Create MapOverlaysPanel.cs

MapControl/Shared/MapOverlaysPanel.cs

@@ -0,0 +1,133 @@
+// XAML Map Control - https://github.com/ClemensFischer/XAML-Map-Control
+// Copyright © 2024 Clemens Fischer
+// Licensed under the Microsoft Public License (Ms-PL)
+
+using System;
+using System.Collections.Generic;
+using System.Collections.Specialized;
+using System.Diagnostics;
+using System.Linq;
+using Path = System.IO.Path;
+#if WPF
+using System.Windows;
+#elif UWP
+using Windows.UI.Xaml;
+#elif WINUI
+using Microsoft.UI.Xaml;
+#endif
+
+namespace MapControl
+{
+    /// <summary>
+    /// A MapPanel with a collection of GroundOverlay or GeoImage children.
+    /// </summary>
+    public partial class MapOverlaysPanel : MapPanel
+    {
+        public static readonly DependencyProperty SourcePathsProperty =
+            DependencyPropertyHelper.Register<MapOverlaysPanel, IEnumerable<string>>(nameof(SourcePaths), null,
+                (control, oldValue, newValue) => control.SourcePathsPropertyChanged(oldValue, newValue));
+
+        public IEnumerable<string> SourcePaths
+        {
+            get => (IEnumerable<string>)GetValue(SourcePathsProperty);
+            set => SetValue(SourcePathsProperty, value);
+        }
+
+        private void SourcePathsPropertyChanged(IEnumerable<string> oldSourcePaths, IEnumerable<string> newSourcePaths)
+        {
+            Children.Clear();
+
+            if (oldSourcePaths is INotifyCollectionChanged oldCollection)
+            {
+                oldCollection.CollectionChanged -= SourcePathsCollectionChanged;
+            }
+
+            if (newSourcePaths != null)
+            {
+                if (newSourcePaths is INotifyCollectionChanged newCollection)
+                {
+                    newCollection.CollectionChanged += SourcePathsCollectionChanged;
+                }
+
+                AddOverlays(0, newSourcePaths);
+            }
+        }
+
+        private void SourcePathsCollectionChanged(object sender, NotifyCollectionChangedEventArgs args)
+        {
+            switch (args.Action)
+            {
+                case NotifyCollectionChangedAction.Add:
+                    AddOverlays(args.NewStartingIndex, args.NewItems.Cast<string>());
+                    break;
+
+                case NotifyCollectionChangedAction.Remove:
+                    RemoveOverlays(args.OldStartingIndex, args.OldItems.Count);
+                    break;
+
+                case NotifyCollectionChangedAction.Move:
+                    RemoveOverlays(args.OldStartingIndex, args.OldItems.Count);
+                    AddOverlays(args.NewStartingIndex, args.NewItems.Cast<string>());
+                    break;
+
+                case NotifyCollectionChangedAction.Replace:
+                    ReplaceOverlays(args.NewStartingIndex, args.NewItems.Cast<string>());
+                    break;
+
+                case NotifyCollectionChangedAction.Reset:
+                    Children.Clear();
+                    AddOverlays(0, SourcePaths);
+                    break;
+            }
+        }
+
+        private void AddOverlays(int index, IEnumerable<string> sourcePaths)
+        {
+            foreach (var sourcePath in sourcePaths)
+            {
+                Children.Insert(index++, CreateOverlay(sourcePath));
+            }
+        }
+
+        private void ReplaceOverlays(int index, IEnumerable<string> sourcePaths)
+        {
+            foreach (var sourcePath in sourcePaths)
+            {
+                Children[index++] = CreateOverlay(sourcePath);
+            }
+        }
+
+        private void RemoveOverlays(int index, int count)
+        {
+            while (--count >= 0)
+            {
+                Children.RemoveAt(index);
+            }
+        }
+
+        protected virtual FrameworkElement CreateOverlay(string sourcePath)
+        {
+            var ext = Path.GetExtension(sourcePath).ToLower();
+            FrameworkElement overlay;
+
+            try
+            {
+                if (ext == ".kmz" || ext == ".kml")
+                {
+                    overlay = new GroundOverlay { SourcePath = sourcePath };
+                }
+                else
+                {
+                    overlay = new GeoImage { SourcePath = sourcePath };
+                }
+            }
+            catch (Exception ex)
+            {
+                Debug.WriteLine($"MapOverlaysControl: {sourcePath}: {ex.Message}");
+                overlay = new MapPanel();
+            }
+
+            return overlay;
+        }
+    }
+}