add SearchBar, Shield, SideMenu and SimpleItemsControl docs

doc/source/handycontrol/extend_controls/simpleItemsControl/index.md

@@ -1,5 +1,22 @@
 ---
-title: 建设中
+title: SimpleItemsControl 简单项目控件
 ---
 
-建设中
+一种轻量级ItemsControl控件.
+
+```cs
+[DefaultProperty("Items")]
+[ContentProperty("Items")]
+[TemplatePart(Name = ElementPanel, Type = typeof(Panel))]
+public class SimpleItemsControl : Control
+```
+
+# 属性
+
+|属性|描述|默认值|备注|
+|-|-|-|-|
+|ItemTemplate|项目模板|||
+|ItemContainerStyle|项目容器样式|||
+|ItemsSource|项目资源|||
+|Items|项目|||
+|HasItems|是否有项目|false||