completed basic function

src/Shared/HandyControl_Shared/Data/Enum/ExpandMode.cs

@@ -0,0 +1,25 @@
+namespace HandyControl.Data.Enum
+{
+    public enum ExpandMode
+    {
+        /// <summary>
+        ///     显示所有项，且不可折叠
+        /// </summary>
+        ShowAll,
+
+        /// <summary>
+        ///     最多只能显示一项，且不可折叠
+        /// </summary>
+        ShowOne,
+
+        /// <summary>
+        ///     类似ShowOne，但是控件的尺寸不随项的数量而改变
+        /// </summary>
+        Accordion,
+
+        /// <summary>
+        ///     没有任何限制
+        /// </summary>
+        Freedom
+    }
+}