feat: add JumpTo functionality in ApplicationViewModel and integrate with menu.

demo/Semi.Avalonia.Demo/App.axaml

@@ -20,6 +20,14 @@
             </ResourceDictionary.MergedDictionaries>
         </ResourceDictionary>
     </Application.Resources>
+    <NativeMenu.Menu>
+        <NativeMenu>
+            <NativeMenuItem
+                Header="About Us"
+                Command="{Binding JumpToCommand}"
+                CommandParameter="{Binding $self.Header}" />
+        </NativeMenu>
+    </NativeMenu.Menu>
     <TrayIcon.Icons>
         <TrayIcons>
             <TrayIcon
@@ -28,7 +36,13 @@
                 ToolTipText="Semi Avalonia Demo">
                 <TrayIcon.Menu>
                     <NativeMenu>
-                        <NativeMenuItem Header="Exit" Command="{Binding ExitCommand}" />
+                        <NativeMenuItem
+                            Header="About Us"
+                            Command="{Binding JumpToCommand}"
+                            CommandParameter="{Binding $self.Header}" />
+                        <NativeMenuItem
+                            Header="Exit"
+                            Command="{Binding ExitCommand}" />
                     </NativeMenu>
                 </TrayIcon.Menu>
             </TrayIcon>

demo/Semi.Avalonia.Demo/ViewModels/ApplicationViewModel.cs

@@ -2,11 +2,18 @@ using Avalonia;
 using Avalonia.Controls.ApplicationLifetimes;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
+using CommunityToolkit.Mvvm.Messaging;
 
 namespace Semi.Avalonia.Demo.ViewModels;
 
 public partial class ApplicationViewModel : ObservableObject
 {
+    [RelayCommand]
+    private void JumpTo(string header)
+    {
+        WeakReferenceMessenger.Default.Send(header, "JumpTo");
+    }
+
     [RelayCommand]
     private void Exit()
     {

demo/Semi.Avalonia.Demo/Views/MainView.axaml.cs

@@ -9,6 +9,7 @@ using Avalonia.Controls.ApplicationLifetimes;
 using Avalonia.Styling;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
+using CommunityToolkit.Mvvm.Messaging;
 
 namespace Semi.Avalonia.Demo.Views;
 
@@ -18,6 +19,19 @@ public partial class MainView : UserControl
     {
         InitializeComponent();
         this.DataContext = new MainViewModel();
+        WeakReferenceMessenger.Default.Register<string, string>(this, "JumpTo", MessageHandler);
+    }
+
+    private void MessageHandler(object _, string message)
+    {
+        foreach (var item in tab.ItemsView)
+        {
+            if (item is TabItem tabItem && tabItem.Header is not null && tabItem.Header.Equals(message))
+            {
+                tab.SelectedItem = tabItem;
+                break;
+            }
+        }
     }
 }