Workflow: Create an app using a web map (ahead of time)

In this workflow, you will learn how to prepare a web map for offline use, define areas in the map for offline use, then use it to create a partially offline app. This is also known as the ahead-of-time method because you are defining the offline areas in the map ahead of time.

Prerequisites

You need an account for ArcGIS Online or ArcGIS Enterprise to host data for offline use and get an access token. If you need an account, go to Get started.

Steps

1. Prepare the map and data

Create a web map

To create a web map with the Map Viewer, start by setting the basemap layer. Use the Streets vector tile basemap layer.

In your web browser, open the Map Viewer and sign into your ArcGIS account.
In the left panel, click Basemap > Current Basemap > Streets.
In the left panel, click Basemap to close the window.

Set focus to an area of interest

To specify the viewpoint of the map to an area of interest, use the magnifier icon and set the map properties to preserve map scale.

In the bottom right panel, click the magnifier icon.
Type in Santa Monica in the search field and hit enter. This will set your map focus to an area of interest, which, in this case, is the city of Santa Monica, California.
In the left panel, click Map properties.
Under Map view, toggle on the Preserve map scale. This will ensure that the map focus stays on the city of Santa Monica, California, even after you close the web map.

Your web map should look something like this.

Save the web map

Now that you have a web map, you need to save it to your portal.

In the left panel, click Save > Save as. At minimum, you need to provide a title and tags for your web map.
In the left panel, click Share map.
Select Everyone (public). Then, click Save.

Enable web map for offline use

In your web browser, find the item ID at the end of the URL for the web map you just saved.
- For example: 8ab76e9c5352400d87ca3315db9ba08e
In a new browser tab, copy and paste the following URL and insert your item ID. This will return the item page for your web map, where you can configure it for offline use.
- https://www.arcgis.com/home/item.html?id=<ITEM_ID>
- For example: https://www.arcgis.com/home/item.html?id=8ab76e9c5352400d87ca3315db9ba08e
Click Settings on the top bar of the item page.
Scroll down to the Offline menu.
If you don't see the Offline enabled icon at the top right corner, click Check Compatibility and turn on Offline.
Optionally, you can also manage advanced offline settings for your web map by clicking Options. These settings allow you to choose what data or updates mobile devices get and use a tile package for your offline basemap.

Under Features and attachments, you can configure download behaviors for both editable and read-only features. Adjusting how attachments and features are delivered can reduce the time it takes to synchronize edits, especially in areas of poor connectivity, as well as the amount of cellular data used.
Under Basemap and tile package, you can choose which basemap you want to use on your map. If you choose to use a local tile package, you will provide the filename of the package on your device. If you choose to use a tile package from your organization, you will browse a tile package from your ArcGIS organization.
Click Save. Your web map is enabled for offline use now.

Draw offline map areas

Now, you are going to define areas in your web map that you want to take offline, also known as offline map areas or preplanned map areas_.

Under Offline Map Areas, click Manage Offline Areas.
In the left panel, click Create offline area.
Draw an offline area on the map. You have two options to do this:
- To draw a box around the area to take offline, click the Sketch rectangular map area button and draw a box on the map.
- To draw a polygon to define the area you need to take offline, click the Sketch polygon map area button and draw the polygon on the map.
Tip
If you want to sketch a polygon rather than a rectangle, the map's basemap must be an ArcGIS Online hosted tile layer or a tile layer from an ArcGIS Enterprise 10.7 or later portal.

Manage offline map area settings

After defining your offline map areas, you can configure settings such as name, level of detail, and packaging schedule. Then, you will save the offline map area and an offline map package will be generated.

In the Name field in the left panel, type a descriptive name for the offline map area.
Open the Level of detail setting to change the quality and resolution of the downloaded raster or vector tile layers. You can move the slider to the right for more detail or to the left for less detail. Make sure that the small triangle icon is included in the scope of your slider.

Set a level of detail that is appropriate for the offline map area you create. If the level of detail is too great (for example, you set the level of detail to Streets but your offline map area is the size of Spain), you'll receive a warning indicating you must either reduce the offline map area or decrease the level of detail.
Open the Packaging schedule section to set the interval and time that you want the offline map area packages to be refreshed to capture changes to feature layer data. If you don't want to set an automatic refresh schedule, select Never from the drop-down menu.

Tip
Scheduled refreshes do not apply to tile layers. You must manually refresh tile layer packages as needed.
Open the Optimizations section to create offline map area packages for read-only use. Then, switch on the Enable packaged updates toggle button. Read-only packages are created based on the schedule you set in the previous step.
Click Save.

The new offline map area appears in the Offline map areas list with a badge indicating the area is being packaged. Packaging can take several seconds or minutes, depending on the size of the data being packaged.
Packaging will fail if the size of the offline map area, when packaged, is larger than 2.5 GB. If packaging fails, try sketching a smaller area to include in the offline map package. If the map contains feature layers that have attachments, you can exclude attachments from the offline package to decrease the package size. If the map includes tile layers, you can decrease the size of the offline map area by adjusting the level of detail to include less detail.
To create more offline areas for this map, click Create offline area and repeat the previous steps starting from Draw offline map areas. You can create up to 16 offline map areas per web map.

2. Build the app

Setup offline app

Install and setup the ArcGIS Maps SDK for .NET on your development machine. Make sure you fulfill the SDK's system requirements.
Follow the Display a map tutorial or download the completed solution to get a starter code for this workflow.
Open the .sln file in Visual Studio.

The Visual Studio solution, project, and the namespace for all classes currently use the name DisplayAMap. Follow the steps below if you prefer the name to reflect the current tutorial. These steps are not required, your code will still work if you keep the original name.
Update the name for the solution and the project.
- In Visual Studio, in the Solution Explorer, right-click the solution name and choose Rename. Provide the new name for your solution.
- In the Solution Explorer, right-click the project name and choose Rename. Provide the new name for your project.
Rename the namespace used by classes in the project.
- In the Solution Explorer, expand the project node.
- Double-click MapViewModel.cs in the Solution Explorer to open the file.
- In the MapViewModel class, double-click the namespace name (DisplayAMap) to select it, and then right-click and choose Rename....
- Provide the new name for the namespace.
- Click Apply in the Rename: DisplayAMap window that appears in the upper-right of the code window. This will rename the namespace throughout your project.
Build the project.
- Choose Build > Build solution (or press F6).

Install and setup the ArcGIS Maps SDK for Kotlin on your development machine. Make sure you fulfill the SDK's system requirements.
Complete the Display a map tutorial. Or download and unzip the Display a map solution in a new folder.
Modify the old project for use in this new tutorial. Expand More info for instructions.
1. On your file system, delete the .idea folder, if present, at the top level of your project.
2. In the Android tool window, open app > res > values > strings.xml.
  
  In the <string name="app_name"> element, change the text content to a title that suits your app objective.
3. In the Android tool window, open Gradle Scripts > settings.gradle.kts.
  
  Change the value of rootProject.name to a title that suits your app objective.
4. The UI theme composable in Display a map tutorial was DisplayAMapTheme. Rename the theme composable throughout the tutorial by refactoring DisplayAMapTheme.
  
  Right-click the function name DisplayAMapTheme and select Refactor -> Rename. Replace the name with a name that suits your app objective.
5. Click File > Sync Project with Gradle files. Android Studio will recognize your changes and create a new .idea folder.

Download and display the offline map

In the Visual Studio > Solution Explorer, double-click MapViewModel.cs to open the file.

The project uses the Model-View-ViewModel (MVVM) design pattern to separate the application logic (view model) from the user interface (view). MapViewModel.cs contains the view model class for the application, called MapViewModel. See the Microsoft documentation for more information about the Model-View-ViewModel pattern.

Add additional required using statements at the top of the class.

MapViewModel.cs
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Add line.Add line.Add line.
using System;
using System.Collections.Generic;
using Esri.ArcGISRuntime.Portal;
using System.Text;
using System.Threading.Tasks;
using System.ComponentModel;
using System.Runtime.CompilerServices;

using System.Linq;
using Esri.ArcGISRuntime.Mapping;
using Esri.ArcGISRuntime.Tasks.Offline;

Create an empty global variable _downloadLocation to store the path to the downloaded map area later.

MapViewModel.cs
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Add line.        private string _downloadLocation;

        private Map? _map;
        public Map? Map
        {
            get { return _map; }
            set
            {
                _map = value;
                OnPropertyChanged();
            }
        }

Modify the SetupMap function signature to private async returning a Task.

MapViewModel.cs
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Change lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange lineChange line        private async Task GetOfflinePreplannedMap()
        {
            var portal = await ArcGISPortal.CreateAsync();
            var portalItem = await PortalItem.CreateAsync(portal, "YOUR_ITEM_ID"); // Replace with your web map ID
            var map = new Map(portalItem);

            OfflineMapTask offlineMapTask = await OfflineMapTask.CreateAsync(map);
            IReadOnlyList<PreplannedMapArea> availableAreas = await offlineMapTask.GetPreplannedMapAreasAsync();

            if (availableAreas?.FirstOrDefault() is PreplannedMapArea area)
            {
                DownloadPreplannedOfflineMapParameters downloadParameters = await offlineMapTask.CreateDefaultDownloadPreplannedOfflineMapParametersAsync(area);

                string documentsFolder = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
                _downloadLocation = System.IO.Path.Combine(documentsFolder, "OfflineMap");

                DownloadPreplannedOfflineMapJob job = offlineMapTask.DownloadPreplannedOfflineMap(downloadParameters, _downloadLocation);
                DownloadPreplannedOfflineMapResult result = await job.GetResultAsync();

                if (result?.OfflineMap is Map offlineMap)
                {
                    this.Map = offlineMap;
                }
            }
        }

Remove the Map initializer from the SetupMap function. Because the map area will be downloaded from the web map, this is no longer needed.

MapViewModel.cs
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        private async Task GetOfflinePreplannedMap()
        {
            var portal = await ArcGISPortal.CreateAsync();
            var portalItem = await PortalItem.CreateAsync(portal, "YOUR_ITEM_ID"); // Replace with your web map ID
            var map = new Map(portalItem);

            OfflineMapTask offlineMapTask = await OfflineMapTask.CreateAsync(map);
            IReadOnlyList<PreplannedMapArea> availableAreas = await offlineMapTask.GetPreplannedMapAreasAsync();

            if (availableAreas?.FirstOrDefault() is PreplannedMapArea area)
            {
                DownloadPreplannedOfflineMapParameters downloadParameters = await offlineMapTask.CreateDefaultDownloadPreplannedOfflineMapParametersAsync(area);

                string documentsFolder = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
                _downloadLocation = System.IO.Path.Combine(documentsFolder, "OfflineMap");

                DownloadPreplannedOfflineMapJob job = offlineMapTask.DownloadPreplannedOfflineMap(downloadParameters, _downloadLocation);
                DownloadPreplannedOfflineMapResult result = await job.GetResultAsync();

                if (result?.OfflineMap is Map offlineMap)
                {
                    this.Map = offlineMap;
                }
            }
        }

Inside MainWindow.xaml.cs, remove the viewpoint configuration.

MainWindow.xaml.cs
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Remove lineRemove line        public MainWindow()
        {
            InitializeComponent();

            MapPoint mapCenterPoint = new MapPoint(-118.805, 34.027, SpatialReferences.Wgs84);
            MainMapView.SetViewpoint(new Viewpoint(mapCenterPoint, 100000));

        }

Get the web map item ID from your ArcGIS Online, for example 8ab76e9c5352400d87ca3315db9ba08e.

Create a Map from the web map using its item ID.

MapViewModel.cs
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        private async Task GetOfflinePreplannedMap()
        {
            var portal = await ArcGISPortal.CreateAsync();
            var portalItem = await PortalItem.CreateAsync(portal, "YOUR_ITEM_ID"); // Replace with your web map ID
            var map = new Map(portalItem);

            OfflineMapTask offlineMapTask = await OfflineMapTask.CreateAsync(map);
            IReadOnlyList<PreplannedMapArea> availableAreas = await offlineMapTask.GetPreplannedMapAreasAsync();

            if (availableAreas?.FirstOrDefault() is PreplannedMapArea area)
            {
                DownloadPreplannedOfflineMapParameters downloadParameters = await offlineMapTask.CreateDefaultDownloadPreplannedOfflineMapParametersAsync(area);

                string documentsFolder = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
                _downloadLocation = System.IO.Path.Combine(documentsFolder, "OfflineMap");

                DownloadPreplannedOfflineMapJob job = offlineMapTask.DownloadPreplannedOfflineMap(downloadParameters, _downloadLocation);
                DownloadPreplannedOfflineMapResult result = await job.GetResultAsync();

                if (result?.OfflineMap is Map offlineMap)
                {
                    this.Map = offlineMap;
                }
            }
        }

Create an OfflineMapTask referencing the web map. This task object reads the offline properties of the web map and manages downloading an offline map from it.

MapViewModel.cs
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        private async Task GetOfflinePreplannedMap()
        {
            var portal = await ArcGISPortal.CreateAsync();
            var portalItem = await PortalItem.CreateAsync(portal, "YOUR_ITEM_ID"); // Replace with your web map ID
            var map = new Map(portalItem);

            OfflineMapTask offlineMapTask = await OfflineMapTask.CreateAsync(map);
            IReadOnlyList<PreplannedMapArea> availableAreas = await offlineMapTask.GetPreplannedMapAreasAsync();

            if (availableAreas?.FirstOrDefault() is PreplannedMapArea area)
            {
                DownloadPreplannedOfflineMapParameters downloadParameters = await offlineMapTask.CreateDefaultDownloadPreplannedOfflineMapParametersAsync(area);

                string documentsFolder = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
                _downloadLocation = System.IO.Path.Combine(documentsFolder, "OfflineMap");

                DownloadPreplannedOfflineMapJob job = offlineMapTask.DownloadPreplannedOfflineMap(downloadParameters, _downloadLocation);
                DownloadPreplannedOfflineMapResult result = await job.GetResultAsync();

                if (result?.OfflineMap is Map offlineMap)
                {
                    this.Map = offlineMap;
                }
            }
        }

Use the OfflineMapTask to list any available ahead-of-time offline maps. In the ArcGIS Maps SDKs for Native Apps the ahead-of-time offline map areas are referred to as preplanned areas.

MapViewModel.cs
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        private async Task GetOfflinePreplannedMap()
        {
            var portal = await ArcGISPortal.CreateAsync();
            var portalItem = await PortalItem.CreateAsync(portal, "YOUR_ITEM_ID"); // Replace with your web map ID
            var map = new Map(portalItem);

            OfflineMapTask offlineMapTask = await OfflineMapTask.CreateAsync(map);
            IReadOnlyList<PreplannedMapArea> availableAreas = await offlineMapTask.GetPreplannedMapAreasAsync();

            if (availableAreas?.FirstOrDefault() is PreplannedMapArea area)
            {
                DownloadPreplannedOfflineMapParameters downloadParameters = await offlineMapTask.CreateDefaultDownloadPreplannedOfflineMapParametersAsync(area);

                string documentsFolder = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
                _downloadLocation = System.IO.Path.Combine(documentsFolder, "OfflineMap");

                DownloadPreplannedOfflineMapJob job = offlineMapTask.DownloadPreplannedOfflineMap(downloadParameters, _downloadLocation);
                DownloadPreplannedOfflineMapResult result = await job.GetResultAsync();

                if (result?.OfflineMap is Map offlineMap)
                {
                    this.Map = offlineMap;
                }
            }
        }

Get a set of default DownloadPreplannedOfflineMapParameters. These parameters describe how the owner of the web map configured the offline map to be downloaded by default. You can modify the parameters to fine tune the downloaded offline map.

MapViewModel.cs
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        private async Task GetOfflinePreplannedMap()
        {
            var portal = await ArcGISPortal.CreateAsync();
            var portalItem = await PortalItem.CreateAsync(portal, "YOUR_ITEM_ID"); // Replace with your web map ID
            var map = new Map(portalItem);

            OfflineMapTask offlineMapTask = await OfflineMapTask.CreateAsync(map);
            IReadOnlyList<PreplannedMapArea> availableAreas = await offlineMapTask.GetPreplannedMapAreasAsync();

            if (availableAreas?.FirstOrDefault() is PreplannedMapArea area)
            {
                DownloadPreplannedOfflineMapParameters downloadParameters = await offlineMapTask.CreateDefaultDownloadPreplannedOfflineMapParametersAsync(area);

                string documentsFolder = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
                _downloadLocation = System.IO.Path.Combine(documentsFolder, "OfflineMap");

                DownloadPreplannedOfflineMapJob job = offlineMapTask.DownloadPreplannedOfflineMap(downloadParameters, _downloadLocation);
                DownloadPreplannedOfflineMapResult result = await job.GetResultAsync();

                if (result?.OfflineMap is Map offlineMap)
                {
                    this.Map = offlineMap;
                }
            }
        }

Define a path to store the downloaded map area and store it in the global variable _downloadLocation.

MapViewModel.cs
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        private async Task GetOfflinePreplannedMap()
        {
            var portal = await ArcGISPortal.CreateAsync();
            var portalItem = await PortalItem.CreateAsync(portal, "YOUR_ITEM_ID"); // Replace with your web map ID
            var map = new Map(portalItem);

            OfflineMapTask offlineMapTask = await OfflineMapTask.CreateAsync(map);
            IReadOnlyList<PreplannedMapArea> availableAreas = await offlineMapTask.GetPreplannedMapAreasAsync();

            if (availableAreas?.FirstOrDefault() is PreplannedMapArea area)
            {
                DownloadPreplannedOfflineMapParameters downloadParameters = await offlineMapTask.CreateDefaultDownloadPreplannedOfflineMapParametersAsync(area);

                string documentsFolder = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
                _downloadLocation = System.IO.Path.Combine(documentsFolder, "OfflineMap");

                DownloadPreplannedOfflineMapJob job = offlineMapTask.DownloadPreplannedOfflineMap(downloadParameters, _downloadLocation);
                DownloadPreplannedOfflineMapResult result = await job.GetResultAsync();

                if (result?.OfflineMap is Map offlineMap)
                {
                    this.Map = offlineMap;
                }
            }
        }

Use the parameters to create a DownloadPreplannedOfflineMapJob to download the offline map, specifying the download location.

MapViewModel.cs
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        private async Task GetOfflinePreplannedMap()
        {
            var portal = await ArcGISPortal.CreateAsync();
            var portalItem = await PortalItem.CreateAsync(portal, "YOUR_ITEM_ID"); // Replace with your web map ID
            var map = new Map(portalItem);

            OfflineMapTask offlineMapTask = await OfflineMapTask.CreateAsync(map);
            IReadOnlyList<PreplannedMapArea> availableAreas = await offlineMapTask.GetPreplannedMapAreasAsync();

            if (availableAreas?.FirstOrDefault() is PreplannedMapArea area)
            {
                DownloadPreplannedOfflineMapParameters downloadParameters = await offlineMapTask.CreateDefaultDownloadPreplannedOfflineMapParametersAsync(area);

                string documentsFolder = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
                _downloadLocation = System.IO.Path.Combine(documentsFolder, "OfflineMap");

                DownloadPreplannedOfflineMapJob job = offlineMapTask.DownloadPreplannedOfflineMap(downloadParameters, _downloadLocation);
                DownloadPreplannedOfflineMapResult result = await job.GetResultAsync();

                if (result?.OfflineMap is Map offlineMap)
                {
                    this.Map = offlineMap;
                }
            }
        }

Start the job and wait for it to complete, returning a Map that is ready for use.

MapViewModel.cs
Expand
Use dark colors for code blocks
        private async Task GetOfflinePreplannedMap()
        {
            var portal = await ArcGISPortal.CreateAsync();
            var portalItem = await PortalItem.CreateAsync(portal, "YOUR_ITEM_ID"); // Replace with your web map ID
            var map = new Map(portalItem);

            OfflineMapTask offlineMapTask = await OfflineMapTask.CreateAsync(map);
            IReadOnlyList<PreplannedMapArea> availableAreas = await offlineMapTask.GetPreplannedMapAreasAsync();

            if (availableAreas?.FirstOrDefault() is PreplannedMapArea area)
            {
                DownloadPreplannedOfflineMapParameters downloadParameters = await offlineMapTask.CreateDefaultDownloadPreplannedOfflineMapParametersAsync(area);

                string documentsFolder = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
                _downloadLocation = System.IO.Path.Combine(documentsFolder, "OfflineMap");

                DownloadPreplannedOfflineMapJob job = offlineMapTask.DownloadPreplannedOfflineMap(downloadParameters, _downloadLocation);
                DownloadPreplannedOfflineMapResult result = await job.GetResultAsync();

                if (result?.OfflineMap is Map offlineMap)
                {
                    this.Map = offlineMap;
                }
            }
        }
Expand

Click Debug > Start Debugging (or press F5 on the keyboard) to run the app.

In the Android tool window, open app > kotlin+java > com.example.app > screens > MainScreen.kt. Expand the code block below, and replace the existing import statements in your project with the imports needed for this tutorial.

MainScreen.kt
Expand
Use dark colors for code blocks
import com.arcgismaps.geometry.Point
import com.arcgismaps.geometry.SpatialReference
import com.arcgismaps.mapping.ArcGISMap
import com.arcgismaps.mapping.BasemapStyle
import com.arcgismaps.mapping.MobileMapPackage
import com.arcgismaps.mapping.PortalItem
import com.arcgismaps.mapping.Viewpoint
import com.arcgismaps.portal.Portal
import com.arcgismaps.tasks.offlinemaptask.OfflineMapTask
import com.arcgismaps.toolkit.geoviewcompose.MapView
Expand

Delete code from the Display a map tutorial that will not be used in this workflow.

Display a Map tutorial
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@Composable
fun MainScreen() {
    val map = remember {
        createMap()
    }
         Scaffold(
        topBar = { TopAppBar(title = { Text(text = stringResource(id = R.string.app_name)) }) }
    ) {
        MapView(
            modifier = Modifier.fillMaxSize().padding(it),
            arcGISMap = map
        )
    }
}

fun createMap(): ArcGISMap {
    return ArcGISMap(BasemapStyle.ArcGISTopographic).apply {
        initialViewpoint = Viewpoint(
            latitude = 34.0270,
            longitude = -118.8050,
            scale = 72000.0
        )
    }
}

Create a MapViewModel class. Inside it, create the properties shown in the code below.

map, which is initialized using the by keyword and a mutable state of ArcGISMap. The initial viewpoint is centered on an inland area of Santa Monica.
context for the application context.
downloadLocation to hold the path where the downloaded map will be stored on the file system of your device.
downloadDirectory, which creates a directory using the download location and deletes the contents, if any, of the directory.
TAG to pass to the logging functions.

MapViewModel
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class MapViewModel(
    private val application: Application,
    private val coroutineScope: CoroutineScope,
): AndroidViewModel(application) {
    var map by mutableStateOf(ArcGISMap(BasemapStyle.ArcGISStreets).apply {
        initialViewpoint = Viewpoint(
            Point(
                y = 34.0200,
                x = -118.4685,
                spatialReference = SpatialReference.wgs84(),
            ),
            scale = 36_111.909643
        )
    })

    val context = application.applicationContext

    private val localPathForOfflineMap by lazy {
        context.getExternalFilesDir(null)?.path + File.separator + "offlineMapPreplanned"
    }

    // Use the download path to create a directory. If the directory already exists, clear its contents.
    val localDirectoryForOfflineMap = File(localPathForOfflineMap).apply {
        // ensure the directory is empty before starting job
        if (isDirectory && exists()) {
            deleteRecursively()
        }
    }

    private val TAG = this.javaClass.name

    }

}

In MainScreen, create the variables shown below. Note that the mapViewModel variable instantiates the MapViewModelclass.

MainScreen
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@Composable
fun MainScreen() {

    val application = LocalContext.current.applicationContext as Application
    val coroutineScope = rememberCoroutineScope()

    val mapViewModel = remember { MapViewModel(application, coroutineScope) }


}

In MainScreen, call Scaffold, passing a top bar that displays the name of the app. Inside the content block, call Column, which will hold the map view and three buttons.

MainScreen
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@Composable
fun MainScreen() {

    val application = LocalContext.current.applicationContext as Application
    val coroutineScope = rememberCoroutineScope()

    val mapViewModel = remember { MapViewModel(application, coroutineScope) }


    Scaffold(
        topBar = { TopAppBar(title = { Text(text = stringResource(id = R.string.app_name)) }) }
    ) {

        Column(
            modifier = Modifier
                .fillMaxSize()
                .padding(it)
        ) {

        }
    }

}

Inside the content block for Column, call MapView and pass in the map from the map view model.

MainScreen
Use dark colors for code blocks
    Scaffold(
        topBar = { TopAppBar(title = { Text(text = stringResource(id = R.string.app_name)) }) }
    ) {

        Column(
            modifier = Modifier
                .fillMaxSize()
                .padding(it)
        ) {

            MapView(
                modifier = Modifier
                    .fillMaxSize()
                    .weight(1f),
                arcGISMap = mapViewModel.map,
            )

        }
    }

Add two buttons and call the appropriate map view model functions in the onClick callback. We will code those two functions in the rest of this workflow.

MainScreen
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            MapView(
                modifier = Modifier
                    .fillMaxSize()
                    .weight(1f),
                arcGISMap = mapViewModel.map,
            )

            Button(
                onClick = {
                    coroutineScope.launch {
                        mapViewModel.downloadOfflineMapArea()
                    }
                }
            ) {
                Text(text = "Download preplanned offline map area")
            }

            Button(
                onClick = {
                    coroutineScope.launch {
                        mapViewModel.accessOfflineMap()
                    }
                }
            ) {
                Text(text= "Access offline map from local file")
            }

        }
    }

}

The first button will download an area of interest from the Santa Monica web map.

Get the web map item ID from your ArcGIS Online, e.g. 8ab76e9c5352400d87ca3315db9ba08e.

In the MapViewModel class, create a suspend function named downloadOfflineMapArea(). Inside the function, create the variables shown in the code below.

An arcgis.com Portal.
A PortalItem with portal and the item ID.
An OfflineMapTask with the portal item.

MapViewModel
Expand
Use dark colors for code blocks
    suspend fun downloadOfflineMapArea() {
        val portal = Portal(
            url = "https://www.arcgis.com",
            connection = Portal.Connection.Anonymous
        )

        val portalItem = PortalItem(
            portal = portal,
            itemId = "YOUR_ITEM_ID" // Replace with your web map ID.
        )

        val offlineMapTask = OfflineMapTask(portalItem)

Expand

Download a list of preplanned map areas from the Santa Monica web map. And get the first preplanned map area.

MapViewModel
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        val offlineMapTask = OfflineMapTask(portalItem)

        coroutineScope.launch {
            val preplannedMapAreas = offlineMapTask.getPreplannedMapAreas().getOrElse { error ->
                return@launch showMessage(context, "Failed to get preplanned map areas: ${error.message}")
            }

            val selectedArea = preplannedMapAreas.first()

Create default parameters for downloading a preplanned offline map area to the file system of your device.

MapViewModel
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            val selectedArea = preplannedMapAreas.first()

            val params = offlineMapTask.createDefaultDownloadPreplannedOfflineMapParameters(selectedArea).getOrElse { error ->
                return@launch showMessage(context, "No default parameters for download preplanned offline map were created: ${error.message}")
            }

Create a job that will download the preplanned offline map area.

Call createGenerateOfflineMapJob and pass the default parameters and the path of the download directory.
In a coroutine scope, set up logging for the progress of the job.
Start the job.

MainViewModel
Use dark colors for code blocks
            val params = offlineMapTask.createDefaultDownloadPreplannedOfflineMapParameters(selectedArea).getOrElse { error ->
                return@launch showMessage(context, "No default parameters for download preplanned offline map were created: ${error.message}")
            }

            // Create a job with DownloadPreplannedOfflineMapParameters and a download directory path
            val downloadPreplannedOfflineMapJob = offlineMapTask.createDownloadPreplannedOfflineMapJob(
                parameters = params,
                downloadDirectoryPath = localDirectoryForOfflineMap.path.toString()
            )

            coroutineScope.launch {
                downloadPreplannedOfflineMapJob.progress.collect { progress ->
                    Log.i(TAG, "Downloading preplanned offline map. Job progress: $progress%")
                }
            }

            downloadPreplannedOfflineMapJob.start()

From the result of the download preplanned offline map job, get the downloaded offline map. Assign it to the map property of MapViewModel.

MapViewModel
Expand
Use dark colors for code blocks
            val jobResult = downloadPreplannedOfflineMapJob.result().getOrElse { error ->
                return@launch showMessage(context, "Download preplanned offline map job failed: ${error.message}")
            }
            map = jobResult.offlineMap

        }

    }

}

(Optional) The code in this workflow displays messages to the user and logs activity in Logcat. Here is a possible implementation.

MapViewModel
Expand
Use dark colors for code blocks
    private fun showMessage(context: Context, message: String) {
        Toast.makeText(context, message, Toast.LENGTH_LONG).show()
        Log.i(TAG, message)
    }
Expand

Click Run > Run > app to run the app.

Initially, you should see the web map centered centered on an inland area on Santa Monica, CA.

Click the Download preplanned offline map area button. The download might take from a few seconds to a few minutes, depending on your internet connection and the load on the server.

Tip
Check Logcat in Android Studio to track progress of the download.

After the offline map area is downloaded to the Android device, you will see an area of San Monica near the beach, zoomed in closer than the original view point.

In Xcode, in the Project Navigator, click ContentView.swift.

Create a Model and reference it from the View.

ContentView.swift
Use dark colors for code blocks
Add line.Add line.Add line.Add line.private class Model: ObservableObject {

}

struct ContentView: View {

    @StateObject private var model = Model()

    @State private var map = {
        let map = Map(basemapStyle: .arcGISTopographic)
        map.initialViewpoint = Viewpoint(latitude: 34.02700, longitude: -118.80500, scale: 72_000)
        return map
    }()

    var body: some View {

    }
}

Move map to Model and create a MapView with it. Change the Viewpoint of the map to a latitude of 34.0200, a longitude of -118.4685, and a scale of 36_111.909643.

ContentView.swift
Use dark colors for code blocks
Change lineChange lineChange lineChange lineChange lineRemove lineRemove lineRemove lineRemove lineRemove lineChange lineprivate class Model: ObservableObject {

    var map = {
        let map = Map(basemapStyle: .arcGISTopographic)
        map.initialViewpoint = Viewpoint(latitude: 34.0200, longitude: -118.4685, scale: 36_111.909643)
        return map
    }()

}

struct ContentView: View {

    @StateObject private var model = Model()

    @State private var map = {
        let map = Map(basemapStyle: .arcGISTopographic)
        map.initialViewpoint = Viewpoint(latitude: 34.02700, longitude: -118.80500, scale: 72_000)
        return map
    }()

    var body: some View {

        MapView(map: model.map)

    }
}

Create a function called runOfflineMapTask which accepts a file path as a parameter for storing the downloaded offline map.

ContentView.swift
Use dark colors for code blocks
Add line.Add line.Add line.private class Model: ObservableObject {

    var map = {
        let map = Map(basemapStyle: .arcGISTopographic)
        map.initialViewpoint = Viewpoint(latitude: 34.0200, longitude: -118.4685, scale: 36_111.909643)
        return map
    }()

    func runOfflineMapTask(offlineMapURL: URL) async throws {

    }

}

Create a portal item representing the web map you just created, e.g. 8ab76e9c5352400d87ca3315db9ba08e.

ContentView.swift
Use dark colors for code blocks
Add line.Add line.Add line.Add line.    private let santaMonicaWebMap = PortalItem(
        portal: .arcGISOnline(connection: .anonymous),
        id: PortalItem.ID("YOUR_ITEM_ID")! // Replace with your web map ID
    )

Inside the function, create an OfflineMapTask referencing the portal item variable. This task object reads the offline properties of the web map and manages downloading an offline map from it.

ContentView.swift
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Add line.    func runOfflineMapTask(offlineMapURL: URL) async throws {

        let offlineMapTask = OfflineMapTask(portalItem: santaMonicaWebMap)

    }

Use the OfflineMapTask to list any available ahead-of-time offline maps. In the ArcGIS Maps SDKs for Native Apps, the ahead-of-time offline map areas are referred to as preplanned areas.

ContentView.swift
Use dark colors for code blocks
Add line.Add line.    func runOfflineMapTask(offlineMapURL: URL) async throws {

        let offlineMapTask = OfflineMapTask(portalItem: santaMonicaWebMap)

        let areas = try await offlineMapTask.preplannedMapAreas
        guard let area = areas.first else { return }

    }

Get a set of default Download Preplanned Offline Map Parameters. These parameters describe how the owner of the web map configured the offline map to be downloaded by default. You can modify the parameters to fine tune the downloaded offline map.

Options include whether to include the basemap or use one that has already been downloaded, whether to opt into update packages, and whether to disable offline editing even if the source web map supports editing.

ContentView.swift
Use dark colors for code blocks
Add line.    func runOfflineMapTask(offlineMapURL: URL) async throws {

        let offlineMapTask = OfflineMapTask(portalItem: santaMonicaWebMap)

        let areas = try await offlineMapTask.preplannedMapAreas
        guard let area = areas.first else { return }

        let parameters = try await offlineMapTask.makeDefaultDownloadPreplannedOfflineMapParameters(preplannedMapArea: area)

    }

Use the parameters to create a Download Preplanned Offline Map Job to download the offline map, specifying the download location.

ContentView.swift
Use dark colors for code blocks
Add line.    func runOfflineMapTask(offlineMapURL: URL) async throws {

        let offlineMapTask = OfflineMapTask(portalItem: santaMonicaWebMap)

        let areas = try await offlineMapTask.preplannedMapAreas
        guard let area = areas.first else { return }

        let parameters = try await offlineMapTask.makeDefaultDownloadPreplannedOfflineMapParameters(preplannedMapArea: area)

        let job = offlineMapTask.makeDownloadPreplannedOfflineMapJob(parameters: parameters, downloadDirectory: offlineMapURL)

    }

Start the job and wait for it to complete, returning a map, which is ready for use.

ContentView.swift
Expand
Use dark colors for code blocks
Add line.Add line.Add line.    func runOfflineMapTask(offlineMapURL: URL) async throws {

        let offlineMapTask = OfflineMapTask(portalItem: santaMonicaWebMap)

        let areas = try await offlineMapTask.preplannedMapAreas
        guard let area = areas.first else { return }

        let parameters = try await offlineMapTask.makeDefaultDownloadPreplannedOfflineMapParameters(preplannedMapArea: area)

        let job = offlineMapTask.makeDownloadPreplannedOfflineMapJob(parameters: parameters, downloadDirectory: offlineMapURL)

        job.start()
        let output = try await job.output
        map = output.offlineMap

    }
Expand

The function is now ready to be called to download an offline map area. You can trigger this function from a button click or from the main function.

In Projects, double-click Headers > Display_an_offline_map.h to open the file. Add the following classes to the header file.

Display_an_offline_map.h
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Add line.Add line.Add line.Add line.class Map;
class MapQuickView;

class PortalItem;
class OfflineMapTask;
class PreplannedMapArea;

Add the downloadPreplannedMapArea function declaration and member variables m_portalItem, m_offlineMapTask, and m_preplannedMapArea. Save and close the file.

Display_an_offline_map.h
Use dark colors for code blocks
Add line.Add line.Add line.Add line.Add line.Add line.private:
    Esri::ArcGISRuntime::MapQuickView* mapView() const;
    void setMapView(Esri::ArcGISRuntime::MapQuickView* mapView);

    Esri::ArcGISRuntime::Map* m_map = nullptr;
    Esri::ArcGISRuntime::MapQuickView* m_mapView = nullptr;

    void downloadPreplannedMapArea();

    Esri::ArcGISRuntime::PortalItem* m_portalItem = nullptr;
    Esri::ArcGISRuntime::OfflineMapTask* m_offlineMapTask = nullptr;

    Esri::ArcGISRuntime::PreplannedMapArea* m_preplannedMapArea;

};

In Projects, double-click Sources > Display_an_offline_map.cpp to open the file. Remove the #include statement for MapTypes.h because the map will be provided by the offline map.

Display_an_offline_map.cpp
Use dark colors for code blocks
Remove line#include "Display_an_offline_map.h"
#include "Map.h"

#include "MapTypes.h"

#include "MapQuickView.h"

Add the following #include statements. These classes are needed for this application.

Display_an_offline_map.cpp
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Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.#include "Display_an_offline_map.h"
#include "Map.h"

#include "MapQuickView.h"

#include <QFuture>
#include <QStandardPaths>
#include <QDir>
#include "Error.h"
#include "Portal.h"
#include "PortalItem.h"
#include "PreplannedMapArea.h"
#include "OfflineMapTask.h"
#include "MobileMapPackage.h"
#include "DownloadPreplannedOfflineMapParameters.h"
#include "DownloadPreplannedOfflineMapJob.h"
#include "DownloadPreplannedOfflineMapResult.h"

Delete the comma after QObject(parent) and remove the Map from the constructor.

Display_an_offline_map.cpp
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Remove lineusing namespace Esri::ArcGISRuntime;

Display_an_mmpk::Display_an_mmpk(QObject* parent /* = nullptr */):

    QObject(parent),

    m_map(new Map(BasemapStyle::ArcGISStreets, this))

Get the web map item ID from your ArcGIS Online, e.g. 8ab76e9c5352400d87ca3315db9ba08e

Instantiate a Portal and from that, a PortalItem using the web map item ID. Use that to create a new Map. Then create a new OfflineMapTask referencing that portal item.

Display_an_offline_map.cpp
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Add line.Add line.Add line.Add line.
Display_an_offline_map::Display_an_offline_map(QObject* parent /* = nullptr */):
  QObject(parent)
{

  Portal* portal = new Portal(false, this);
  m_portalItem = new PortalItem(portal, "YOUR_ITEM_ID", this); // Replace with your web map ID
  m_map = new Map(m_portalItem, this);
  m_offlineMapTask = new OfflineMapTask(m_map, this);

}

In the setMapView function, add a call to downloadPreplannedMapArea().

Display_an_offline_map.cpp
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Add line.void Display_an_offline_map::setMapView(MapQuickView* mapView)
{
  if (!mapView || mapView == m_mapView)
  {
    return;
  }

  m_mapView = mapView;

  m_mapView->setMap(m_map);

  downloadPreplannedMapArea();

  emit mapViewChanged();
}

In the downloadPreplannedMapArea(), retrieve a list of the preplanned map areas from the web map using the preplannedMapAreasAsync() method on the OfflineMapTask. Store the area you want to download to the member variable m_preplannedMapArea.

Display_an_offline_map.cpp
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Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.void Display_an_offline_map::downloadPreplannedMapArea()
{

  m_offlineMapTask->preplannedMapAreasAsync().then(this, [this]
    (QList<PreplannedMapArea*> preplannedMapAreas)
  {
    for (PreplannedMapArea* preplannedMapArea : preplannedMapAreas)
    {
      preplannedMapArea->load();
    }

    m_preplannedMapArea = preplannedMapAreas.at(0);

    });

}

To download an offline map to your device, you should provide a set of DownloadPreplannedOfflineMapParameters. To obtain a set of default parameters, pass in the m_preplannedMapArea to OfflineMapTask::createDefaultDownloadPreplannedOfflineMapParameters`.

Display_an_offline_map.cpp
Use dark colors for code blocks
Add line.Add line.Add line.Add line.Add line.Add line.void Display_an_offline_map::downloadPreplannedMapArea()
{

  m_offlineMapTask->preplannedMapAreasAsync().then(this, [this]
    (QList<PreplannedMapArea*> preplannedMapAreas)
  {
    for (PreplannedMapArea* preplannedMapArea : preplannedMapAreas)
    {
      preplannedMapArea->load();
    }

    m_preplannedMapArea = preplannedMapAreas.at(0);

    m_offlineMapTask->createDefaultDownloadPreplannedOfflineMapParametersAsync
      (m_preplannedMapArea).then(this, [this] (const
        DownloadPreplannedOfflineMapParameters& downloadPreplannedOfflineMapParameters)
    {

      });

    });

}

Create a directory to store the downloaded map area. You need to keep note of this directory path to retrieve the downloaded areas in the future.

Display_an_offline_map.cpp
Use dark colors for code blocks
Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.void Display_an_offline_map::downloadPreplannedMapArea()
{

  m_offlineMapTask->preplannedMapAreasAsync().then(this, [this]
    (QList<PreplannedMapArea*> preplannedMapAreas)
  {
    for (PreplannedMapArea* preplannedMapArea : preplannedMapAreas)
    {
      preplannedMapArea->load();
    }

    m_preplannedMapArea = preplannedMapAreas.at(0);

    m_offlineMapTask->createDefaultDownloadPreplannedOfflineMapParametersAsync
      (m_preplannedMapArea).then(this, [this] (const
        DownloadPreplannedOfflineMapParameters& downloadPreplannedOfflineMapParameters)
    {

      const QString packageDirPath = QStandardPaths::writableLocation(
        QStandardPaths::DownloadLocation)+"/offlinedata/";
      if (QDir(packageDirPath).exists())
      {
        QDir dir(packageDirPath);
        dir.removeRecursively();
      }

      QDir().mkdir(packageDirPath);

      const QString packagePath = packageDirPath +
        m_preplannedMapArea->portalItem()->title();

      });

    });

}

To download the offline map to your device, create a DownloadPreplannedOfflineMapJob and start() it. You may also print debugging information as the job occurs.

Display_an_offline_map.cpp
Use dark colors for code blocks
Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.void Display_an_offline_map::downloadPreplannedMapArea()
{

  m_offlineMapTask->preplannedMapAreasAsync().then(this, [this]
    (QList<PreplannedMapArea*> preplannedMapAreas)
  {
    for (PreplannedMapArea* preplannedMapArea : preplannedMapAreas)
    {
      preplannedMapArea->load();
    }

    m_preplannedMapArea = preplannedMapAreas.at(0);

    m_offlineMapTask->createDefaultDownloadPreplannedOfflineMapParametersAsync
      (m_preplannedMapArea).then(this, [this] (const
        DownloadPreplannedOfflineMapParameters& downloadPreplannedOfflineMapParameters)
    {

      const QString packageDirPath = QStandardPaths::writableLocation(
        QStandardPaths::DownloadLocation)+"/offlinedata/";
      if (QDir(packageDirPath).exists())
      {
        QDir dir(packageDirPath);
        dir.removeRecursively();
      }

      QDir().mkdir(packageDirPath);

      const QString packagePath = packageDirPath +
        m_preplannedMapArea->portalItem()->title();

      DownloadPreplannedOfflineMapJob* downloadPreplannedOfflineMapJob =
        m_offlineMapTask->downloadPreplannedOfflineMap(
        downloadPreplannedOfflineMapParameters, packagePath);

      connect(downloadPreplannedOfflineMapJob,
        &DownloadPreplannedOfflineMapJob::progressChanged, this,
        [downloadPreplannedOfflineMapJob]()
        {
          qDebug() << downloadPreplannedOfflineMapJob->progress();
        });

        downloadPreplannedOfflineMapJob->start();

      });

    });

}

If the job completes without errors, it will return an instance of DownloadPreplannedOfflineMapResult. If you want to display the map immediately, use DownloadPreplannedOfflineMapResult::offlineMap().

Display_an_offline_map.cpp
Use dark colors for code blocks
Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.void Display_an_offline_map::downloadPreplannedMapArea()
{

  m_offlineMapTask->preplannedMapAreasAsync().then(this, [this]
    (QList<PreplannedMapArea*> preplannedMapAreas)
  {
    for (PreplannedMapArea* preplannedMapArea : preplannedMapAreas)
    {
      preplannedMapArea->load();
    }

    m_preplannedMapArea = preplannedMapAreas.at(0);

    m_offlineMapTask->createDefaultDownloadPreplannedOfflineMapParametersAsync
      (m_preplannedMapArea).then(this, [this] (const
        DownloadPreplannedOfflineMapParameters& downloadPreplannedOfflineMapParameters)
    {

      const QString packageDirPath = QStandardPaths::writableLocation(
        QStandardPaths::DownloadLocation)+"/offlinedata/";
      if (QDir(packageDirPath).exists())
      {
        QDir dir(packageDirPath);
        dir.removeRecursively();
      }

      QDir().mkdir(packageDirPath);

      const QString packagePath = packageDirPath +
        m_preplannedMapArea->portalItem()->title();

      DownloadPreplannedOfflineMapJob* downloadPreplannedOfflineMapJob =
        m_offlineMapTask->downloadPreplannedOfflineMap(
        downloadPreplannedOfflineMapParameters, packagePath);

      connect(downloadPreplannedOfflineMapJob,
        &DownloadPreplannedOfflineMapJob::progressChanged, this,
        [downloadPreplannedOfflineMapJob]()
        {
          qDebug() << downloadPreplannedOfflineMapJob->progress();
        });

      connect(downloadPreplannedOfflineMapJob,
        &DownloadPreplannedOfflineMapJob::jobDone, this,
        [downloadPreplannedOfflineMapJob, this]()
        {
          DownloadPreplannedOfflineMapResult* downloadPreplannedOfflineMapResult =
            downloadPreplannedOfflineMapJob->result();

          if (!downloadPreplannedOfflineMapResult->hasErrors())
          {
            MobileMapPackage* mobileMapPackage =
              downloadPreplannedOfflineMapResult->mobileMapPackage();
            qDebug() << "Map " + mobileMapPackage->item()->title() +
              " was saved to " + mobileMapPackage->path();

            Map* map = downloadPreplannedOfflineMapResult->offlineMap();
            m_mapView->setMap(map);
          }
        });

        downloadPreplannedOfflineMapJob->start();

      });

    });

}

Press Ctrl + R to run the app.

Access the offline map

Inside MapViewModel.cs, create a private async function returning a Task called AccessMap().

MapViewModel.cs
Use dark colors for code blocksCopy
        private async Task AccessMap()
        {

        }

Inside the function, create a MobileMapPackage that references the path to the downloaded offline map area.

MapViewModel.cs
Use dark colors for code blocks
Add line.        private async Task AccessMap()
        {

            var mobileMapPackage = await MobileMapPackage.OpenAsync(_downloadLocation);

        }

Load the mobile map package and read the Map from it.

MapViewModel.cs
Use dark colors for code blocks
Add line.Add line.        private async Task AccessMap()
        {

            var mobileMapPackage = await MobileMapPackage.OpenAsync(_downloadLocation);

            await mobileMapPackage.LoadAsync();

            this.Map = mobileMapPackage.Maps.First();

        }

The function is now ready to be called to access a previously downloaded offline map area. You can trigger this function from a UI button click or by calling it directly from the constructor.
Click Debug > Start Debugging (or press F5 on the keyboard) to run the app.

Create a function called accessOfflineMap(). Inside it, check if the offline map package exists on the device file system.

MapViewModel
Use dark colors for code blocks
    suspend fun accessOfflineMap() {
        if (!File(localPathForOfflineMap).exists()) {
            return showMessage(context, "No offline map!")
        }

    }

Create a MobileMapPackage referencing the path to the offline map. Then load the mobile map package.

MapViewModel
Use dark colors for code blocks
    suspend fun accessOfflineMap() {
        if (!File(localPathForOfflineMap).exists()) {
            return showMessage(context, "No offline map!")
        }

        val mobileMapPackage = MobileMapPackage(localPathForOfflineMap)

        mobileMapPackage.load().onFailure { error ->
            return showMessage(context, "Mobile map package failed to load: ${error.message}")
        }

    }

Read the first map from the mobile map package.

MapViewModel
Expand
Use dark colors for code blocks
    suspend fun accessOfflineMap() {
        if (!File(localPathForOfflineMap).exists()) {
            return showMessage(context, "No offline map!")
        }

        val mobileMapPackage = MobileMapPackage(localPathForOfflineMap)

        mobileMapPackage.load().onFailure { error ->
            return showMessage(context, "Mobile map package failed to load: ${error.message}")
        }

        map = mobileMapPackage.maps.first()

    }
Expand

Create a function called makeMobileMapPackage which accepts a file path of the downloaded offline map as a parameter.

ContentView.swift
Use dark colors for code blocks
Add line.Add line.Add line.    func makeMobileMapPackage(offlineMapURL: URL) async throws {

    }

Create a MobileMapPackage referencing the downloaded offline map.

ContentView.swift
Use dark colors for code blocks
Add line.    func makeMobileMapPackage(offlineMapURL: URL) async throws {

        let mobileMapPackage = MobileMapPackage(fileURL: offlineMapURL)

    }

Load the mobile map package and read the map from it.

ContentView.swift
Expand
Use dark colors for code blocks
Add line.Add line.    func makeMobileMapPackage(offlineMapURL: URL) async throws {

        let mobileMapPackage = MobileMapPackage(fileURL: offlineMapURL)

        try await mobileMapPackage.load()
        let map = mobileMapPackage.maps.first

    }
Expand

The function is now ready to be called to access a previously downloaded offline map area. You can trigger this function from a button click or from the main function.

In Projects, double-click Headers > Display_an_offline_map.h to open the file. Add the accessOfflineMap() function declaration.

Display_an_offline_map.h
Use dark colors for code blocks
Add line.private:
    Esri::ArcGISRuntime::MapQuickView* mapView() const;
    void setMapView(Esri::ArcGISRuntime::MapQuickView* mapView);

    Esri::ArcGISRuntime::Map* m_map = nullptr;
    Esri::ArcGISRuntime::MapQuickView* m_mapView = nullptr;

    void downloadPreplannedMapArea();

    Esri::ArcGISRuntime::PortalItem* m_portalItem = nullptr;
    Esri::ArcGISRuntime::OfflineMapTask* m_offlineMapTask = nullptr;

    Esri::ArcGISRuntime::PreplannedMapArea* m_preplannedMapArea;

    void accessOfflineMap();

};

Create a MobileMapPackage that references the path where the downloaded web map area is located.

Display_an_offline_map.cpp
Use dark colors for code blocks
Add line.Add line.void Display_an_offline_map::accessOfflineMap()
{

    MobileMapPackage* mmpk = new MobileMapPackage("path//to//mmpk", this);

    return;

}

Call load() on the mobile map package and display the map area once the load finishes.

Display_an_offline_map.cpp
Use dark colors for code blocks
Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.void Display_an_offline_map::accessOfflineMap()
{

    MobileMapPackage* mmpk = new MobileMapPackage("path//to//mmpk", this);

    connect(mmpk, &MobileMapPackage::doneLoading, this, [this, mmpk](const Error& e)
    {
        if (e.isEmpty())
        {
            m_map = mmpk->maps().at(0);
            m_mapView->setMap(m_map);
        }
        else
        {
            qDebug() << e.message() << e.additionalMessage();
        }
    });
    mmpk->load();

    return;

}

The function is now ready to be called to access a previously downloaded offline map area. You can trigger this function from a UI button click or by calling it from another function.
Press Ctrl + R to run the app.