misc: extract VMs.

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

@@ -0,0 +1,29 @@
+using System.Collections.ObjectModel;
+using Avalonia.Controls;
+using CommunityToolkit.Mvvm.ComponentModel;
+
+namespace Semi.Avalonia.Demo.ViewModels;
+
+public class SplitViewDemoViewModel : ObservableObject
+{
+    public ObservableCollection<string> Songs { get; set; } =
+    [
+        "320万年前",
+        "隐德来希",
+        "孔明",
+        "锦鲤卟噜噜",
+        "指鹿为马",
+        "热带季风Remix",
+        "加州梦境",
+        "渐近自由",
+        "世界所有的烂漫",
+    ];
+
+    public static ObservableCollection<SplitViewDisplayMode> DisplayModes { get; set; } =
+    [
+        SplitViewDisplayMode.Inline,
+        SplitViewDisplayMode.CompactInline,
+        SplitViewDisplayMode.Overlay,
+        SplitViewDisplayMode.CompactOverlay,
+    ];
+}