From 22c5a5e6a1b0443488e5bddb037f1dece754e277 Mon Sep 17 00:00:00 2001
From: Steven Kirk <grokys@gmail.com>
Date: Thu, 16 May 2019 17:43:43 +0200
Subject: [PATCH 1/2] Fix usage of AddClassHandler in non-static ctor.

Property `AddClassHandler`s should only be added in static constructors. In this case it's not so important because `FocusManager` is a singleton, but best to fix the usage anyway.

Fixes #2315.
---
 src/Avalonia.Input/FocusManager.cs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/Avalonia.Input/FocusManager.cs b/src/Avalonia.Input/FocusManager.cs
index 102da6efc4..28fb26dca4 100644
--- a/src/Avalonia.Input/FocusManager.cs
+++ b/src/Avalonia.Input/FocusManager.cs
@@ -23,7 +23,7 @@ namespace Avalonia.Input
         /// <summary>
         /// Initializes a new instance of the <see cref="FocusManager"/> class.
         /// </summary>
-        public FocusManager()
+        static FocusManager()
         {
             InputElement.PointerPressedEvent.AddClassHandler(
                 typeof(IInputElement),
@@ -174,7 +174,7 @@ namespace Avalonia.Input
         /// </summary>
         /// <param name="sender">The event sender.</param>
         /// <param name="e">The event args.</param>
-        private void OnPreviewPointerPressed(object sender, RoutedEventArgs e)
+        private static void OnPreviewPointerPressed(object sender, RoutedEventArgs e)
         {
             var ev = (PointerPressedEventArgs)e;
 
@@ -191,7 +191,7 @@ namespace Avalonia.Input
 
                 if (element != null)
                 {
-                    Focus(element, NavigationMethod.Pointer, ev.InputModifiers);
+                    Instance?.Focus(element, NavigationMethod.Pointer, ev.InputModifiers);
                 }
             }
         }

From fb08f031094c8904855c1b474bf64a2dd9c3ac34 Mon Sep 17 00:00:00 2001
From: Steven Kirk <grokys@gmail.com>
Date: Thu, 16 May 2019 17:44:26 +0200
Subject: [PATCH 2/2] Add a note to fix usage of AddClassHandler.

I plan on replacing DevTools with something newer soon, so just add a FIXME comment for now.
---
 src/Avalonia.Diagnostics/ViewModels/EventTreeNode.cs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Avalonia.Diagnostics/ViewModels/EventTreeNode.cs b/src/Avalonia.Diagnostics/ViewModels/EventTreeNode.cs
index 59c0f82414..7ece790310 100644
--- a/src/Avalonia.Diagnostics/ViewModels/EventTreeNode.cs
+++ b/src/Avalonia.Diagnostics/ViewModels/EventTreeNode.cs
@@ -56,6 +56,7 @@ namespace Avalonia.Diagnostics.ViewModels
         {
             if (IsEnabled.GetValueOrDefault() && !_isRegistered)
             {
+                // FIXME: This leaks event handlers.
                 _event.AddClassHandler(typeof(object), HandleEvent, (RoutingStrategies)7, handledEventsToo: true);
                 _isRegistered = true;
             }