DrawingView.Points is now unique per instance (#1478)

Author: bijington

src/CommunityToolkit/Xamarin.CommunityToolkit.UnitTests/Views/DrawingView_Tests.cs

@@ -0,0 +1,23 @@
+using NUnit.Framework;
+using Xamarin.CommunityToolkit.UI.Views;
+using Xamarin.Forms;
+
+namespace Xamarin.CommunityToolkit.UnitTests.Views
+{
+	public class DrawingView_Tests
+	{
+		[Test]
+		public void AllInstancesShouldHaveTheirOwnPoints()
+		{
+			var drawingViewOne = new DrawingView();
+			var drawingViewTwo = new DrawingView();
+
+			drawingViewOne.Points.Add(Point.Zero);
+
+			drawingViewTwo.Points.Clear();
+
+			Assert.IsNotEmpty(drawingViewOne.Points);
+			Assert.IsFalse(ReferenceEquals(drawingViewOne.Points, drawingViewTwo.Points));
+		}
+	}
+}

src/CommunityToolkit/Xamarin.CommunityToolkit/Views/DrawingView/DrawingView.shared.cs

@@ -27,7 +27,7 @@ public class DrawingView : View
 			BindableProperty.Create(nameof(ClearOnFinish), typeof(bool), typeof(DrawingView), default(bool));
 
 		public static readonly BindableProperty PointsProperty = BindableProperty.Create(
-			nameof(Points), typeof(ObservableCollection<Point>), typeof(DrawingView), new ObservableCollection<Point>(), BindingMode.TwoWay);
+			nameof(Points), typeof(ObservableCollection<Point>), typeof(DrawingView), default, BindingMode.TwoWay);
 
 		public static readonly BindableProperty DrawingCompletedCommandProperty = BindableProperty.Create(
 			nameof(DrawingCompletedCommand), typeof(ICommand), typeof(DrawingView));
@@ -74,6 +74,11 @@ public bool ClearOnFinish
 			set => SetValue(ClearOnFinishProperty, value);
 		}
 
+		public DrawingView()
+		{
+			Points = new ObservableCollection<Point>();
+		}
+
 		static object CoerceValue(BindableObject bindable, object value)
 			=> ((DrawingView)bindable).CoerceValue((int)value);