Skip To Content ArcGIS for Developers Sign In Dashboard

ArcGIS Runtime SDK for .NET

Download preplanned map area

This code sample is available for these platforms:
View Sample on GitHub

Take a map offline using a preplanned map area.

Image of download preplanned map area

Use case

Generating offline maps on demand for a specific area can be time consuming for users and a processing load on the server. If areas of interest are known ahead of time, a web map author can pre-create packages for these areas. This way, the generation only needs to happen once, making the workflow more efficient for users and servers.

An archaeology team could define preplanned map areas for dig sites which can be taken offline for field use.

How to use the sample

Select a map area from the Preplanned Map Areas list. Click the button to download the selected area. The download progress will be shown in the Downloads list. When a download is complete, select it to display the offline map in the map view.

How it works

  1. Open the online Map from a PortalItem and display it.
  2. Create an OfflineMapTask using the portal item.
  3. Get the PreplannedMapAreas from the task, and then load them.
  4. To download a selected map area, create the default DownloadPreplannedOfflineMapParameters from the task using the selected preplanned map area.
  5. Set the update mode of the preplanned map area.
  6. Use the parameters and a download path to create a DownloadPreplannedOfflineMapJob from the task.
  7. Start the job. Once it has completed, get the DownloadPreplannedOfflineMapResult.
  8. Get the Map from the result and display it in the MapView.

Relevant API

  • DownloadPreplannedOfflineMapJob
  • DownloadPreplannedOfflineMapParameters
  • DownloadPreplannedOfflineMapResult
  • OfflineMapTask
  • PreplannedMapArea

About the data

The Naperville stormwater network map is based on ArcGIS Solutions for Stormwater and provides a realistic depiction of a theoretical stormwater network.

Additional information

PreplannedUpdateMode can be used to set the way the preplanned map area receives updates in several ways:

  • NoUpdates - No updates will be performed. This mode is intended for when a static snapshot of the data is required, and it does not create a replica on the service. This is the mode used for this sample.
  • SyncWithFeatureServices - Changes, including local edits, will be synced directly with the underlying feature services. This is the default update mode.
  • DownloadScheduledUpdates - Scheduled, read-only updates will be downloaded from the online map area and applied to the local mobile geodatabases.

See Take a map offline - preplanned to learn about preplanned workflows, including how to define preplanned areas in ArcGIS Online. Alternatively, visit Take a map offline - on demand or refer to the sample 'Generate Offline Map' to learn about the on-demand workflow and see how the workflows differ.

Tags

map area, offline, pre-planned, preplanned

Sample Code

<UserControl
    x:Class="ArcGISRuntime.UWP.Samples.DownloadPreplannedMap.DownloadPreplannedMap"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:esriUI="using:Esri.ArcGISRuntime.UI.Controls">
    <Grid>
        <esriUI:MapView x:Name="MyMapView" />
        <Border Style="{StaticResource BorderStyle}">
            <StackPanel>
                <Button
                    x:Name="ShowOnlineButton"
                    Margin="0,5,0,5"
                    HorizontalAlignment="Stretch"
                    Click="ShowOnlineButton_Click"
                    Content="Show Online Map"
                    IsEnabled="False" />
                <TextBlock
                    x:Name="MessageLabel"
                    Margin="5"
                    HorizontalAlignment="Center"
                    FontWeight="SemiBold"
                    Text="Select an area, then download it." />
                <ListView x:Name="AreasList" SelectionChanged="AreasList_SelectionChanged">
                    <ListView.ItemTemplate>
                        <DataTemplate>
                            <Grid>
                                <Grid.ColumnDefinitions>
                                    <ColumnDefinition Width="auto" />
                                    <ColumnDefinition Width="*" />
                                </Grid.ColumnDefinitions>
                                <Image
                                    Grid.RowSpan="2"
                                    Height="70"
                                    Margin="-10,2,2,2"
                                    Source="{Binding PortalItem.ThumbnailUri}"
                                    Stretch="UniformToFill" />
                                <TextBlock
                                    Grid.Column="1"
                                    Margin="10,0"
                                    VerticalAlignment="Center"
                                    Text="{Binding PortalItem.Title}" />
                            </Grid>
                        </DataTemplate>
                    </ListView.ItemTemplate>
                </ListView>
                <Button
                    x:Name="DownloadButton"
                    Margin="0,5,0,5"
                    HorizontalAlignment="Stretch"
                    Click="OnDownloadMapAreaClicked"
                    Content="Download preplanned area" />
                <Button
                    HorizontalAlignment="Stretch"
                    Click="OnDeleteAllMapAreasClicked"
                    Content="Delete offline areas" />
            </StackPanel>
        </Border>
        <!--  Busy indication  -->
        <Grid x:Name="BusyIndicator" Background="#807f7f7f">
            <Grid HorizontalAlignment="Center" VerticalAlignment="Center">
                <Grid.RowDefinitions>
                    <RowDefinition Height="auto" />
                    <RowDefinition Height="auto" />
                </Grid.RowDefinitions>
                <TextBlock
                    Margin="10"
                    FontSize="18"
                    Foreground="White">
                    <Run x:Name="BusyText" Text="Querying map areas..." />
                    <Run x:Name="BusyPercentage" Text="" />
                </TextBlock>
                <ProgressBar
                    x:Name="ProgressBar"
                    Grid.Row="1"
                    Width="100"
                    Height="10"
                    HorizontalAlignment="Center"
                    VerticalAlignment="Center"
                    IsEnabled="True"
                    IsIndeterminate="True" />
            </Grid>
        </Grid>
    </Grid>
</UserControl>
// Copyright 2019 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.

using ArcGISRuntime.Samples.Managers;
using Esri.ArcGISRuntime.Data;
using Esri.ArcGISRuntime.Mapping;
using Esri.ArcGISRuntime.Portal;
using Esri.ArcGISRuntime.Tasks.Offline;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using Windows.UI.Popups;
using Windows.UI.Xaml;

namespace ArcGISRuntime.UWP.Samples.DownloadPreplannedMap
{
    [ArcGISRuntime.Samples.Shared.Attributes.Sample(
        name: "Download preplanned map area",
        category: "Map",
        description: "Take a map offline using a preplanned map area.",
        instructions: "Select a map area from the Preplanned Map Areas list. Click the button to download the selected area. The download progress will be shown in the Downloads list. When a download is complete, select it to display the offline map in the map view.",
        tags: new[] { "map area", "offline", "pre-planned", "preplanned" })]
    public partial class DownloadPreplannedMap
    {
        // ID of a web map with preplanned map areas.
        private const string PortalItemId = "acc027394bc84c2fb04d1ed317aac674";

        // Folder to store the downloaded mobile map packages.
        private string _offlineDataFolder;

        // Task for taking map areas offline.
        private OfflineMapTask _offlineMapTask;

        // Hold onto the original map.
        private Map _originalMap;

        // Most recently opened map package.
        private MobileMapPackage _mobileMapPackage;

        public DownloadPreplannedMap()
        {
            InitializeComponent();
            Initialize();
        }

        private async void Initialize()
        {
            try
            {
                // Close the current mobile package when the sample closes.
                Unloaded += (s, e) => { _mobileMapPackage?.Close(); };

                // The data manager provides a method to get a suitable offline data folder.
                _offlineDataFolder = Path.Combine(DataManager.GetDataFolder(), "SampleData", "DownloadPreplannedMapAreas");

                // If temporary data folder doesn't exists, create it.
                if (!Directory.Exists(_offlineDataFolder))
                {
                    Directory.CreateDirectory(_offlineDataFolder);
                }

                // Create a portal to enable access to the portal item.
                ArcGISPortal portal = await ArcGISPortal.CreateAsync();

                // Create the portal item from the portal item ID.
                PortalItem webMapItem = await PortalItem.CreateAsync(portal, PortalItemId);

                // Show the map.
                _originalMap = new Map(webMapItem);
                MyMapView.Map = _originalMap;

                // Create an offline map task for the web map item.
                _offlineMapTask = await OfflineMapTask.CreateAsync(webMapItem);

                // Find the available preplanned map areas.
                IReadOnlyList<PreplannedMapArea> preplannedAreas = await _offlineMapTask.GetPreplannedMapAreasAsync();

                // Load each item, then add it to the UI.
                foreach (PreplannedMapArea area in preplannedAreas)
                {
                    await area.LoadAsync();
                    AreasList.Items.Add(area);
                }

                // Hide the loading indicator.
                BusyIndicator.Visibility = Visibility.Collapsed;
            }
            catch (Exception ex)
            {
                // Something unexpected happened, show the error message.
                Debug.WriteLine(ex);
                await new MessageDialog(ex.Message, "There was an error.").ShowAsync();
            }
        }

        private void ShowOnlineButton_Click(object sender, RoutedEventArgs e)
        {
            // Show the online map.
            MyMapView.Map = _originalMap;

            // Disable the button.
            ShowOnlineButton.IsEnabled = false;
        }

        private async Task DownloadMapAreaAsync(PreplannedMapArea mapArea)
        {
            // Close the current mobile package.
            _mobileMapPackage?.Close();

            // Set up UI for downloading.
            ProgressBar.IsIndeterminate = false;
            ProgressBar.Value = 0;
            BusyText.Text = "Downloading map area...";
            BusyIndicator.Visibility = Visibility.Visible;

            // Create folder path where the map package will be downloaded.
            string path = Path.Combine(_offlineDataFolder, mapArea.PortalItem.Title);

            // If the area is already downloaded, open it.
            if (Directory.Exists(path))
            {
                try
                {
                    // Open the offline map package.
                    _mobileMapPackage = await MobileMapPackage.OpenAsync(path);

                    // Display the first map.
                    MyMapView.Map = _mobileMapPackage.Maps.First();

                    // Update the UI.
                    BusyText.Text = string.Empty;
                    BusyIndicator.Visibility = Visibility.Collapsed;
                    MessageLabel.Text = "Opened offline area.";
                    return;
                }
                catch (Exception e)
                {
                    Debug.WriteLine(e);
                    await new MessageDialog(e.Message, "Couldn't open offline area. Proceeding to take area offline.").ShowAsync();
                }
            }

            // Create download parameters.
            DownloadPreplannedOfflineMapParameters parameters = await _offlineMapTask.CreateDefaultDownloadPreplannedOfflineMapParametersAsync(mapArea);

            // Set the update mode to not receive updates.
            parameters.UpdateMode = PreplannedUpdateMode.NoUpdates;

            // Create the job.
            DownloadPreplannedOfflineMapJob job = _offlineMapTask.DownloadPreplannedOfflineMap(parameters, path);

            // Set up event to update the progress bar while the job is in progress.
            job.ProgressChanged += OnJobProgressChanged;

            try
            {
                // Download the area.
                DownloadPreplannedOfflineMapResult results = await job.GetResultAsync();

                // Set the current mobile map package.
                _mobileMapPackage = results.MobileMapPackage;

                // Handle possible errors and show them to the user.
                if (results.HasErrors)
                {
                    // Accumulate all layer and table errors into a single message.
                    string errors = "";

                    foreach (KeyValuePair<Layer, Exception> layerError in results.LayerErrors)
                    {
                        errors = $"{errors}\n{layerError.Key.Name} {layerError.Value.Message}";
                    }

                    foreach (KeyValuePair<FeatureTable, Exception> tableError in results.TableErrors)
                    {
                        errors = $"{errors}\n{tableError.Key.TableName} {tableError.Value.Message}";
                    }

                    // Show the message.
                    await new MessageDialog(errors, "Warning!").ShowAsync();
                }

                // Show the downloaded map.
                MyMapView.Map = results.OfflineMap;

                // Update the UI.
                ShowOnlineButton.IsEnabled = true;
                DownloadButton.Content = "View downloaded area";
                MessageLabel.Text = "Downloaded preplanned area.";
            }
            catch (Exception ex)
            {
                // Report any errors.
                Debug.WriteLine(ex);
                await new MessageDialog(ex.Message, "Downloading map area failed.").ShowAsync();
            }
            finally
            {
                BusyText.Text = string.Empty;
                BusyIndicator.Visibility = Visibility.Collapsed;
            }
        }

        private async void OnJobProgressChanged(object sender, EventArgs e)
        {
            // Because the event is raised on a background thread, the dispatcher must be used to
            // ensure that UI updates happen on the UI thread.
            await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
            {
                // Update the UI with the progress.
                DownloadPreplannedOfflineMapJob downloadJob = sender as DownloadPreplannedOfflineMapJob;
                ProgressBar.Value = downloadJob.Progress;
                BusyPercentage.Text = $"{downloadJob.Progress}%";
            });
        }

        private async void OnDownloadMapAreaClicked(object sender, RoutedEventArgs e)
        {
            if (AreasList.SelectedItem != null)
            {
                PreplannedMapArea selectedMapArea = AreasList.SelectedItem as PreplannedMapArea;
                await DownloadMapAreaAsync(selectedMapArea);
            }
        }

        private async void OnDeleteAllMapAreasClicked(object sender, RoutedEventArgs e)
        {
            try
            {
                // Set up UI for downloading.
                ProgressBar.IsIndeterminate = true;
                BusyText.Text = "Deleting downloaded map area...";
                BusyIndicator.Visibility = Visibility.Visible;

                // Reset the map.
                MyMapView.Map = _originalMap;

                // Close the current mobile package.
                _mobileMapPackage?.Close();

                // Delete all data from the temporary data folder.
                Directory.Delete(_offlineDataFolder, true);
                Directory.CreateDirectory(_offlineDataFolder);

                // Update the UI.
                MessageLabel.Text = "Deleted downloaded areas.";
                DownloadButton.Content = "Download preplanned area";
                ShowOnlineButton.IsEnabled = false;
            }
            catch (Exception ex)
            {
                // Report the error.
                await new MessageDialog(ex.Message, "Deleting map areas failed.").ShowAsync();
            }
            finally
            {
                BusyIndicator.Visibility = Visibility.Collapsed;
            }
        }

        private void AreasList_SelectionChanged(object sender, Windows.UI.Xaml.Controls.SelectionChangedEventArgs e)
        {
            // Update the download button to reflect if the map area has already been downloaded.
            if (Directory.Exists(Path.Combine(_offlineDataFolder, (AreasList.SelectedItem as PreplannedMapArea).PortalItem.Title)))
            {
                DownloadButton.Content = "View downloaded area";
            }
            else
            {
                DownloadButton.Content = "Download preplanned area";
            }
        }
    }
}