add:浮动栏自定义

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

@@ -0,0 +1,26 @@
+using System.Windows.Input;
+
+namespace Ink_Canvas.Controls.Toolbar.Items
+{
+    /// <summary>
+    /// 清空按钮。位置：夹在颜色面板与 StackPanelCanvasControls 之间，
+    /// 所以用 BeforeAnchor 锚到 StackPanelCanvasControls。
+    /// </summary>
+    internal sealed class ClearToolItem : ToolbarImageButtonItemBase
+    {
+        public override string Id => "builtin.clear";
+        public override string LocalizationKey => "FloatingBar_Clear";
+        public override ToolbarSlot DefaultSlot => ToolbarSlot.FloatingBarMain;
+        public override int DefaultOrder => 0;
+        public override ToolbarInsertPosition DefaultPosition => ToolbarInsertPosition.BeforeAnchor;
+        public override string DefaultAnchorName => "StackPanelCanvasControls";
+
+        protected override string IconBrushResourceKey => "RedBrush";
+
+        protected override void OnClick(IToolbarHost host, object sender, MouseButtonEventArgs e)
+            => host.Window.SymbolIconDelete_MouseUp(sender, e);
+
+        protected override void AfterBuild(IToolbarHost host, ToolbarImageButton view)
+            => host.Window.AttachSymbolIconDelete(view);
+    }
+}