添加子分区的选中项管理

src/App/Pages/Overlay/PartitionDetailPage.xaml

@@ -36,11 +36,15 @@
             IsBackButtonVisible="Collapsed"
             IsPaneToggleButtonVisible="False"
             IsSettingsVisible="False"
+            ItemInvoked="OnDetailNavigationViewItemInvoked"
             MenuItemsSource="{x:Bind ViewModel.SubPartitionCollection}"
             PaneDisplayMode="Top">
+            <muxc:NavigationView.Resources>
+                <SolidColorBrush x:Key="NavigationViewContentBackground" Color="Transparent" />
+            </muxc:NavigationView.Resources>
             <muxc:NavigationView.MenuItemTemplate>
                 <DataTemplate x:DataType="uwp:SubPartitionViewModel">
-                    <muxc:NavigationViewItem Content="{x:Bind Title, Mode=OneWay}" />
+                    <muxc:NavigationViewItem Content="{x:Bind Title, Mode=OneWay}" Tag="{x:Bind SubPartitionId}" />
                 </DataTemplate>
             </muxc:NavigationView.MenuItemTemplate>
         </muxc:NavigationView>

src/App/Pages/Overlay/PartitionDetailPage.xaml.cs

 // Copyright (c) Richasy. All rights reserved.
 
+using System;
+using System.ComponentModel;
+using System.Linq;
 using Richasy.Bili.App.Resources.Extension;
 using Richasy.Bili.ViewModels.Uwp;
 using Windows.UI.Xaml;
@@ -26,6 +29,8 @@ namespace Richasy.Bili.App.Pages.Overlay
         public PartitionDetailPage()
         {
             this.InitializeComponent();
+            this.Loaded += this.OnLoaded;
+            this.Unloaded += this.OnUnloaded;
         }
 
         /// <summary>
@@ -57,5 +62,53 @@ namespace Richasy.Bili.App.Pages.Overlay
             var animate = animationService.PrepareToAnimate("PartitionBackAnimate", this.PartitionHeader);
             animate.Configuration = new DirectConnectedAnimationConfiguration();
         }
+
+        private void OnUnloaded(object sender, RoutedEventArgs e)
+        {
+            ViewModel.PropertyChanged -= OnViewModelPropertyChanged;
+        }
+
+        private void OnLoaded(object sender, RoutedEventArgs e)
+        {
+            ViewModel.PropertyChanged += OnViewModelPropertyChanged;
+            CheckCurrentSubPartition();
+        }
+
+        private void OnViewModelPropertyChanged(object sender, PropertyChangedEventArgs e)
+        {
+            if (e.PropertyName == nameof(ViewModel.CurrentSelectedSubPartition))
+            {
+                CheckCurrentSubPartition();
+            }
+        }
+
+        private void OnDetailNavigationViewItemInvoked(Microsoft.UI.Xaml.Controls.NavigationView sender, Microsoft.UI.Xaml.Controls.NavigationViewItemInvokedEventArgs args)
+        {
+            var invokeItem = args.InvokedItemContainer as Microsoft.UI.Xaml.Controls.NavigationViewItem;
+            var subPartitionId = invokeItem.Tag == null ? -1 : Convert.ToInt32(invokeItem.Tag);
+            SubPartitionViewModel vm;
+            if (subPartitionId == -1)
+            {
+                vm = ViewModel.SubPartitionCollection.First();
+            }
+            else
+            {
+                vm = ViewModel.SubPartitionCollection.Where(p => p.SubPartitionId == subPartitionId).FirstOrDefault();
+            }
+
+            ViewModel.CurrentSelectedSubPartition = vm;
+        }
+
+        private void CheckCurrentSubPartition()
+        {
+            var vm = ViewModel.CurrentSelectedSubPartition;
+            if (vm != null)
+            {
+                if (!(DetailNavigationView.SelectedItem is SubPartitionViewModel selectedItem) || selectedItem != vm)
+                {
+                    DetailNavigationView.SelectedItem = vm;
+                }
+            }
+        }
     }
 }

src/ViewModels/ViewModels.Uwp/PartitionViewModel/PartitionViewModel.Properties.cs

@@ -35,6 +35,12 @@ namespace Richasy.Bili.ViewModels.Uwp
         /// </summary>
         public int PartitionId => _partition?.Tid ?? 0;
 
+        /// <summary>
+        /// 当前选中的子分区.
+        /// </summary>
+        [Reactive]
+        public SubPartitionViewModel CurrentSelectedSubPartition { get; set; }
+
         /// <inheritdoc/>
         public override bool Equals(object obj) => obj is PartitionViewModel model && PartitionId == model.PartitionId;
 

src/ViewModels/ViewModels.Uwp/PartitionViewModel/PartitionViewModel.cs

 // Copyright (c) Richasy. All rights reserved.
 
 using System.Collections.ObjectModel;
+using System.Linq;
 using Richasy.Bili.Models.BiliBili;
 
 namespace Richasy.Bili.ViewModels.Uwp
@@ -35,6 +36,8 @@ namespace Richasy.Bili.ViewModels.Uwp
             {
                 this.SubPartitionCollection.Insert(0, new SubPartitionViewModel(null));
             }
+
+            this.CurrentSelectedSubPartition = this.SubPartitionCollection.First();
         }
     }
 }