add style and demo

src/Shared/HandyControlDemo_Shared/ViewModel/Controls/SplitButtonDemoViewModel.cs

@@ -0,0 +1,17 @@
+using System;
+using GalaSoft.MvvmLight;
+using HandyControl.Controls;
+#if netle40
+using GalaSoft.MvvmLight.Command;
+#else
+using GalaSoft.MvvmLight.CommandWpf;
+# endif
+
+namespace HandyControlDemo.ViewModel
+{
+    public class SplitButtonDemoViewModel : ViewModelBase
+    {
+        public RelayCommand<string> SelectCmd => new Lazy<RelayCommand<string>>(() =>
+            new RelayCommand<string>(str => Growl.Info(str))).Value;
+    }
+}

src/Shared/HandyControlDemo_Shared/ViewModel/ViewModelLocator.cs

@@ -39,6 +39,7 @@ namespace HandyControlDemo.ViewModel
             SimpleIoc.Default.Register<CardDemoViewModel>();
             SimpleIoc.Default.Register<SpriteDemoViewModel>();
             SimpleIoc.Default.Register<NotificationDemoViewModel>();
+            SimpleIoc.Default.Register<SplitButtonDemoViewModel>();
         }
 
         public static ViewModelLocator Instance => new Lazy<ViewModelLocator>(() =>
@@ -94,6 +95,8 @@ namespace HandyControlDemo.ViewModel
 
         public NotificationDemoViewModel NotificationDemo => ServiceLocator.Current.GetInstance<NotificationDemoViewModel>();
 
+        public SplitButtonDemoViewModel SplitButtonDemo => ServiceLocator.Current.GetInstance<SplitButtonDemoViewModel>();
+
         #endregion
     }
 }