add:浮动栏自定义

Ink Canvas/Controls/Toolbar/Items/FoldToolItem.cs

@@ -0,0 +1,20 @@
+using System.Windows.Input;
+
+namespace Ink_Canvas.Controls.Toolbar.Items
+{
+    internal sealed class FoldToolItem : ToolbarImageButtonItemBase
+    {
+        public override string Id => "builtin.fold";
+        public override string LocalizationKey => "FloatingBar_Hide";
+        public override ToolbarSlot DefaultSlot => ToolbarSlot.FloatingBarEnd;
+        public override int DefaultOrder => 120;
+        public override ToolbarInsertPosition DefaultPosition => ToolbarInsertPosition.AfterAnchor;
+        public override string DefaultAnchorName => "FloatingBarEndSeparator";
+
+        protected override void OnClick(IToolbarHost host, object sender, MouseButtonEventArgs e)
+            => host.Window.FoldFloatingBar_MouseUp(sender, e);
+
+        protected override void AfterBuild(IToolbarHost host, ToolbarImageButton view)
+            => host.Window.AttachFoldIcon(view);
+    }
+}