Fix: Fixed crash that would occur when adding a new tab (#12840)

Author: hishitetsu

src/Files.App/UserControls/InnerNavigationToolbar.xaml

@@ -443,7 +443,7 @@
 				x:Name="SelectionOptions"
 				Width="Auto"
 				MinWidth="40"
-				x:Load="{x:Bind ViewModel.InstanceViewModel.IsPageTypeNotHome, Mode=OneWay}"
+				x:Load="{x:Bind ShowViewControlButton, Mode=OneWay}"
 				AccessKey="S"
 				AutomationProperties.Name="{helpers:ResourceString Name=SelectionOptions}"
 				Label="{helpers:ResourceString Name=NavToolbarSelectionOptions/Label}"
@@ -486,7 +486,7 @@
 				x:Name="ArrangementOptions"
 				Width="Auto"
 				MinWidth="40"
-				x:Load="{x:Bind ViewModel.InstanceViewModel.IsPageTypeNotHome, Mode=OneWay}"
+				x:Load="{x:Bind ShowViewControlButton, Mode=OneWay}"
 				AccessKey="A"
 				AutomationProperties.Name="{helpers:ResourceString Name=Sort}"
 				Label="{helpers:ResourceString Name=Sort}"
@@ -590,7 +590,7 @@
 				x:Name="LayoutOptionsButton"
 				Width="Auto"
 				MinWidth="40"
-				x:Load="{x:Bind ViewModel.InstanceViewModel.IsPageTypeNotHome, Mode=OneWay}"
+				x:Load="{x:Bind ShowViewControlButton, Mode=OneWay}"
 				AccessKey="L"
 				AutomationProperties.Name="{helpers:ResourceString Name=Layout}"
 				Label="{helpers:ResourceString Name=Layout}"

src/Files.App/UserControls/InnerNavigationToolbar.xaml.cs

@@ -40,6 +40,16 @@ public ToolbarViewModel ViewModel
 		public static readonly DependencyProperty ViewModelProperty =
 			DependencyProperty.Register(nameof(ViewModel), typeof(ToolbarViewModel), typeof(InnerNavigationToolbar), new PropertyMetadata(null));
 
+		public bool ShowViewControlButton
+		{
+			get { return (bool)GetValue(ShowViewControlButtonProperty); }
+			set { SetValue(ShowViewControlButtonProperty, value); }
+		}
+
+		// Using a DependencyProperty as the backing store for ShowViewControlButton.  This enables animation, styling, binding, etc...
+		public static readonly DependencyProperty ShowViewControlButtonProperty =
+			DependencyProperty.Register("ShowViewControlButton", typeof(bool), typeof(AddressToolbar), new PropertyMetadata(null));
+
 		public bool ShowPreviewPaneButton
 		{
 			get { return (bool)GetValue(ShowPreviewPaneButtonProperty); }

src/Files.App/Views/MainPage.xaml

@@ -218,6 +218,7 @@
 					x:Load="False"
 					Loaded="NavToolbar_Loaded"
 					ShowPreviewPaneButton="{x:Bind ShouldPreviewPaneBeDisplayed, Mode=OneWay}"
+					ShowViewControlButton="{x:Bind ShouldViewControlBeDisplayed, Mode=OneWay}"
 					TabIndex="2" />
 
 				<!--  Page Content  -->

src/Files.App/Views/MainPage.xaml.cs

@@ -484,6 +484,8 @@ private void PaneSplitter_ManipulationCompleted(object sender, ManipulationCompl
 			this.ChangeCursor(InputSystemCursor.Create(InputSystemCursorShape.Arrow));
 		}
 
+		public bool ShouldViewControlBeDisplayed => SidebarAdaptiveViewModel.PaneHolder?.ActivePane?.InstanceViewModel?.IsPageTypeNotHome ?? false;
+
 		public bool ShouldPreviewPaneBeActive => UserSettingsService.PreviewPaneSettingsService.IsEnabled && ShouldPreviewPaneBeDisplayed;
 
 		public bool ShouldPreviewPaneBeDisplayed
@@ -501,6 +503,7 @@ public bool ShouldPreviewPaneBeDisplayed
 
 		private void LoadPaneChanged()
 		{
+			OnPropertyChanged(nameof(ShouldViewControlBeDisplayed));
 			OnPropertyChanged(nameof(ShouldPreviewPaneBeActive));
 			OnPropertyChanged(nameof(ShouldPreviewPaneBeDisplayed));
 			UpdatePositioning();