From 19d2a4ab947f807b68a5d2cda5c68b6bfa0a5d17 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jonas=20=C3=85dahl?= <jadahl@gmail.com>
Date: Thu, 3 Dec 2020 22:50:31 +0100
Subject: [PATCH] gtk/window: Only fake motion events on windows with pending
 allocations

This fixes an issue where the focus of the window continuously received
fake motion events even when a popover was open, making input events end
up behind the popover.

It also adds a comment describing why motion events are requested. Note
that popovers won't work with this, and it's possible both in the past
and now that sporadic missplaced motion events will appear, e.g. when a
window changes allocation but a popover is open.
---
 gtk/gtkwindow.c | 32 ++++++++++++++++++++------------
 1 file changed, 20 insertions(+), 12 deletions(-)

diff --git a/gtk/gtkwindow.c b/gtk/gtkwindow.c
index 2ffc166894..07c23b0761 100644
--- a/gtk/gtkwindow.c
+++ b/gtk/gtkwindow.c
@@ -1894,7 +1894,6 @@ gtk_window_native_layout (GtkNative *native,
   GtkWindow *window = GTK_WINDOW (native);
   GtkWindowPrivate *priv = gtk_window_get_instance_private (window);
   GtkWidget *widget = GTK_WIDGET (native);
-  GdkSeat *seat;
 
   if (priv->surface_width != width || priv->surface_height != height)
     {
@@ -1903,21 +1902,30 @@ gtk_window_native_layout (GtkNative *native,
       priv->surface_height = height;
     }
 
-  seat = gdk_display_get_default_seat (gtk_widget_get_display (widget));
-  if (seat)
+  /* This fake motion event is needed for getting up to date pointer focus
+   * and coordinates when tho pointer didn't move but the layout changed
+   * within the window.
+   */
+  if (gtk_widget_needs_allocate (widget))
     {
-      GdkDevice *device;
-      GtkWidget *focus;
+      GdkSeat *seat;
 
-      device = gdk_seat_get_pointer (seat);
-      focus = gtk_window_lookup_pointer_focus_widget (GTK_WINDOW (widget),
-                                                      device, NULL);
-      if (focus)
+      seat = gdk_display_get_default_seat (gtk_widget_get_display (widget));
+      if (seat)
         {
-          GdkSurface *focus_surface =
-            gtk_native_get_surface (gtk_widget_get_native (focus));
+          GdkDevice *device;
+          GtkWidget *focus;
 
-          gdk_surface_request_motion (focus_surface);
+          device = gdk_seat_get_pointer (seat);
+          focus = gtk_window_lookup_pointer_focus_widget (GTK_WINDOW (widget),
+                                                          device, NULL);
+          if (focus)
+            {
+              GdkSurface *focus_surface =
+                gtk_native_get_surface (gtk_widget_get_native (focus));
+
+              gdk_surface_request_motion (focus_surface);
+            }
         }
     }