Avalonia MapPath

MapControl/Avalonia/DependencyPropertyHelper.Avalonia.cs

@@ -56,10 +56,18 @@ namespace MapControl
         }
 
         public static StyledProperty<TValue> AddOwner<TOwner, TValue>(
-            StyledProperty<TValue> property)
+            StyledProperty<TValue> property,
+            Action<TOwner, TValue, TValue> changed = null)
             where TOwner : AvaloniaObject
         {
-            return property.AddOwner<TOwner>();
+            var newProperty = property.AddOwner<TOwner>();
+
+            if (changed != null)
+            {
+                newProperty.Changed.AddClassHandler<TOwner, TValue>((o, e) => changed(o, e.OldValue.Value, e.NewValue.Value));
+            }
+
+            return newProperty;
         }
 
         public static StyledProperty<TValue> AddOwner<TOwner, TValue>(

MapControl/Avalonia/MapBase.Avalonia.cs

@@ -112,7 +112,7 @@ namespace MapControl
         /// </summary>
         public double ViewScale
         {
-            get => (double)GetValue(ViewScaleProperty);
+            get => GetValue(ViewScaleProperty);
             private set => RaisePropertyChanged(ViewScaleProperty, double.NaN, value);
         }
 

MapControl/Avalonia/MapControl.Avalonia.csproj

@@ -28,7 +28,6 @@
         <Compile Remove="..\Shared\MapGraticule.cs" />
         <Compile Remove="..\Shared\MapItem.cs" />
         <Compile Remove="..\Shared\MapItemsControl.cs" />
-        <Compile Remove="..\Shared\MapPath.cs" />
         <Compile Remove="..\Shared\MapPolyline.cs" />
         <Compile Remove="..\Shared\MapPolygon.cs" />
         <Compile Remove="..\Shared\ViewTransform.cs" />

MapControl/Avalonia/MapPath.Avalonia.cs

@@ -0,0 +1,101 @@
+// XAML Map Control - https://github.com/ClemensFischer/XAML-Map-Control
+// Copyright © 2024 Clemens Fischer
+// Licensed under the Microsoft Public License (Ms-PL)
+
+using Avalonia.Controls.Shapes;
+using Avalonia.Media;
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Collections.Specialized;
+using System.Linq;
+
+namespace MapControl
+{
+    public partial class MapPath : Shape
+    {
+        public MapPath()
+        {
+            Stretch = Stretch.None;
+        }
+
+        public static readonly StyledProperty<Geometry> DataProperty =
+            DependencyPropertyHelper.AddOwner<MapPath, Geometry>(Path.DataProperty,
+                (path, oldValue, newValue) => path.DataPropertyChanged(oldValue, newValue));
+
+        public Geometry Data
+        {
+            get => GetValue(DataProperty);
+            set => SetValue(DataProperty, value);
+        }
+
+        protected override Geometry CreateDefiningGeometry() => Data;
+
+        private void DataPropertyChanged(Geometry oldData, Geometry newData)
+        {
+            // Check if data is actually a new Geometry.
+            //
+            if (newData != null && !ReferenceEquals(newData, oldData))
+            {
+                UpdateData();
+            }
+        }
+
+        private void SetMapTransform(Matrix matrix)
+        {
+            if (Data.Transform is MatrixTransform transform)
+            {
+                transform.Matrix = matrix;
+            }
+            else
+            {
+                Data.Transform = new MatrixTransform(matrix);
+            }
+        }
+
+        #region Methods used only by derived classes MapPolyline, MapPolygon and MapMultiPolygon
+
+        protected void DataCollectionPropertyChanged(IEnumerable oldValue, IEnumerable newValue)
+        {
+            if (oldValue is INotifyCollectionChanged oldCollection)
+            {
+                oldCollection.CollectionChanged -= DataCollectionChanged;
+            }
+
+            if (newValue is INotifyCollectionChanged newCollection)
+            {
+                newCollection.CollectionChanged += DataCollectionChanged;
+            }
+
+            UpdateData();
+        }
+
+        protected void DataCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
+        {
+            UpdateData();
+        }
+
+        protected void AddPolylinePoints(PathFigures pathFigures, IEnumerable<Location> locations, double longitudeOffset, bool closed)
+        {
+            if (locations.Count() >= 2)
+            {
+                var points = locations
+                    .Select(location => LocationToView(location, longitudeOffset))
+                    .Where(point => point.HasValue)
+                    .Select(point => point.Value);
+
+                var figure = new PathFigure
+                {
+                    StartPoint = points.First(),
+                    IsClosed = closed,
+                    IsFilled = true
+                };
+
+                figure.Segments.Add(new PolyLineSegment(points.Skip(1)));
+                pathFigures.Add(figure);
+            }
+        }
+
+        #endregion
+    }
+}