Merge pull request #58 from DingpingZhang/enhance-dialog

添加“Dialog.ShowAsync<T>(): T”函数以获得Dialog的返回值

HandyControlDemo/ViewModel/Controls/DialogDemoViewModel.cs

@@ -1,13 +1,25 @@
 using System;
+using System.Threading.Tasks;
 using GalaSoft.MvvmLight;
 using GalaSoft.MvvmLight.CommandWpf;
 using HandyControl.Controls;
+using HandyControl.Tools.Extension;
 using HandyControlDemo.UserControl;
+using HandyControlDemo.UserControl.Basic;
+using HandyControlDemo.ViewModel.Basic;
 
 namespace HandyControlDemo.ViewModel
 {
     public class DialogDemoViewModel : ViewModelBase
     {
+        private string _dialogResult;
+
+        public string DialogResult
+        {
+            get => _dialogResult;
+            set => Set(ref _dialogResult, value);
+        }
+
         public RelayCommand ShowTextCmd => new Lazy<RelayCommand>(() =>
             new RelayCommand(ShowText)).Value;
 
@@ -15,5 +27,15 @@ namespace HandyControlDemo.ViewModel
         {
             Dialog.Show(new TextDialog());
         }
+
+        public RelayCommand ShowInteractiveDialogCmd => new Lazy<RelayCommand>(() =>
+            new RelayCommand(async () => await ShowInteractiveDialog())).Value;
+
+        private async Task ShowInteractiveDialog()
+        {
+            DialogResult = await Dialog.Show<InteractiveDialog>()
+                .Initialize<InteractiveDialogViewModel>(vm => vm.Message = DialogResult)
+                .GetResultAsync<string>();
+        }
     }
 }