Improve popup positioning when using ThemeShadowChrome

Kinnara · Apr 28, 2020 · 8a3771d · 8a3771d
1 parent 4c023d1
commit 8a3771d
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Showing 6 changed files with 907 additions and 17 deletions.
diff --git a/Directory.Build.props b/Directory.Build.props
@@ -1,6 +1,6 @@
 <Project>
   <PropertyGroup>
-    <Version>0.9.0-preview.200425.2</Version>
+    <Version>0.9.0-preview.200428.1</Version>
     <Authors>Yimeng Wu</Authors>
     <Product>ModernWPF UI Library</Product>
     <PackageLicenseExpression>MIT</PackageLicenseExpression>

diff --git a/ModernWpf.Controls/Common/PopupHelper.cs b/ModernWpf.Controls/Common/PopupHelper.cs
@@ -1,6 +1,6 @@
 using System;
-using System.Reflection;
 using System.Windows.Controls.Primitives;
+using ModernWpf.Controls.Primitives;
 
 namespace ModernWpf.Controls
 {
@@ -13,32 +13,37 @@ public static void Reposition(this Popup popup)
                 throw new ArgumentNullException(nameof(popup));
             }
 
-            if (s_repositionDelegate == null && !s_failedToCreateRepositionDelegate)
+            if (PopupPositioner.GetPositioner(popup) is { } positioner)
             {
-                try
+                positioner.Reposition();
+            }
+            else
+            {
+                if (s_reposition.Value is { } reposition)
                 {
-                    var method = typeof(Popup).GetMethod("Reposition", BindingFlags.Instance | BindingFlags.NonPublic);
-                    s_repositionDelegate = (Action<Popup>)Delegate.CreateDelegate(typeof(Action<Popup>), method);
+                    reposition(popup);
                 }
-                catch (Exception)
+                else
                 {
-                    s_failedToCreateRepositionDelegate = true;
+                    var offset = popup.HorizontalOffset;
+                    popup.SetCurrentValue(Popup.HorizontalOffsetProperty, offset + 0.1);
+                    popup.InvalidateProperty(Popup.HorizontalOffsetProperty);
                 }
             }
+        }
 
-            if (s_repositionDelegate != null)
+        private static Action<Popup> CreateRepositionDelegate()
+        {
+            try
             {
-                s_repositionDelegate(popup);
+                return DelegateHelper.CreateDelegate<Action<Popup>>(typeof(Popup), nameof(Reposition), true);
             }
-            else
+            catch
             {
-                var offset = popup.HorizontalOffset;
-                popup.SetCurrentValue(Popup.HorizontalOffsetProperty, offset + 0.1);
-                popup.SetCurrentValue(Popup.HorizontalOffsetProperty, offset);
+                return null;
             }
         }
 
-        private static Action<Popup> s_repositionDelegate;
-        private static bool s_failedToCreateRepositionDelegate;
+        private static readonly Lazy<Action<Popup>> s_reposition = new Lazy<Action<Popup>>(CreateRepositionDelegate);
     }
 }