feat(desktop): Add back navigation between views

docs/changelog.html

@@ -27,7 +27,7 @@
 
 		<label>Changelog:</label>
 		<ul>
-			<li style="display: none"><a href="#unreleased">Unreleased</a></li>
+			<li><a href="#unreleased">Unreleased</a></li>
 			<li><a href="#v0.8.2">v0.8.2</a></li>
 			<li><a href="#v0.8.1">v0.8.1</a></li>
 			<li><a href="#v0.8.0">v0.8.0</a></li>
@@ -49,15 +49,20 @@
 
 <main id="top" class="content">
 	<h1>Changelog</h1>
-	<section id="unreleased" hidden="hidden">
+	<section id="unreleased">
 		<div>
 			<a style="display: inline" href="#unreleased"><img src="link.png" alt="link"/></a>
 			<h2 style="display: inline">Unreleased</h2>
 		</div>
 
-		<section id="unreleased_added" hidden="hidden">
+		<section id="unreleased_added">
 			<h3>Added</h3>
-			<ul></ul>
+			<ul>
+				<li>
+					Ability to navigate back to previous pages in
+					<a href="https://github.com/VMelnalksnis/Gnomeshade/pull/1236">#1236</a>
+				</li>
+			</ul>
 		</section>
 
 		<section id="unreleased_changed" hidden="hidden">

docs/sitemap.xml

@@ -14,6 +14,6 @@
 	</url>
 	<url>
 		<loc>https://www.gnomeshade.org/changelog</loc>
-		<lastmod>2024-05-15</lastmod>
+		<lastmod>2024-05-20</lastmod>
 	</url>
 </urlset>

source/Gnomeshade.Avalonia.Core/Interactivity/HotKeyBehaviour.cs

@@ -0,0 +1,67 @@
+// Copyright 2021 Valters Melnalksnis
+// Licensed under the GNU Affero General Public License v3.0 or later.
+// See LICENSE.txt file in the project root for full license information.
+
+using System.Windows.Input;
+
+using Avalonia;
+using Avalonia.Controls;
+using Avalonia.Input;
+using Avalonia.Xaml.Interactivity;
+
+namespace Gnomeshade.Avalonia.Core.Interactivity;
+
+/// <summary>Behaviour that executes a command when a hotkey has been pressed.</summary>
+public sealed class HotKeyBehaviour : Trigger<Control>
+{
+	/// <summary>Identifies the <seealso cref="TopLevel"/> avalonia property.</summary>
+	public static readonly DirectProperty<HotKeyBehaviour, TopLevel?> TopLevelProperty =
+		AvaloniaProperty.RegisterDirect<HotKeyBehaviour, TopLevel?>(
+			nameof(TopLevel),
+			behaviour => behaviour.TopLevel,
+			(behaviour, topLevel) => behaviour.TopLevel = topLevel);
+
+	/// <summary>Identifies the <seealso cref="HotKey"/> avalonia property.</summary>
+	public static readonly DirectProperty<HotKeyBehaviour, KeyGesture?> HotKeyProperty =
+		AvaloniaProperty.RegisterDirect<HotKeyBehaviour, KeyGesture?>(
+			nameof(HotKey),
+			behaviour => behaviour.HotKey,
+			(behaviour, keyGesture) => behaviour.HotKey = keyGesture);
+
+	/// <summary>Identifies the <seealso cref="Command"/> avalonia property.</summary>
+	public static readonly DirectProperty<HotKeyBehaviour, ICommand?> CommandProperty =
+		AvaloniaProperty.RegisterDirect<HotKeyBehaviour, ICommand?>(
+			nameof(Command),
+			behaviour => behaviour.Command,
+			(behaviour, command) => behaviour.Command = command);
+
+	private KeyBinding? _gesture;
+
+	/// <summary>Gets or sets the <see cref="TopLevel"/> control in which to register the <see cref="HotKey"/>.</summary>
+	public TopLevel? TopLevel { get; set; }
+
+	/// <summary>Gets or sets the <see cref="KeyGesture"/> which will trigger the <see cref="Command"/>.</summary>
+	public KeyGesture? HotKey { get; set; }
+
+	/// <summary>Gets or sets the <see cref="ICommand"/> that will be executed when <see cref="HotKey"/> is pressed.</summary>
+	public ICommand? Command { get; set; }
+
+	/// <inheritdoc />
+	protected override void OnAttachedToVisualTree()
+	{
+		if (TopLevel is { } topLevel && Command is { } command && HotKey is { } hotKey)
+		{
+			_gesture = new() { Command = command, Gesture = hotKey };
+			topLevel.KeyBindings.Add(_gesture);
+		}
+	}
+
+	/// <inheritdoc />
+	protected override void OnDetachedFromVisualTree()
+	{
+		if (TopLevel is { } topLevel && _gesture is { } gesture)
+		{
+			topLevel.KeyBindings.Remove(gesture);
+		}
+	}
+}

source/Gnomeshade.Avalonia.Core/Interactivity/PointerReleasedTrigger.cs

@@ -0,0 +1,73 @@
+// Copyright 2021 Valters Melnalksnis
+// Licensed under the GNU Affero General Public License v3.0 or later.
+// See LICENSE.txt file in the project root for full license information.
+
+using Avalonia;
+using Avalonia.Input;
+using Avalonia.Interactivity;
+using Avalonia.Xaml.Interactivity;
+
+namespace Gnomeshade.Avalonia.Core.Interactivity;
+
+/// <summary>Triggers actions based on <see cref="InputElement.PointerReleasedEvent"/> routed event.</summary>
+public sealed class PointerReleasedTrigger : Trigger<InputElement>
+{
+	/// <summary>Identifies the <seealso cref="SourceInteractive"/> avalonia property.</summary>
+	public static readonly StyledProperty<Interactive?> SourceInteractiveProperty =
+		AvaloniaProperty.Register<PointerReleasedTrigger, Interactive?>(nameof(SourceInteractive));
+
+	/// <summary>Identifies the <seealso cref="MouseButton"/> avalonia property.</summary>
+	public static readonly StyledProperty<MouseButton> MouseButtonProperty =
+		AvaloniaProperty.Register<PointerReleasedTrigger, MouseButton>(nameof(MouseButton));
+
+	private bool _isInitialized;
+
+	/// <summary>
+	/// Gets or sets the source object from which this behavior listens for events.
+	/// If <seealso cref="SourceInteractive"/> is not set, the source will default to <seealso cref="Behavior.AssociatedObject"/>. This is an avalonia property.
+	/// </summary>
+	public Interactive? SourceInteractive
+	{
+		get => GetValue(SourceInteractiveProperty);
+		set => SetValue(SourceInteractiveProperty, value);
+	}
+
+	/// <summary>Gets or sets the mouse button for which the trigger will list for.</summary>
+	public MouseButton MouseButton
+	{
+		get => GetValue(MouseButtonProperty);
+		set => SetValue(MouseButtonProperty, value);
+	}
+
+	private static RoutedEvent<PointerReleasedEventArgs> RoutedEvent => InputElement.PointerReleasedEvent;
+
+	private Interactive? Interactive => SourceInteractive ?? AssociatedObject;
+
+	/// <inheritdoc />
+	protected override void OnAttachedToVisualTree()
+	{
+		if (Interactive is { } interactive)
+		{
+			interactive.AddHandler(RoutedEvent, Handler, RoutingStrategies.Tunnel);
+			_isInitialized = true;
+		}
+	}
+
+	/// <inheritdoc />
+	protected override void OnDetachedFromVisualTree()
+	{
+		if (Interactive is { } interactive && _isInitialized)
+		{
+			interactive.RemoveHandler(RoutedEvent, Handler);
+			_isInitialized = false;
+		}
+	}
+
+	private void Handler(object? sender, PointerReleasedEventArgs e)
+	{
+		if (Interactive is { } interactive && e.InitialPressMouseButton == MouseButton)
+		{
+			Interaction.ExecuteActions(interactive, Actions, e);
+		}
+	}
+}

source/Gnomeshade.Avalonia.Core/MainWindowViewModel.cs

@@ -3,6 +3,7 @@
 // See LICENSE.txt file in the project root for full license information.
 
 using System;
+using System.Collections.Generic;
 using System.ComponentModel;
 using System.Threading.Tasks;
 
@@ -37,6 +38,7 @@ public sealed partial class MainWindowViewModel : ViewModelBase
 	private readonly IServiceProvider _serviceProvider;
 	private readonly IDialogService _dialogService;
 	private readonly IOptionsMonitor<UserConfiguration> _userConfigurationMonitor;
+	private readonly Stack<ViewModelBase> _navigationHistory = [];
 
 	private bool _initialized;
 
@@ -75,6 +77,7 @@ public MainWindowViewModel(IServiceProvider serviceProvider)
 		Initialize = commandFactory.Create(InitializeActiveViewAsync, () => !_initialized, "Initializing");
 		About = commandFactory.Create<Window>(ShowAboutWindow, "Waiting for About window to be closed");
 		License = commandFactory.Create<Window>(ShowLicenseWindow, "Waiting for License window to be closed");
+		NavigateBack = commandFactory.Create(NavigateBackAsync, () => _navigationHistory.Count is not 0, "Navigating back");
 
 		PropertyChanging += OnPropertyChanging;
 	}
@@ -88,6 +91,9 @@ public MainWindowViewModel(IServiceProvider serviceProvider)
 	/// <summary>Gets a command for showing <see cref="LicensesViewModel"/>.</summary>
 	public CommandBase License { get; }
 
+	/// <summary>Gets a command for switching to the previous <see cref="ActiveView"/>.</summary>
+	public CommandBase NavigateBack { get; }
+
 	/// <summary>Gets a value indicating whether it's possible to log out.</summary>
 	public bool CanLogOut => ActiveView is not null and not LoginViewModel and not ConfigurationWizardViewModel;
 
@@ -284,6 +290,11 @@ private Task SwitchTo<TViewModel>()
 			return Task.CompletedTask;
 		}
 
+		if (ActiveView is { } activeView and not (LoginViewModel or ConfigurationWizardViewModel))
+		{
+			_navigationHistory.Push(activeView);
+		}
+
 		var viewModel = _serviceProvider.GetRequiredService<TViewModel>();
 		ActiveView = viewModel;
 		return viewModel.RefreshAsync();
@@ -305,6 +316,19 @@ private async Task ShowLicenseWindow(Window window)
 		await _dialogService.ShowDialog(window, viewModel, dialog => dialog.Title = "Licenses");
 	}
 
+	private async Task NavigateBackAsync()
+	{
+		var viewModel = _navigationHistory.Pop();
+		if (ActiveView == viewModel)
+		{
+			return;
+		}
+
+		ActiveView = viewModel;
+		await viewModel.RefreshAsync();
+		NavigateBack.InvokeExecuteChanged();
+	}
+
 	private async void OnUserLoggedIn(object? sender, EventArgs e)
 	{
 		await SwitchToTransactionOverviewAsync();

source/Gnomeshade.Desktop/Views/MainWindow.axaml

@@ -124,6 +124,16 @@
 				<ProgressBar IsIndeterminate="{Binding IsBusy}" />
 			</StackPanel>
 		</Grid>
+
+		<Interaction.Behaviors>
+			<interactivity:PointerReleasedTrigger MouseButton="XButton1" SourceInteractive="{Binding $parent[Window]}">
+				<InvokeCommandAction Command="{Binding NavigateBack}" />
+			</interactivity:PointerReleasedTrigger>
+			<interactivity:HotKeyBehaviour
+				TopLevel="{Binding $parent[TopLevel]}"
+				HotKey="Alt+Left"
+				Command="{Binding NavigateBack}" />
+		</Interaction.Behaviors>
 	</Panel>
 
 	<Interaction.Behaviors>

tests/Gnomeshade.Avalonia.Core.Tests/MainWindowViewModelTests.cs

@@ -0,0 +1,80 @@
+// Copyright 2021 Valters Melnalksnis
+// Licensed under the GNU Affero General Public License v3.0 or later.
+// See LICENSE.txt file in the project root for full license information.
+
+using System.Threading.Tasks;
+
+using Gnomeshade.Avalonia.Core.Configuration;
+using Gnomeshade.Avalonia.Core.Counterparties;
+using Gnomeshade.Avalonia.Core.DesignTime;
+using Gnomeshade.Avalonia.Core.Products;
+using Gnomeshade.Avalonia.Core.Transactions;
+
+namespace Gnomeshade.Avalonia.Core.Tests;
+
+[TestOf(typeof(MainWindowViewModel))]
+public sealed class MainWindowViewModelTests
+{
+	[Test]
+	public async Task NavigateBack()
+	{
+		var viewModel = DesignTimeData.MainWindowViewModel;
+
+		viewModel.Initialize.Execute(null);
+		while (viewModel.IsBusy)
+		{
+			await Task.Delay(100);
+		}
+
+		using (new AssertionScope())
+		{
+			viewModel.ActiveView.Should().BeOfType<ConfigurationWizardViewModel>("configuration should not be valid");
+			viewModel.NavigateBack.CanExecute(null).Should().BeFalse();
+		}
+
+		await viewModel.SwitchToTransactionOverviewAsync();
+		using (new AssertionScope())
+		{
+			viewModel.ActiveView.Should().BeOfType<TransactionViewModel>();
+			viewModel.NavigateBack.CanExecute(null).Should().BeFalse();
+		}
+
+		await viewModel.SwitchToCategoriesAsync();
+		using (new AssertionScope())
+		{
+			viewModel.ActiveView.Should().BeOfType<CategoryViewModel>();
+			viewModel.NavigateBack.CanExecute(null).Should().BeTrue();
+		}
+
+		await viewModel.SwitchToCounterpartiesAsync();
+		using (new AssertionScope())
+		{
+			viewModel.ActiveView.Should().BeOfType<CounterpartyViewModel>();
+			viewModel.NavigateBack.CanExecute(null).Should().BeTrue();
+		}
+
+		viewModel.NavigateBack.Execute(null);
+		while (viewModel.IsBusy)
+		{
+			await Task.Delay(100);
+		}
+
+		using (new AssertionScope())
+		{
+			viewModel.ActiveView.Should().BeOfType<CategoryViewModel>();
+			viewModel.NavigateBack.CanExecute(null).Should().BeTrue();
+		}
+
+		viewModel.NavigateBack.Execute(null);
+		while (viewModel.IsBusy)
+		{
+			await Task.Delay(100);
+		}
+
+		using (new AssertionScope())
+		{
+			viewModel.NavigateBack.CanExecute(null).Should().BeFalse();
+			viewModel.ActiveView.Should().BeOfType<TransactionViewModel>();
+		}
+	}
+}