[gnome-klotski/arnaudb/wip/gtk4: 25/38] Fix size-allocate.

[Arnaud B. <arnaudb src gnome org>]

commit 4e808bf394381bac0aff1703f37d7833ea2a8111
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Fri Jul 31 17:38:07 2020 +0200

    Fix size-allocate.

 data/ui/klotski.ui      |  1 -
 src/klotski-window.vala | 18 ++++--------------
 2 files changed, 4 insertions(+), 15 deletions(-)
---
diff --git a/data/ui/klotski.ui b/data/ui/klotski.ui
index 91b34af..27f6752 100644
--- a/data/ui/klotski.ui
+++ b/data/ui/klotski.ui
@@ -314,7 +314,6 @@
     <!-- <initial-focus name=""/> -->
     <property name="width-request">600</property>
     <property name="height-request">400</property>
-    <signal name="size-allocate" handler="on_size_allocate"/>
     <signal name="map" handler="init_state_watcher"/>
     <signal name="destroy" handler="on_destroy"/>
     <child type="titlebar">
diff --git a/src/klotski-window.vala b/src/klotski-window.vala
index 4fdefee..086330b 100644
--- a/src/klotski-window.vala
+++ b/src/klotski-window.vala
@@ -633,12 +633,6 @@ private class KlotskiWindow : ApplicationWindow
     * * Window management callbacks
     \*/
 
-    [GtkCallback]
-    private void on_size_allocate (Allocation allocation)
-    {
-        update_window_state ();
-    }
-
     [GtkCallback]
     private inline void init_state_watcher ()
     {
@@ -647,6 +641,7 @@ private class KlotskiWindow : ApplicationWindow
             assert_not_reached ();
         surface = (Gdk.Toplevel) (!) nullable_surface;
         surface.notify ["state"].connect (on_window_state_event);
+        surface.size_changed.connect (on_size_changed);
     }
 
     private Gdk.Toplevel surface;
@@ -694,17 +689,12 @@ private class KlotskiWindow : ApplicationWindow
     * * manage window state
     \*/
 
-    private void update_window_state () // called on size-allocate
+    private inline void on_size_changed (Gdk.Surface _surface, int width, int height)
     {
         if (window_is_maximized || window_is_tiled || window_is_fullscreen)
             return;
-        int? _window_width = null;
-        int? _window_height = null;
-        get_size (out _window_width, out _window_height);
-        if (_window_width == null || _window_height == null)
-            return;
-        window_width = (!) _window_width;
-        window_height = (!) _window_height;
+        window_width  = width;
+        window_height = height;
     }
 
     private void save_window_state ()   // called on destroy