Adjust project structure

src/Shared/HandyControl_Shared/Tools/Extension/DialogExtension.cs

@@ -0,0 +1,78 @@
+using System;
+using System.Threading.Tasks;
+using System.Windows;
+using HandyControl.Controls;
+
+namespace HandyControl.Tools.Extension
+{
+    public interface IDialogResultable<T>
+    {
+        T Result { get; set; }
+
+        Action CloseAction { get; set; }
+    }
+
+    public static class DialogExtension
+    {
+        public static Task<TResult> GetResultAsync<TResult>(this Dialog dialog)
+        {
+            var tcs = new TaskCompletionSource<TResult>();
+
+            try
+            {
+                if (dialog.IsClosed)
+                {
+                    SetResult();
+                }
+                else
+                {
+                    dialog.Unloaded += OnUnloaded;
+                    dialog.GetViewModel<IDialogResultable<TResult>>().CloseAction = dialog.Close;
+                }
+            }
+            catch (Exception e)
+            {
+                tcs.TrySetException(e);
+            }
+
+            return tcs.Task;
+
+            // ReSharper disable once ImplicitlyCapturedClosure
+            void OnUnloaded(object sender, RoutedEventArgs args)
+            {
+                dialog.Unloaded -= OnUnloaded;
+                SetResult();
+            }
+
+            void SetResult()
+            {
+                try
+                {
+                    tcs.TrySetResult(dialog.GetViewModel<IDialogResultable<TResult>>().Result);
+                }
+                catch (Exception e)
+                {
+                    tcs.TrySetException(e);
+                }
+            }
+        }
+
+        public static Dialog Initialize<TViewModel>(this Dialog dialog, Action<TViewModel> configure)
+        {
+            configure?.Invoke(dialog.GetViewModel<TViewModel>());
+
+            return dialog;
+        }
+
+        public static TViewModel GetViewModel<TViewModel>(this Dialog dialog)
+        {
+            if (!(dialog.Content is FrameworkElement frameworkElement))
+                throw new InvalidOperationException("The dialog is not a derived class of the FrameworkElement. ");
+
+            if (!(frameworkElement.DataContext is TViewModel viewModel))
+                throw new InvalidOperationException($"The view model of the dialog is not the {typeof(TViewModel)} type or its derived class. ");
+
+            return viewModel;
+        }
+    }
+}