add partial codes

src/Shared/HandyControlDemo_Shared/UserControl/Controls/PropertyGridDemoCtl.xaml

@@ -0,0 +1,7 @@
+<UserControl x:Class="HandyControlDemo.UserControl.PropertyGridDemoCtl"
+             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             xmlns:userControl="clr-namespace:HandyControlDemo.UserControl"
+             Background="{DynamicResource RegionBrush}">
+    <userControl:UnderConstruction/>
+</UserControl>

src/Shared/HandyControlDemo_Shared/UserControl/Controls/PropertyGridDemoCtl.xaml.cs

@@ -0,0 +1,10 @@
+namespace HandyControlDemo.UserControl
+{
+    public partial class PropertyGridDemoCtl
+    {
+        public PropertyGridDemoCtl()
+        {
+            InitializeComponent();
+        }
+    }
+}