Add Reactive Page

global.json

@@ -1,7 +1,7 @@
 {
     "sdk": {
         "version": "8.0.10",
-        "rollForward": "latestMinor"
+        "rollForward": "latestFeature"
     },
     "msbuild-sdks": {
         "MSBuild.Sdk.Extras": "3.0.44"

src/CrissCross.WPF.UI/Controls/Page/ReactivePage.cs

@@ -0,0 +1,74 @@
+// Copyright (c) Chris Pulman. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using System.Windows;
+using System.Windows.Controls;
+using ReactiveUI;
+
+namespace CrissCross.WPF.UI.Controls;
+
+/// <summary>
+/// A <see cref="Page"/> that is reactive.
+/// </summary>
+/// <remarks>
+/// <para>
+/// This class is a <see cref="Page"/> that is also reactive. That is, it implements <see cref="IViewFor{TViewModel}"/>.
+/// You can extend this class to get an implementation of <see cref="IViewFor{TViewModel}"/> rather than writing one yourself.
+/// </para>
+/// <para>
+/// Note that the XAML for your control must specify the same base class, including the generic argument you provide for your view
+/// model. To do this, use the <c>TypeArguments</c> attribute as follows:
+/// <code>
+/// <![CDATA[
+/// <ui:ReactivePage
+///         x:Class="Foo.Bar.Views.YourView"
+///         x:TypeArguments="vms:YourViewModel"
+///         xmlns:ui="https://github.com/ChrisPulman/CrissCross.ui"
+///         xmlns:vms="clr-namespace:Foo.Bar.ViewModels"
+///         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+///         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+///         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+///         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+///         mc:Ignorable="d">
+///     <!-- view XAML here -->
+/// </ui:ReactivePage>
+/// ]]>
+/// </code>
+/// </para>
+/// </remarks>
+/// <typeparam name="TViewModel">
+/// The type of the view model backing the view.
+/// </typeparam>
+public class ReactivePage<TViewModel> :
+    Page, IViewFor<TViewModel>
+    where TViewModel : class
+{
+    /// <summary>
+    /// The view model dependency property.
+    /// </summary>
+    public static readonly DependencyProperty ViewModelProperty =
+        DependencyProperty.Register(
+                                    nameof(ViewModel),
+                                    typeof(TViewModel),
+                                    typeof(ReactivePage<TViewModel>),
+                                    new PropertyMetadata(null));
+
+    /// <summary>
+    /// Gets the binding root view model.
+    /// </summary>
+    public TViewModel? BindingRoot => ViewModel;
+
+    /// <inheritdoc/>
+    public TViewModel? ViewModel
+    {
+        get => (TViewModel)GetValue(ViewModelProperty);
+        set => SetValue(ViewModelProperty, value);
+    }
+
+    /// <inheritdoc/>
+    object? IViewFor.ViewModel
+    {
+        get => ViewModel;
+        set => ViewModel = (TViewModel?)value;
+    }
+}