Create and save map

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
// Copyright 2021 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 ArcGIS.Helpers;
using Esri.ArcGISRuntime.Geometry;
using Esri.ArcGISRuntime.Mapping;
using Esri.ArcGISRuntime.Portal;
using Esri.ArcGISRuntime.UI;
using Microsoft.UI.Xaml;
using Microsoft.UI.Xaml.Controls;
using System;
using System.Collections.Generic;
using System.IO;
using System.Threading.Tasks;

namespace ArcGIS.WinUI.Samples.AuthorMap
{
    [ArcGIS.Samples.Shared.Attributes.Sample(
        name: "Create and save map",
        category: "Map",
        description: "Create and save a map as an ArcGIS `PortalItem` (i.e. web map).",
        instructions: "1. Select the basemap and layers you'd like to add to your map.",
        tags: new[] { "ArcGIS Online", "OAuth", "portal", "publish", "share", "web map" })]
    [ArcGIS.Samples.Shared.Attributes.ClassFile("Helpers\\ArcGISLoginPrompt.cs")]
    public partial class AuthorMap
    {
        // String array to store names of the available basemaps
        private readonly string[] _basemapNames = {
            "Light Gray",
            "Topographic",
            "Streets",
            "Imagery",
            "Ocean"
        };

        // Dictionary of operational layer names and URLs
        private readonly Dictionary<string, string> _operationalLayerUrls = new Dictionary<string, string>
        {
            {"World Elevations", "https://sampleserver6.arcgisonline.com/arcgis/rest/services/Elevation/WorldElevations/MapServer"},
            {"World Cities", "https://sampleserver6.arcgisonline.com/arcgis/rest/services/SampleWorldCities/MapServer/" },
            {"US Census Data", "https://sampleserver6.arcgisonline.com/arcgis/rest/services/Census/MapServer"}
        };

        public AuthorMap()
        {
            InitializeComponent();

            // Create the UI, setup the control references and execute initialization
            _ = Initialize();
        }

        private async Task Initialize()
        {
            ArcGISLoginPrompt.SetChallengeHandler(this);

            bool loggedIn = await ArcGISLoginPrompt.EnsureAGOLCredentialAsync();

            // Show a plain gray map in the map view
            if (loggedIn)
            {
                MyMapView.Map = new Map(BasemapStyle.ArcGISLightGray);
            }
            else MyMapView.Map = new Map();

            // Update the UI with basemaps and layers
            BasemapListBox.ItemsSource = _basemapNames;

            OperationalLayerListBox.ItemsSource = _operationalLayerUrls;

            // Add a listener for changes in the selected basemap.
            BasemapListBox.SelectionChanged += BasemapSelectionChanged;

            // Update the extent labels whenever the view point (extent) changes
            MyMapView.ViewpointChanged += (s, evt) => UpdateViewExtentLabels();
        }

        #region UI event handlers

        private void LayerSelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            // Call a function to add operational layers to the map
            AddOperationalLayers();
        }

        private async void SaveMapClicked(object sender, RoutedEventArgs e)
        {
            try
            {
                // Show the progress bar so the user knows work is happening
                SaveProgressBar.Visibility = Visibility.Visible;

                // Get the current map
                Map myMap = MyMapView.Map;

                // Apply the current extent as the map's initial extent
                myMap.InitialViewpoint = MyMapView.GetCurrentViewpoint(ViewpointType.BoundingGeometry);

                // Export the current map view to use as the item's thumbnail
                RuntimeImage thumbnailImg = await MyMapView.ExportImageAsync();

                // See if the map has already been saved (has an associated portal item)
                if (myMap.Item == null)
                {
                    // Get information for the new portal item
                    string title = TitleTextBox.Text;
                    string description = DescriptionTextBox.Text;
                    string tagText = TagsTextBox.Text;

                    // Make sure all required info was entered
                    if (string.IsNullOrEmpty(title) || string.IsNullOrEmpty(description) || string.IsNullOrEmpty(tagText))
                    {
                        throw new Exception("Please enter a title, description, and some tags to describe the map.");
                    }

                    // Call a function to save the map as a new portal item
                    await SaveNewMapAsync(MyMapView.Map, title, description, tagText.Split(','), thumbnailImg);

                    // Report a successful save
                    await new MessageDialog2("Saved '" + title + "' to ArcGIS Online!", "Map Saved").ShowAsync();
                }
                else
                {
                    // This is not the initial save, call SaveAsync to save changes to the existing portal item
                    await myMap.SaveAsync();

                    // Get the file stream from the new thumbnail image
                    Stream imageStream = await thumbnailImg.GetEncodedBufferAsync();

                    // Update the item thumbnail
                    ((PortalItem)myMap.Item).SetThumbnail(imageStream);
                    await myMap.SaveAsync();

                    // Report update was successful
                    await new MessageDialog2("Saved changes to '" + myMap.Item.Title + "'", "Updates Saved").ShowAsync();
                }
            }
            catch (Exception ex)
            {
                // Report error message
                await new MessageDialog2("Error saving map to ArcGIS Online: " + ex.Message).ShowAsync();
            }
            finally
            {
                // Hide the progress bar
                SaveProgressBar.Visibility = Visibility.Collapsed;
            }
        }

        private void NewMapClicked(object sender, RoutedEventArgs e)
        {
            // Create a new map (will not have an associated PortalItem)
            MyMapView.Map = new Map(BasemapStyle.ArcGISLightGray);
            MyMapView.Map.Basemap.LoadAsync();

            // Reset the basemap selection in the UI
            BasemapListBox.SelectedIndex = 0;

            // Reset the layer selection in the UI;
            OperationalLayerListBox.SelectedIndex = -1;

            // Reset the extent labels
            UpdateViewExtentLabels();
        }

        #endregion UI event handlers

        private void ApplyBasemap(string basemapName)
        {
            // Set the basemap for the map according to the user's choice in the list box.
            switch (basemapName)
            {
                case "Light Gray":
                    MyMapView.Map.Basemap = new Basemap(BasemapStyle.ArcGISLightGray);
                    break;

                case "Topographic":
                    MyMapView.Map.Basemap = new Basemap(BasemapStyle.ArcGISTopographic);
                    break;

                case "Streets":
                    MyMapView.Map.Basemap = new Basemap(BasemapStyle.ArcGISStreets);
                    break;

                case "Imagery":
                    MyMapView.Map.Basemap = new Basemap(BasemapStyle.ArcGISImagery);
                    break;

                case "Ocean":
                    MyMapView.Map.Basemap = new Basemap(BasemapStyle.ArcGISOceans);
                    break;
            }

            MyMapView.Map.Basemap.LoadAsync();
        }

        private void AddOperationalLayers()
        {
            // Clear the operational layers from the map
            Map myMap = MyMapView.Map;
            myMap.OperationalLayers.Clear();

            // Loop through the selected items in the operational layers list box
            foreach (KeyValuePair<string, string> item in OperationalLayerListBox.SelectedItems)
            {
                // Get the service uri for each selected item
                KeyValuePair<string, string> layerInfo = item;
                Uri layerUri = new Uri(layerInfo.Value);

                // Create a new map image layer, set it 50% opaque, and add it to the map
                ArcGISMapImageLayer layer = new ArcGISMapImageLayer(layerUri)
                {
                    Opacity = 0.5
                };
                myMap.OperationalLayers.Add(layer);
            }
        }

        private async Task SaveNewMapAsync(Map myMap, string title, string description, string[] tags, RuntimeImage img)
        {
            await ArcGISLoginPrompt.EnsureAGOLCredentialAsync();

            // Get the ArcGIS Online portal (will use credential from login above)
            ArcGISPortal agsOnline = await ArcGISPortal.CreateAsync();

            // Save the current state of the map as a portal item in the user's default folder
            await myMap.SaveAsAsync(agsOnline, null, title, description, tags, img);
        }

        private void UpdateViewExtentLabels()
        {
            // Get the current view point for the map view
            Viewpoint currentViewpoint = MyMapView.GetCurrentViewpoint(ViewpointType.BoundingGeometry);
            if (currentViewpoint == null) { return; }

            // Get the current map extent (envelope) from the view point
            Envelope currentExtent = currentViewpoint.TargetGeometry as Envelope;

            // Project the current extent to geographic coordinates (longitude / latitude)
            Envelope currentGeoExtent = (Envelope)currentExtent.Project(SpatialReferences.Wgs84);

            // Fill the app text boxes with min / max longitude (x) and latitude (y) to four decimal places
            XMinTextBox.Text = currentGeoExtent.XMin.ToString("0.####");
            YMinTextBox.Text = currentGeoExtent.YMin.ToString("0.####");
            XMaxTextBox.Text = currentGeoExtent.XMax.ToString("0.####");
            YMaxTextBox.Text = currentGeoExtent.YMax.ToString("0.####");
        }

        private void BasemapSelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            // Get the name of the desired basemap
            string name = e.AddedItems[0].ToString();

            // Apply the basemap to the current map
            ApplyBasemap(name);
        }
    }
}