Added in generic ViewModel

2026-04-06 19:26:39 +02:00 · 2020-03-11 10:43:32 -07:00
parent e2c7941542
commit 3f5a54f9f1
43 changed files with 1305 additions and 23 deletions
--- a/src/core/Microsoft.PowerToys.Settings.UI/ViewModels/ShellViewModel.cs
+++ b/src/core/Microsoft.PowerToys.Settings.UI/ViewModels/ShellViewModel.cs
@@ -0,0 +1,121 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using System.Windows.Input;
+
+using Microsoft.PowerToys.Settings.UI.Helpers;
+using Microsoft.PowerToys.Settings.UI.Services;
+
+using Windows.System;
+using Windows.UI.Xaml.Controls;
+using Windows.UI.Xaml.Input;
+using Windows.UI.Xaml.Navigation;
+
+using WinUI = Microsoft.UI.Xaml.Controls;
+
+namespace Microsoft.PowerToys.Settings.UI.ViewModels
+{
+    public class ShellViewModel : Observable
+    {
+        private readonly KeyboardAccelerator _altLeftKeyboardAccelerator = BuildKeyboardAccelerator(VirtualKey.Left, VirtualKeyModifiers.Menu);
+        private readonly KeyboardAccelerator _backKeyboardAccelerator = BuildKeyboardAccelerator(VirtualKey.GoBack);
+
+        private bool _isBackEnabled;
+        private IList<KeyboardAccelerator> _keyboardAccelerators;
+        private WinUI.NavigationView _navigationView;
+        private WinUI.NavigationViewItem _selected;
+        private ICommand _loadedCommand;
+        private ICommand _itemInvokedCommand;
+
+        public bool IsBackEnabled
+        {
+            get { return _isBackEnabled; }
+            set { Set(ref _isBackEnabled, value); }
+        }
+
+        public WinUI.NavigationViewItem Selected
+        {
+            get { return _selected; }
+            set { Set(ref _selected, value); }
+        }
+
+        public ICommand LoadedCommand => _loadedCommand ?? (_loadedCommand = new RelayCommand(OnLoaded));
+
+        public ICommand ItemInvokedCommand => _itemInvokedCommand ?? (_itemInvokedCommand = new RelayCommand<WinUI.NavigationViewItemInvokedEventArgs>(OnItemInvoked));
+
+        public ShellViewModel()
+        {
+        }
+
+        public void Initialize(Frame frame, WinUI.NavigationView navigationView, IList<KeyboardAccelerator> keyboardAccelerators)
+        {
+            _navigationView = navigationView;
+            _keyboardAccelerators = keyboardAccelerators;
+            NavigationService.Frame = frame;
+            NavigationService.NavigationFailed += Frame_NavigationFailed;
+            NavigationService.Navigated += Frame_Navigated;
+            _navigationView.BackRequested += OnBackRequested;
+        }
+
+        private async void OnLoaded()
+        {
+            // Keyboard accelerators are added here to avoid showing 'Alt + left' tooltip on the page.
+            // More info on tracking issue https://github.com/Microsoft/microsoft-ui-xaml/issues/8
+            _keyboardAccelerators.Add(_altLeftKeyboardAccelerator);
+            _keyboardAccelerators.Add(_backKeyboardAccelerator);
+            await Task.CompletedTask;
+        }
+
+        private void OnItemInvoked(WinUI.NavigationViewItemInvokedEventArgs args)
+        {
+            var item = _navigationView.MenuItems
+                            .OfType<WinUI.NavigationViewItem>()
+                            .First(menuItem => (string)menuItem.Content == (string)args.InvokedItem);
+            var pageType = item.GetValue(NavHelper.NavigateToProperty) as Type;
+            NavigationService.Navigate(pageType);
+        }
+
+        private void OnBackRequested(WinUI.NavigationView sender, WinUI.NavigationViewBackRequestedEventArgs args)
+        {
+            NavigationService.GoBack();
+        }
+
+        private void Frame_NavigationFailed(object sender, NavigationFailedEventArgs e)
+        {
+            throw e.Exception;
+        }
+
+        private void Frame_Navigated(object sender, NavigationEventArgs e)
+        {
+            IsBackEnabled = NavigationService.CanGoBack;
+            Selected = _navigationView.MenuItems
+                            .OfType<WinUI.NavigationViewItem>()
+                            .FirstOrDefault(menuItem => IsMenuItemForPageType(menuItem, e.SourcePageType));
+        }
+
+        private bool IsMenuItemForPageType(WinUI.NavigationViewItem menuItem, Type sourcePageType)
+        {
+            var pageType = menuItem.GetValue(NavHelper.NavigateToProperty) as Type;
+            return pageType == sourcePageType;
+        }
+
+        private static KeyboardAccelerator BuildKeyboardAccelerator(VirtualKey key, VirtualKeyModifiers? modifiers = null)
+        {
+            var keyboardAccelerator = new KeyboardAccelerator() { Key = key };
+            if (modifiers.HasValue)
+            {
+                keyboardAccelerator.Modifiers = modifiers.Value;
+            }
+
+            keyboardAccelerator.Invoked += OnKeyboardAcceleratorInvoked;
+            return keyboardAccelerator;
+        }
+
+        private static void OnKeyboardAcceleratorInvoked(KeyboardAccelerator sender, KeyboardAcceleratorInvokedEventArgs args)
+        {
+            var result = NavigationService.GoBack();
+            args.Handled = result;
+        }
+    }
+}