Merge pull request #877 from MrDaedra/master

Solved issue #92

src/Avalonia.Controls/Window.cs

@@ -11,6 +11,7 @@ using Avalonia.Media;
 using Avalonia.Platform;
 using Avalonia.Styling;
 using System.Collections.Generic;
+using System.Linq;
 
 namespace Avalonia.Controls
 {
@@ -268,6 +269,10 @@ namespace Avalonia.Controls
 
             using (BeginAutoSizing())
             {
+                var affectedWindows = s_windows.Where(w => w.IsEnabled && w != this).ToList();
+                var activated = affectedWindows.Where(w => w.IsActive).FirstOrDefault();
+                SetIsEnabled(affectedWindows, false);
+
                 var modal = PlatformImpl.ShowDialog();
                 var result = new TaskCompletionSource<TResult>();
 
@@ -276,6 +281,8 @@ namespace Avalonia.Controls
                     .Subscribe(_ =>
                     {
                         modal.Dispose();
+                        SetIsEnabled(affectedWindows, true);
+                        activated?.Activate();
                         result.SetResult((TResult)_dialogResult);
                     });
 
@@ -283,6 +290,14 @@ namespace Avalonia.Controls
             }
         }
 
+        void SetIsEnabled(IEnumerable<Window> windows, bool isEnabled)
+        {
+            foreach (var window in windows)
+            {
+                window.IsEnabled = isEnabled;
+            }
+        }
+
         /// <inheritdoc/>
         void INameScope.Register(string name, object element)
         {

src/Windows/Avalonia.Win32/WindowImpl.cs

@@ -33,7 +33,6 @@ namespace Avalonia.Win32
         private IntPtr _hwnd;
         private IInputRoot _owner;
         private bool _trackingMouse;
-        private bool _isActive;
         private bool _decorated = true;
         private double _scaling = 1;
         private WindowState _showWindowState;
@@ -344,30 +343,9 @@ namespace Avalonia.Win32
 
         public virtual IDisposable ShowDialog()
         {
-            var disabled = s_instances.Where(x => x != this && x.IsEnabled).ToList();
-            WindowImpl activated = null;
-
-            foreach (var window in disabled)
-            {
-                if (window._isActive)
-                {
-                    activated = window;
-                }
-
-                window.IsEnabled = false;
-            }
-
             Show();
 
-            return Disposable.Create(() =>
+            return Disposable.Empty;
-            {
-                foreach (var window in disabled)
-                {
-                    window.IsEnabled = true;
-                }
-
-                activated?.Activate();
-            });
         }
 
         public void SetCursor(IPlatformHandle cursor)
@@ -414,12 +392,10 @@ namespace Avalonia.Win32
                     {
                         case UnmanagedMethods.WindowActivate.WA_ACTIVE:
                         case UnmanagedMethods.WindowActivate.WA_CLICKACTIVE:
-                            _isActive = true;
                             Activated?.Invoke();
                             break;
 
                         case UnmanagedMethods.WindowActivate.WA_INACTIVE:
-                            _isActive = false;
                             Deactivated?.Invoke();
                             break;
                     }