feat: Use CreateWindow instead of MainPage (#159)

src/BlazorBindings.Maui/BlazorBindingsApplication.cs

@@ -5,10 +5,19 @@ namespace BlazorBindings.Maui;
 public class BlazorBindingsApplication<[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] T>
     : Application where T : IComponent
 {
-    public BlazorBindingsApplication(IServiceProvider services)
+    public BlazorBindingsApplication()
     {
+#pragma warning disable CS0618 // Type or member is obsolete
         Configure();
+#pragma warning restore CS0618 // Type or member is obsolete
+    }
+
+    [Obsolete("Use parameterless constructor instead.")]
+    public BlazorBindingsApplication(IServiceProvider _) { }
 
+    protected override Window CreateWindow(Microsoft.Maui.IActivationState activationState)
+    {
+        var services = activationState?.Context?.Services ?? Handler.MauiContext.Services;
         var renderer = services.GetRequiredService<MauiBlazorBindingsRenderer>();
 
         if (WrapperComponentType != null)
@@ -18,18 +27,23 @@ public BlazorBindingsApplication(IServiceProvider services)
         }
 
         var (componentType, parameters) = GetComponentToRender();
-        var task = renderer.AddComponent(componentType, this, parameters);
+        var window = new Window();
+        var task = renderer.AddComponent(componentType, window, parameters);
         AwaitVoid(task);
 
+        return window;
+
         static async void AwaitVoid(Task task) => await task;
     }
 
     [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)]
     public virtual Type WrapperComponentType { get; }
 
+
     /// <summary>
     /// This method is executed before the rendering. It can be used to set resources, for example.
     /// </summary>
+    [Obsolete("Configure the application in the constructor instead.")]
     protected virtual void Configure() { }
 
     private (Type ComponentType, Dictionary<string, object> Parameters) GetComponentToRender()

src/BlazorBindings.Maui/Elements/Handlers/WindowHandler.cs

@@ -0,0 +1,25 @@
+using BlazorBindings.Maui.Extensions;
+using Microsoft.Maui.Controls;
+using MC = Microsoft.Maui.Controls;
+
+namespace BlazorBindings.Maui.Elements.Handlers;
+
+internal class WindowHandler(Window window) : IContainerElementHandler
+{
+    public void AddChild(object child, int physicalSiblingIndex)
+    {
+        window.Page = child.Cast<MC.Page>();
+    }
+
+    public void ReplaceChild(int physicalSiblingIndex, object oldChild, object newChild)
+    {
+        window.Page = newChild.Cast<MC.Page>();
+    }
+
+    public void RemoveChild(object child, int physicalSiblingIndex)
+    {
+        window.Page = null;
+    }
+
+    public object TargetElement => window;
+}

src/BlazorBindings.Maui/MauiBlazorBindingsRenderer.cs

@@ -22,12 +22,12 @@ internal MauiBlazorBindingsRenderer(MauiBlazorBindingsServiceProvider servicePro
 
     public override Dispatcher Dispatcher { get; } = new MauiDeviceDispatcher();
 
-    public Task AddComponent(
+    internal Task AddComponent(
         [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] Type componentType,
-        MC.Application parent, 
+        MC.Window parent,
         Dictionary<string, object> parameters = null)
     {
-        var handler = new ApplicationHandler(parent);
+        var handler = new WindowHandler(parent);
         var addComponentTask = AddComponent(componentType, handler, parameters);
 
         if (addComponentTask.Exception != null)
@@ -36,30 +36,17 @@ public Task AddComponent(
             ExceptionDispatchInfo.Throw(addComponentTask.Exception.InnerException);
         }
 
-        if (!addComponentTask.IsCompleted && parent is MC.Application app)
-        {
-            // MAUI requires the Application to have the MainPage. If rendering task is not completed synchronously,
-            // we need to set MainPage to something.
-            app.MainPage ??= new MC.ContentPage();
-        }
-
         return addComponentTask;
     }
 
-    public Task AddComponent<[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] T>(
-        MC.Application parent, Dictionary<string, object> parameters = null)
-    {
-        return AddComponent(typeof(T), parent, parameters);
-    }
-
     protected override void HandleException(Exception exception)
     {
         ExceptionDispatchInfo.Throw(exception);
     }
 
     // It tries to return the Element as soon as it is available, therefore Component task might still be in progress.
     internal async Task<(object Element, Task<IComponent> Component)> GetElementFromRenderedComponent(
-        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] Type componentType, 
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] Type componentType,
         Dictionary<string, object> parameters = null)
     {
         var (elements, addComponentTask) = await GetElementsFromRenderedComponent(componentType, parameters);

src/BlazorBindings.UnitTests/BlazorBindingsApplicationTests.cs

@@ -1,5 +1,7 @@
 using BlazorBindings.Maui;
 using BlazorBindings.UnitTests.Components;
+using Microsoft.Maui;
+using Microsoft.Maui.Controls;
 
 namespace BlazorBindings.UnitTests;
 
@@ -19,19 +21,23 @@ public void SetsTheMainPage_WithRootWrapper()
         PageContentWithCascadingParameter.ValidateContent(application.MainPage, WrapperWithCascadingValue.Value);
     }
 
-    private static BlazorBindingsApplication<T> CreateApplication<T>() where T : IComponent
+    private static Application CreateApplication<T>() where T : IComponent
     {
-        return new BlazorBindingsApplication<T>(TestServiceProvider.Create());
+        var application = TestApplication.Create<BlazorBindingsApplication<T>>();
+        ((IApplication)application).CreateWindow(new ActivationState(application.Handler.MauiContext));
+        return application;
     }
 
-    private static BlazorBindingsApplication<TMain> CreateApplicationWithWrapper<TMain, TWrapper>()
+    private static Application CreateApplicationWithWrapper<TMain, TWrapper>()
         where TMain : IComponent
         where TWrapper : IComponent
     {
-        return new BlazorBindingsApplicationWithWrapper<TMain, TWrapper>(TestServiceProvider.Create());
+        var application = TestApplication.Create<BlazorBindingsApplicationWithWrapper<TMain, TWrapper>>();
+        ((IApplication)application).CreateWindow(new ActivationState(application.Handler.MauiContext));
+        return application;
     }
 
-    class BlazorBindingsApplicationWithWrapper<TMain, TWrapper>(IServiceProvider services) : BlazorBindingsApplication<TMain>(services)
+    class BlazorBindingsApplicationWithWrapper<TMain, TWrapper> : BlazorBindingsApplication<TMain>
         where TMain : IComponent
         where TWrapper : IComponent
     {

src/BlazorBindings.UnitTests/Elements/ElementTestBase.razor

@@ -8,10 +8,13 @@
 @code {
     public ElementTestBase()
     {
-        MC.Application.Current = new TestApplication();
+        _application = TestApplication.Create();
+        _renderer = (TestBlazorBindingsRenderer)_application.Handler.MauiContext.Services.GetRequiredService<MauiBlazorBindingsRenderer>();
+        MC.Application.Current = _application;
     }
 
-    private TestBlazorBindingsRenderer _renderer = (TestBlazorBindingsRenderer)TestBlazorBindingsRenderer.Create();
+    private readonly MC.Application _application;
+    private readonly TestBlazorBindingsRenderer _renderer;
     private RenderFragmentComponent _renderedComponent;
 
     protected async Task<T> Render<T>(RenderFragment renderFragment)

src/BlazorBindings.UnitTests/MauiBlazorBindingsRendererTests.cs

@@ -1,30 +1,23 @@
-using BlazorBindings.UnitTests.Components;
+using BlazorBindings.Maui;
+using BlazorBindings.UnitTests.Components;
 
 namespace BlazorBindings.UnitTests;
 
 public class MauiBlazorBindingsRendererTests
 {
-    private readonly TestBlazorBindingsRenderer _renderer = (TestBlazorBindingsRenderer)TestBlazorBindingsRenderer.Create();
-    private readonly MC.Application _application = new TestApplication();
+    private readonly TestBlazorBindingsRenderer _renderer;
+    private readonly MC.Window _window = new();
 
     public MauiBlazorBindingsRendererTests()
     {
-        MC.Application.Current = _application;
-    }
-
-    [Test]
-    public async Task RenderToApplication_PageContent()
-    {
-        await _renderer.AddComponent<PageContent>(_application);
-
-        var content = _application.MainPage;
-        PageContent.ValidateContent(content);
+        var services = TestServiceProvider.CreateMauiAppBuilder().Build().Services;
+        _renderer = (TestBlazorBindingsRenderer)services.GetRequiredService<MauiBlazorBindingsRenderer>();
     }
 
     [Test]
     public void ShouldThrowExceptionIfHappenedDuringSyncRender()
     {
-        void action() => _ = _renderer.AddComponent<ComponentWithException>(_application);
+        void action() => _ = _renderer.AddComponent(typeof(ComponentWithException), _window);
 
         Assert.That(action, Throws.InvalidOperationException.With.Message.EqualTo("Should fail here."));
     }
@@ -34,8 +27,8 @@ public async Task RendererShouldHandleAsyncExceptions()
     {
         _renderer.ThrowExceptions = false;
 
-        await _renderer.AddComponent<PageWithButtonWithExceptionOnClick>(_application);
-        var button = (MC.Button)((MC.ContentPage)_application.MainPage).Content;
+        await _renderer.AddComponent(typeof(PageWithButtonWithExceptionOnClick), _window);
+        var button = (MC.Button)((MC.ContentPage)_window.Page).Content;
         button.SendClicked();
 
         Assert.That(() => _renderer.Exceptions, Is.Not.Empty.After(1000, 10));
@@ -45,18 +38,18 @@ public async Task RendererShouldHandleAsyncExceptions()
     [Test]
     public async Task RenderedComponentShouldBeAbleToReplaceMainPage()
     {
-        await _renderer.AddComponent(typeof(SwitchablePages), _application);
+        await _renderer.AddComponent(typeof(SwitchablePages), _window);
 
-        Assert.That(_application.MainPage.Title, Is.EqualTo("Page1"));
+        Assert.That(_window.Page.Title, Is.EqualTo("Page1"));
 
-        var switchButton = (MC.Button)((MC.ContentPage)_application.MainPage).Content;
+        var switchButton = (MC.Button)((MC.ContentPage)_window.Page).Content;
         switchButton.SendClicked();
 
-        Assert.That(_application.MainPage.Title, Is.EqualTo("Page2"));
+        Assert.That(_window.Page.Title, Is.EqualTo("Page2"));
 
-        switchButton = (MC.Button)((MC.ContentPage)_application.MainPage).Content;
+        switchButton = (MC.Button)((MC.ContentPage)_window.Page).Content;
         switchButton.SendClicked();
 
-        Assert.That(_application.MainPage.Title, Is.EqualTo("Page1"));
+        Assert.That(_window.Page.Title, Is.EqualTo("Page1"));
     }
 }

src/BlazorBindings.UnitTests/Navigation/NonUriNavigationTests.cs

@@ -2,7 +2,6 @@
 // Licensed under the MIT license.
 
 using BlazorBindings.UnitTests.Components;
-using Microsoft.Maui.Dispatching;
 
 namespace BlazorBindings.UnitTests.Navigation;
 
@@ -20,13 +19,11 @@ public NonUriNavigationTests(string root)
             ? (MC.Page)new MC.Shell { Items = { new MC.ContentPage { Title = "Root" } } }
             : new MC.NavigationPage(new MC.ContentPage { Title = "Root" });
 
-        var sp = TestServiceProvider.Create();
-        MC.Application.Current = new TestApplication(sp) { MainPage = mainPage };
+        var application = TestApplication.Create();
+        application.MainPage = mainPage;
+        MC.Application.Current = application;
 
-        var ctx = MC.Application.Current.Handler.MauiContext;
-        var dsp = ctx.Services.GetService<IDispatcher>();
-
-        _navigationService = sp.GetRequiredService<Maui.Navigation>();
+        _navigationService = application.Handler.MauiContext.Services.GetRequiredService<Maui.Navigation>();
         _mauiNavigation = mainPage.Navigation;
         _rootPage = _mauiNavigation.NavigationStack[0];
     }

src/BlazorBindings.UnitTests/Navigation/UriNavigationTests.cs

@@ -13,9 +13,10 @@ public class UriNavigationTests
     public UriNavigationTests()
     {
         var shell = new MC.Shell { Items = { new MC.ContentPage { Title = "Root" } } };
-        var sp = TestServiceProvider.Create();
-        MC.Application.Current = new TestApplication(sp) { MainPage = shell };
-        _navigationService = sp.GetRequiredService<Maui.Navigation>();
+        var application = TestApplication.Create();
+        application.MainPage = shell;
+        MC.Application.Current = application;
+        _navigationService = application.Handler.MauiContext.Services.GetRequiredService<Maui.Navigation>();
         _mauiNavigation = shell.Navigation;
     }
 

src/BlazorBindings.UnitTests/TestTypes.cs

@@ -2,6 +2,7 @@
 using Microsoft.Extensions.Logging;
 using Microsoft.Maui;
 using Microsoft.Maui.Controls;
+using Microsoft.Maui.Controls.Hosting;
 using Microsoft.Maui.Controls.Internals;
 using Microsoft.Maui.Hosting;
 using System.Runtime.ExceptionServices;
@@ -10,18 +11,30 @@
 
 namespace BlazorBindings.UnitTests;
 
-class TestApplication : MC.Application
+static class TestApplication
 {
-    public TestApplication(IServiceProvider serviceProvider = null)
+    class ApplicationFromTestAssembly : MC.Application;
+
+    public static MC.Application Create() => Create<ApplicationFromTestAssembly>();
+
+    public static T Create<T>() where T : MC.Application, new()
     {
-        serviceProvider ??= TestServiceProvider.Create();
-        Handler = new TestHandler
+        var mauiApp = TestServiceProvider
+            .CreateMauiAppBuilder()
+            .UseMauiApp<T>()
+            .Build();
+
+        var application = mauiApp.Services.GetRequiredService<IApplication>();
+
+        application.Handler = new TestHandler
         {
-            MauiContext = new MauiContext(serviceProvider),
-            VirtualView = this
+            MauiContext = new MauiContext(mauiApp.Services),
+            VirtualView = application
         };
 
         DependencyService.RegisterSingleton(new TestSystemResources());
+
+        return (T)application;
     }
 
     class TestHandler : IElementHandler
@@ -46,7 +59,7 @@ class TestSystemResources : ISystemResourcesProvider
 
 public static class TestServiceProvider
 {
-    public static IServiceProvider Create()
+    public static MauiAppBuilder CreateMauiAppBuilder()
     {
         var builder = MauiApp.CreateBuilder();
 
@@ -56,7 +69,7 @@ public static IServiceProvider Create()
         builder.UseMauiBlazorBindings();
         builder.Services.AddSingleton<MauiBlazorBindingsRenderer, TestBlazorBindingsRenderer>();
         builder.Services.AddSingleton<MauiDispatching.IDispatcher, TestDispatcher>();
-        return builder.Build().Services;
+        return builder;
     }
 
     class TestDispatcher : MauiDispatching.IDispatcher
@@ -96,11 +109,6 @@ protected override void HandleException(Exception exception)
 
     public override Dispatcher Dispatcher => NullDispatcher.Instance;
 
-    public static MauiBlazorBindingsRenderer Create()
-    {
-        return TestServiceProvider.Create().GetRequiredService<MauiBlazorBindingsRenderer>();
-    }
-
     sealed class NullDispatcher : Dispatcher
     {
         public static readonly Dispatcher Instance = new NullDispatcher();