Merge pull request #129 from CodebreakerApp/51-navigation

51 navigation

Author: christiannagel

src/CodeBreaker.Avalonia/CodeBreaker.Avalonia/App.axaml.cs

@@ -5,7 +5,9 @@
 using Codebreaker.ViewModels;
 using Codebreaker.ViewModels.Contracts.Services;
 using Codebreaker.ViewModels.Services;
+using CodeBreaker.Avalonia.Contracts.Services.Navigation;
 using CodeBreaker.Avalonia.Services;
+using CodeBreaker.Avalonia.Services.Navigation;
 using CodeBreaker.Avalonia.Views;
 using CodeBreaker.Avalonia.Views.Pages;
 using Microsoft.Extensions.Configuration;
@@ -28,11 +30,14 @@ public App()
         builder.Configuration.AddAppSettingsJson();
 
         // Services
+        builder.Services.AddNavigation<AvaloniaNavigationService>(pages => pages
+            .Configure<GamePage>("GamePage")
+            .Configure<TestPage>("TestPage")
+            .ConfigureInitialPage("GamePage"));
         builder.Services.Configure<GamePageViewModelOptions>(options => { });
         builder.Services.AddScoped<IInfoBarService, InfoBarService>();
         builder.Services.AddTransient<IDialogService, AvaloniaDialogService>();
         builder.Services.AddScoped<GamePageViewModel>();
-        builder.Services.AddTransient<GamePage>();
         builder.Services.AddHttpClient<IGamesClient, GamesClient>(client =>
         {
             client.BaseAddress = new(builder.Configuration.GetRequired("ApiBase"));
@@ -60,12 +65,12 @@ public override void OnFrameworkInitializationCompleted()
         {
             desktop.MainWindow = new MainWindow()
             {
-                Content = _host.Services.GetRequiredService<GamePage>()
+                Content = new Shell()
             };
         }
         else if (ApplicationLifetime is ISingleViewApplicationLifetime singleViewPlatform)
         {
-            singleViewPlatform.MainView = new GamePage();
+            singleViewPlatform.MainView = new Shell();
         }
 
         base.OnFrameworkInitializationCompleted();

src/CodeBreaker.Avalonia/CodeBreaker.Avalonia/Contracts/Services/Navigation/IAvaloniaNavigationService.cs

@@ -0,0 +1,11 @@
+using Avalonia.Controls;
+using Codebreaker.ViewModels.Contracts.Services;
+
+namespace CodeBreaker.Avalonia.Contracts.Services.Navigation;
+
+internal interface IAvaloniaNavigationService : INavigationService
+{
+    ContentControl CurrentPage { get; }
+
+    void Initialize();
+}

src/CodeBreaker.Avalonia/CodeBreaker.Avalonia/Contracts/Services/Navigation/IPageService.cs

@@ -0,0 +1,14 @@
+using Avalonia.Controls;
+
+namespace CodeBreaker.Avalonia.Contracts.Services.Navigation;
+
+internal interface IPageService
+{
+    string InitialPageKey { get; }
+
+    UserControl GetInitialPage();
+
+    UserControl GetPage(string key);
+
+    public UserControl this[string key] => GetPage(key);
+}

src/CodeBreaker.Avalonia/CodeBreaker.Avalonia/Services/Navigation/AvaloniaNavigationService.cs

@@ -0,0 +1,74 @@
+using Avalonia.Controls;
+using CodeBreaker.Avalonia.Contracts.Services.Navigation;
+using CommunityToolkit.Mvvm.ComponentModel;
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+namespace CodeBreaker.Avalonia.Services.Navigation;
+
+internal class AvaloniaNavigationService : ObservableObject, IAvaloniaNavigationService
+{
+    private readonly IPageService _pageService;
+
+    private readonly Stack<string> _navigationStack = new (100);
+
+    private ContentControl _currentPage = new UserControl();
+
+    public AvaloniaNavigationService(IPageService pageService)
+    {
+        _pageService = pageService;
+        _navigationStack.Push(pageService.InitialPageKey);
+    }
+
+    public ContentControl CurrentPage
+    {
+        get => _currentPage;
+        private set
+        {
+            if (value is null || value == _currentPage)
+                return;
+
+            OnPropertyChanging(nameof(CurrentPage));
+            _currentPage = value;
+            OnPropertyChanged(nameof(CurrentPage));
+        }
+    }
+
+    public bool CanGoBack => _navigationStack.Count != 0;
+
+    public void Initialize()
+    {
+        CurrentPage = _pageService.GetInitialPage();
+    }
+
+    public ValueTask<bool> GoBackAsync()
+    {
+        if (_navigationStack.TryPop(out _) && _navigationStack.TryPeek(out var key))
+            return NavigateToAsync(key);
+
+        return ValueTask.FromResult(false);
+    }
+
+    public ValueTask<bool> NavigateToAsync(string key, object? parameter = null, bool clearNavigation = false)
+    {
+        UserControl page;
+
+        try
+        {
+            page = _pageService[key];
+        }
+        catch (ArgumentException)
+        {
+            return ValueTask.FromResult(false);
+        }
+
+        CurrentPage = page;
+
+        if (clearNavigation)
+            _navigationStack.Clear();
+
+        _navigationStack.Push(key);
+        return ValueTask.FromResult(true);
+    }
+}

src/CodeBreaker.Avalonia/CodeBreaker.Avalonia/Services/Navigation/NavigationServiceDIExtensions.cs

@@ -0,0 +1,20 @@
+using Codebreaker.ViewModels.Contracts.Services;
+using CodeBreaker.Avalonia.Contracts.Services.Navigation;
+using Microsoft.Extensions.DependencyInjection;
+using System;
+
+namespace CodeBreaker.Avalonia.Services.Navigation;
+
+internal static class NavigationServiceDIExtensions
+{
+    public static IServiceCollection AddNavigation<TNavigationService>(this IServiceCollection services, Action<PageServiceBuilder> builder)
+        where TNavigationService : class, IAvaloniaNavigationService, INavigationService
+    {
+        PageServiceBuilder pageServiceBuilder = new();
+        builder(pageServiceBuilder);
+        services.AddSingleton<IPageService>(pageServiceBuilder.Build());
+        services.AddSingleton<IAvaloniaNavigationService, TNavigationService>();
+        services.AddSingleton<INavigationService>(x => x.GetRequiredService<IAvaloniaNavigationService>());
+        return services;
+    }
+}

src/CodeBreaker.Avalonia/CodeBreaker.Avalonia/Services/Navigation/PageService.cs

@@ -0,0 +1,26 @@
+using Avalonia.Controls;
+using CodeBreaker.Avalonia.Contracts.Services.Navigation;
+using System;
+using System.Collections.Generic;
+
+namespace CodeBreaker.Avalonia.Services.Navigation;
+
+internal class PageService(Dictionary<string, Func<UserControl>> pages, string initialPageKey) : IPageService
+{
+    public string InitialPageKey =>
+        initialPageKey;
+
+    public UserControl GetInitialPage() =>
+        GetPage(InitialPageKey);
+
+    public UserControl GetPage(string key)
+    {
+        Func<UserControl>? pageFactory;
+
+        lock (pages)
+            if (!pages.TryGetValue(key, out pageFactory))
+                throw new ArgumentException($"Page not found: {key}. Did you forget to call PageService.Configure?");
+
+        return pageFactory();
+    }
+}

src/CodeBreaker.Avalonia/CodeBreaker.Avalonia/Services/Navigation/PageServiceBuilder.cs

@@ -0,0 +1,50 @@
+using Avalonia.Controls;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace CodeBreaker.Avalonia.Services.Navigation;
+
+internal class PageServiceBuilder
+{
+    private readonly Dictionary<string, Func<UserControl>> _pages = new();
+
+    private string? _initialPage;
+
+    public PageServiceBuilder Configure<TView>()
+        where TView : UserControl, new() =>
+        Configure<TView>(typeof(TView).Name);
+
+    public PageServiceBuilder Configure<TView>(string key)
+        where TView : UserControl, new()
+    {
+        lock (_pages)
+        {
+            if (_pages.ContainsKey(key))
+                throw new ArgumentException($"The key {key} is already configured in {nameof(PageService)}");
+
+            var pageFactory = () => new TView();
+
+            if (_pages.ContainsValue(pageFactory))
+                throw new ArgumentException($"This type is already configured with key {_pages.First(p => p.Value == pageFactory).Key}");
+
+            _pages.Add(key, pageFactory);
+        }
+
+        return this;
+    }
+
+    public PageServiceBuilder ConfigureInitialPage(string key)
+    {
+        _initialPage = key;
+        return this;
+    }
+
+    public PageService Build()
+    {
+        if (_initialPage is null)
+            throw new ArgumentNullException(nameof(_initialPage), $"The initial page must be configured. Did you call .{nameof(ConfigureInitialPage)}?");
+
+        return new(_pages, _initialPage);
+    }
+}

src/CodeBreaker.Avalonia/CodeBreaker.Avalonia/Views/Pages/GamePage.axaml

@@ -14,10 +14,9 @@
     <UserControl.Resources>
         <converter:GameStatusToBooleanConverter x:Key="GameStatusToBooleanConverter" />
     </UserControl.Resources>
-    <Grid RowDefinitions="Auto,Auto,*">
-        <components:InfoBarArea Grid.Row="0" Margin="0,0,0,20"/>
-        <components:GameResultDisplay Grid.Row="1" />
-        <Grid Grid.Row="1"
+    <Grid RowDefinitions="Auto,*,Auto">
+        <components:GameResultDisplay Grid.Row="0" />
+        <Grid Grid.Row="0"
               RowDefinitions="Auto,*"
               ColumnDefinitions="3*,1*"
               Margin="8"
@@ -32,12 +31,12 @@
             </Button>
         </Grid>
         <components:PegSelectionView
-            Grid.Row="1"
+            Grid.Row="0"
             IsVisible="{Binding GameStatus, Mode=OneWay, Converter={StaticResource GameStatusToBooleanConverter}, ConverterParameter=Cancelable}"
             Margin="55,0,0,15" />
         <ItemsControl
             IsVisible="{Binding GameStatus, Mode=OneWay, ConverterParameter=Running}"
-            Grid.Row="2"
+            Grid.Row="1"
             ItemsSource="{Binding GameMoves, Mode=OneWay}"
             ItemTemplate="{StaticResource PegsTemplate}">
             <ItemsControl.ItemsPanel>
@@ -46,5 +45,6 @@
                 </ItemsPanelTemplate>
             </ItemsControl.ItemsPanel>
         </ItemsControl>
+        <Button Grid.Row="2" Content="To TestPage" Click="ToTestPageButtonClicked" />
     </Grid>
 </UserControl>

src/CodeBreaker.Avalonia/CodeBreaker.Avalonia/Views/Pages/GamePage.axaml.cs

@@ -1,15 +1,25 @@
 using Avalonia.Controls;
+using Avalonia.Interactivity;
 using Codebreaker.ViewModels;
+using Codebreaker.ViewModels.Contracts.Services;
 
 namespace CodeBreaker.Avalonia.Views.Pages;
 
 public partial class GamePage : UserControl
 {
+    private readonly INavigationService _navigationService;
+
     public GamePage()
     {
-        DataContext = App.Current.GetService<GamePageViewModel>(); ;
+        DataContext = App.Current.GetService<GamePageViewModel>();
         InitializeComponent();
+        _navigationService = App.Current.GetService<INavigationService>();
     }
 
     public GamePageViewModel ViewModel => (GamePageViewModel)DataContext!;
+
+    private void ToTestPageButtonClicked(object? sender, RoutedEventArgs e)
+    {
+        _navigationService.NavigateToAsync("TestPage");
+    }
 }

src/CodeBreaker.Avalonia/CodeBreaker.Avalonia/Views/Pages/Shell.axaml

@@ -0,0 +1,15 @@
+<UserControl xmlns="https://github.com/avaloniaui"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+             xmlns:pages="using:CodeBreaker.Avalonia.Views.Pages"
+             xmlns:components="using:CodeBreaker.Avalonia.Views.Components"
+             xmlns:navigationServices="using:CodeBreaker.Avalonia.Services.Navigation"
+             mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
+             x:Class="CodeBreaker.Avalonia.Shell"
+             x:DataType="navigationServices:AvaloniaNavigationService">
+    <Grid RowDefinitions="Auto, *">
+        <components:InfoBarArea Grid.Row="0" Margin="0,0,0,20"/>
+        <ContentPresenter Grid.Row="1" Content="{Binding CurrentPage, Mode=OneWay}" />
+    </Grid>
+</UserControl>