add Recommendation

src/Shared/HandyControlDemo_Shared/ViewModel/Main/ContributorsViewModel.cs

@@ -1,24 +0,0 @@
-using System.Threading.Tasks;
-using HandyControlDemo.Data;
-using HandyControlDemo.Service;
-
-namespace HandyControlDemo.ViewModel
-{
-    public class ContributorsViewModel : DemoViewModelBase<ContributorModel>
-    {
-        public ContributorsViewModel(DataService dataService)
-        {
-#if netle40
-            Task.Factory.StartNew(() =>
-            {
-                DataList = dataService.GetContributorDataList();
-            });
-#else
-            Task.Run(() =>
-            {
-                DataList = dataService.GetContributorDataList();
-            });
-#endif
-        }
-    }
-}

src/Shared/HandyControlDemo_Shared/ViewModel/Main/ItemsDisplayViewModel.cs

@@ -0,0 +1,19 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using HandyControlDemo.Data;
+
+namespace HandyControlDemo.ViewModel
+{
+    public class ItemsDisplayViewModel : DemoViewModelBase<AvatarModel>
+    {
+        public ItemsDisplayViewModel(Func<List<AvatarModel>> getDatAction)
+        {
+#if netle40
+            Task.Factory.StartNew(() => DataList = getDatAction?.Invoke());
+#else
+            Task.Run(() => DataList = getDatAction?.Invoke());
+#endif
+        }
+    }
+}

src/Shared/HandyControlDemo_Shared/ViewModel/Main/NoUserViewModel.cs

@@ -0,0 +1,22 @@
+using System;
+using GalaSoft.MvvmLight;
+using GalaSoft.MvvmLight.CommandWpf;
+using GalaSoft.MvvmLight.Messaging;
+using HandyControlDemo.Data;
+using HandyControlDemo.Tools;
+
+namespace HandyControlDemo.ViewModel
+{
+    public class NoUserViewModel : ViewModelBase
+    {
+        public RelayCommand<string> OpenViewCmd => new Lazy<RelayCommand<string>>(() =>
+            new RelayCommand<string>(OpenView)).Value;
+
+        private void OpenView(string viewName)
+        {
+            Messenger.Default.Send<object>(null, MessageToken.ClearLeftSelected);
+            Messenger.Default.Send(true, MessageToken.FullSwitch);
+            Messenger.Default.Send(AssemblyHelper.CreateInternalInstance($"UserControl.{viewName}"), MessageToken.LoadShowContent);
+        }
+    }
+}