Enable developers to inherit from BaseBehavior and BaseConverter again

src/CommunityToolkit.Maui.UnitTests/Behaviors/BaseBehaviorTests.cs

@@ -0,0 +1,47 @@
+using CommunityToolkit.Maui.UnitTests.Mocks;
+using FluentAssertions;
+using Xunit;
+
+namespace CommunityToolkit.Maui.UnitTests.Behaviors;
+
+public class BaseBehaviorTests
+{
+	[Fact]
+	public void AttachAndDetachCallsShouldCorrectlyAssignView()
+	{
+		var label = new Label();
+		var mockBehavior = new MockBehavior();
+
+		mockBehavior.AssertViewIsNull();
+		mockBehavior.IsAttached.Should().BeFalse();
+
+		label.Behaviors.Add(mockBehavior);
+
+		mockBehavior.AssertViewIsEqual(label);
+		mockBehavior.IsAttached.Should().BeTrue();
+
+		label.Behaviors.Remove(mockBehavior);
+
+		mockBehavior.AssertViewIsNull();
+		mockBehavior.IsAttached.Should().BeFalse();
+	}
+
+	[Fact]
+	public void ViewPropertyChangesShouldBeHandledWithinBehavior()
+	{
+		var label = new Label();
+		var mockBehavior = new MockBehavior();
+
+		label.Behaviors.Add(mockBehavior);
+
+		mockBehavior.PropertyChanges.Should().BeEmpty();
+
+		label.Text = "Text";
+
+		mockBehavior.PropertyChanges.Should().ContainSingle();
+		var change = mockBehavior.PropertyChanges.Single();
+
+		change.Should().NotBeNull();
+		change.PropertyName.Should().Be(nameof(Label.Text));
+	}
+}

src/CommunityToolkit.Maui.UnitTests/Mocks/MockBehavior.cs

@@ -0,0 +1,35 @@
+using System.ComponentModel;
+using CommunityToolkit.Maui.Behaviors;
+using FluentAssertions;
+
+namespace CommunityToolkit.Maui.UnitTests.Mocks;
+
+public class MockBehavior : BaseBehavior<Label>
+{
+	internal bool IsAttached { get; private set; }
+
+	protected override void OnAttachedTo(Label bindable)
+	{
+		base.OnAttachedTo(bindable);
+		IsAttached = true;
+	}
+
+	protected override void OnDetachingFrom(Label bindable)
+	{
+		base.OnDetachingFrom(bindable);
+		IsAttached = false;
+	}
+
+	internal void AssertViewIsEqual(Label label) => View.Should().Be(label);
+
+	internal void AssertViewIsNull() => View.Should().BeNull();
+
+	protected override void OnViewPropertyChanged(Label sender, PropertyChangedEventArgs e)
+	{
+		base.OnViewPropertyChanged(sender, e);
+
+		PropertyChanges.Add(e);
+	}
+
+	internal List<PropertyChangedEventArgs> PropertyChanges { get; } = [];
+}

src/CommunityToolkit.Maui/Behaviors/BaseBehavior.shared.cs

@@ -8,11 +8,6 @@ namespace CommunityToolkit.Maui.Behaviors;
 /// <typeparam name="TView">The <see cref="VisualElement"/> that the behavior can be applied to</typeparam>
 public abstract class BaseBehavior<TView> : Behavior<TView>, ICommunityToolkitBehavior<TView> where TView : VisualElement
 {
-	private protected BaseBehavior()
-	{
-
-	}
-
 	/// <summary>
 	/// View used by the Behavior
 	/// </summary>

src/CommunityToolkit.Maui/Converters/BaseConverter.shared.cs

@@ -13,11 +13,6 @@ namespace CommunityToolkit.Maui.Converters;
 /// <typeparam name="TParam">Type of parameter</typeparam>
 public abstract class BaseConverter<[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods)] TFrom, [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods)] TTo, TParam> : ValueConverterExtension, ICommunityToolkitValueConverter
 {
-	private protected BaseConverter()
-	{
-
-	}
-
 	/// <summary>
 	/// Default value to return when <see cref="IValueConverter.Convert(object?, Type, object?, CultureInfo?)"/> throws an <see cref="Exception"/>.
 	/// This value is used when <see cref="Maui.Options.ShouldSuppressExceptionsInConverters"/> is set to <see langword="true"/>.