheads feature layer to the map

You will connect to ArcGIS Online and access a hosted item (trailheads layer) using its item ID An item ID is a unique identifier representing a single item stored, managed, and accessed in a portal, such as a web map, hosted layer, or file. Learn more . You can then create a FeatureLayer to display the PortalItem in the map.

1. In the setupViewpoint() method, create a Portal instance using the default constructor.

   Display-a-map.cpp

   void Display_a_map::setupViewpoint()
   {
   
     const Point center(-118.80543, 34.02700, SpatialReference::wgs84());
     const Viewpoint viewpoint(center, 100000.0);
     m_mapView->setViewpointAsync(viewpoint);
   
     Portal* portal = new Portal(this);
   
   }

2. Continuing in the setupViewpoint() method, add code to create a PortalItem that references the trailheads item ID on the Portal.

   Display-a-map.cpp

   void Display_a_map::setupViewpoint()
   {
   
     const Point center(-118.80543, 34.02700, SpatialReference::wgs84());
     const Viewpoint viewpoint(center, 100000.0);
     m_mapView->setViewpointAsync(viewpoint);
   
     Portal* portal = new Portal(this);
   
     const QString itemId("2e4b3df6ba4b44969a3bc9827de746b3");
     PortalItem* portalItem = new PortalItem(portal, itemId, this);
   
   }

3. Concluding in the setupViewpoint() method, add code to create a FeatureLayer, using the PortalItem and referencing a serviceLayerId of 0 (zero). Then append this layer to the map’s data layers (operational layers). Save the file.

   Display-a-map.cpp

   void Display_a_map::setupViewpoint()
   {
   
     const Point center(-118.80543, 34.02700, SpatialReference::wgs84());
     const Viewpoint viewpoint(center, 100000.0);
     m_mapView->setViewpointAsync(viewpoint);
   
     Portal* portal = new Portal(this);
   
     const QString itemId("2e4b3df6ba4b44969a3bc9827de746b3");
     PortalItem* portalItem = new PortalItem(portal, itemId, this);
   
     FeatureLayer* trailheadsLayer = new FeatureLayer(portalItem, 0, this);
     m_map->operationalLayers()->append(trailheadsLayer);
   
   }

Set developer credentials

For the final steps of this tutorial, click the tab below that corresponds to the authentication type (API key authentication or User authentication) that you chose when you completed the Display a map tutorial.

Be sure to also provide the same authentication (API key or user authentication Client ID/Redirect URL) that you used for the Display a map tutorial.

ARCGIS_RUNTIME_VERSION = 300.0.0
include($$PWD/arcgisruntime.pri)

# TODO: You need to replace the <path_to_toolkit_repo> with a valid location where the Qt Toolkit
# resides on your system, example: C:/arcgis-maps-sdk-toolkit-qt/uitools/toolkitcpp/toolkitcpp.pri
# This block determines whether you've cloned your toolkit
PATH_TO_TOOLKIT = "<path_to_toolkit_repo>/uitools/toolkitcpp/toolkitcpp.pri"

exists($${PATH_TO_TOOLKIT}) {
  message("Toolkit found")
  DEFINES += TOOLKIT_FOUND

  # include the toolkitcpp.pri, which contains all the toolkit resources
  include($${PATH_TO_TOOLKIT})

  qtHaveModule(webenginequick) {
    QT += webenginequick
  }
} else {
  message("Toolkit not found in provided path. Either set PATH_TO_TOOLKIT or use an API Key")
}

{

#ifdef TOOLKIT_FOUND

    // Define the Redirect URL string obtained when creating the OAuth credentials.
    // TODO: You need to replace the "REDIRECT_URL" with your own valid string,
    // ex: "urn:ietf:wg:oauth:2.0:oob"
    const auto qStringRedirectUrl = QString{"REDIRECT_URL"};

    // Define the URL of the portal to authenticate with.
    const QUrl qUrlPortal = QUrl{"https://www.arcgis.com/"};

    // Define a unique identifier associated with an application registered with the
    // portal that assists with client/server OAuth authentication.
    // TODO: You need to replace the "CLIENT_ID" with your own valid string.
    const QString qStringClientId = QString{"CLIENT_ID"};

    // Create a new OAuth user configuration using: the Url to mapping web service, the Client ID
    // string, and the Redirect Url string.
    auto* oAuthUserConfiguration = new OAuthUserConfiguration(qUrlPortal, qStringClientId,
                                                              qStringRedirectUrl, this);

    // Call the Toolkit's OAuthUserConfigurationManager static `addConfiguration`
    // method to use the OAuth dialog. This will tell the Authenticator to use OAuth for the provided configuration.
    Toolkit::OAuthUserConfigurationManager::addConfiguration(oAuthUserConfiguration);
#endif // TOOLKIT_FOUND

Press Ctrl + R to run the app.

Your app should display a map with the trailheads centered on the Santa Monica Mountains. Double-click, drag, and scroll the mouse wheel over the map view to explore the map.

Option 2: Download the solution

1. Click the Download solution link under Solution and unzip the file to a location on your machine.

2. Open the .pro project file in Qt Creator.

Since the downloaded solution does not contain authentication credentials, you must set up authentication to create the developer credentials and add them to the project.

For the final steps of this tutorial, click the tab below that corresponds to the authentication type (API key authentication or User authentication) that you chose when you completed the Display a map tutorial.

Be sure to also provide the same authentication (API key or user authentication Client ID/Redirect URL) that you used for the Display a map tutorial.

Set developer credentials in the solution

ARCGIS_RUNTIME_VERSION = 300.0.0
include($$PWD/arcgisruntime.pri)

# TODO: You need to replace the <path_to_toolkit_repo> with a valid location where the Qt Toolkit
# resides on your system, example: C:/arcgis-maps-sdk-toolkit-qt/uitools/toolkitcpp/toolkitcpp.pri
# This block determines whether you've cloned your toolkit
PATH_TO_TOOLKIT = "<path_to_toolkit_repo>/uitools/toolkitcpp/toolkitcpp.pri"

exists($${PATH_TO_TOOLKIT}) {
  message("Toolkit found")
  DEFINES += TOOLKIT_FOUND

  # include the toolkitcpp.pri, which contains all the toolkit resources
  include($${PATH_TO_TOOLKIT})

  qtHaveModule(webenginequick) {
    QT += webenginequick
  }
} else {
  message("Toolkit not found in provided path. Either set PATH_TO_TOOLKIT or use an API Key")
}

{

#ifdef TOOLKIT_FOUND

    // Define the Redirect URL string obtained when creating the OAuth credentials.
    // TODO: You need to replace the "REDIRECT_URL" with your own valid string,
    // ex: "urn:ietf:wg:oauth:2.0:oob"
    const auto qStringRedirectUrl = QString{"REDIRECT_URL"};

    // Define the URL of the portal to authenticate with.
    const QUrl qUrlPortal = QUrl{"https://www.arcgis.com/"};

    // Define a unique identifier associated with an application registered with the
    // portal that assists with client/server OAuth authentication.
    // TODO: You need to replace the "CLIENT_ID" with your own valid string.
    const QString qStringClientId = QString{"CLIENT_ID"};

    // Create a new OAuth user configuration using: the Url to mapping web service, the Client ID
    // string, and the Redirect Url string.
    auto* oAuthUserConfiguration = new OAuthUserConfiguration(qUrlPortal, qStringClientId,
                                                              qStringRedirectUrl, this);

    // Call the Toolkit's OAuthUserConfigurationManager static `addConfiguration`
    // method to use the OAuth dialog. This will tell the Authenticator to use OAuth for the provided configuration.
    Toolkit::OAuthUserConfigurationManager::addConfiguration(oAuthUserConfiguration);
#endif // TOOLKIT_FOUND

Run the solution

Press Ctrl + R to run the app.

Your app should display a map with the trailheads centered on the Santa Monica Mountains. Double-click, drag, and scroll the mouse wheel over the map view to explore the map.