[gtk/wip/otte/listmodel: 2/22] window: Add gtk_window_get_toplevels()

[Benjamin Otte <otte src gnome org>]

commit 3e3c4f1787fb8b48198287f29c5e9d3c78346b61
Author: Benjamin Otte <otte redhat com>
Date:   Mon Aug 27 08:37:16 2018 +0200

    window: Add gtk_window_get_toplevels()
    
    This one returns a list of all toplevel windows.

 docs/reference/gtk/gtk4-sections.txt |  1 +
 gtk/gtkwidget.c                      |  3 ++
 gtk/gtkwindow.c                      | 55 ++++++++++++++++++++++++++++++++----
 gtk/gtkwindow.h                      |  2 ++
 4 files changed, 55 insertions(+), 6 deletions(-)
---
diff --git a/docs/reference/gtk/gtk4-sections.txt b/docs/reference/gtk/gtk4-sections.txt
index dda37387e0..dbb179d3b1 100644
--- a/docs/reference/gtk/gtk4-sections.txt
+++ b/docs/reference/gtk/gtk4-sections.txt
@@ -4500,6 +4500,7 @@ gtk_window_set_destroy_with_parent
 gtk_window_set_display
 gtk_window_is_active
 gtk_window_is_maximized
+gtk_window_get_toplevels
 gtk_window_list_toplevels
 gtk_window_add_mnemonic
 gtk_window_remove_mnemonic
diff --git a/gtk/gtkwidget.c b/gtk/gtkwidget.c
index 7699887c7f..a6c56292d9 100644
--- a/gtk/gtkwidget.c
+++ b/gtk/gtkwidget.c
@@ -3109,6 +3109,9 @@ gtk_widget_unparent (GtkWidget *widget)
 
   _gtk_widget_update_parent_muxer (widget);
 
+  if (old_parent->priv->children_observer)
+    gtk_list_list_model_item_removed (old_parent->priv->children_observer, old_prev_sibling);
+
   if (toplevel)
     {
       _gtk_widget_propagate_hierarchy_changed (widget, toplevel);
diff --git a/gtk/gtkwindow.c b/gtk/gtkwindow.c
index 48620575d7..e2cc8525f6 100644
--- a/gtk/gtkwindow.c
+++ b/gtk/gtkwindow.c
@@ -520,7 +520,7 @@ static void gtk_window_style_updated (GtkWidget     *widget);
 static void gtk_surface_state_flags_changed (GtkWidget     *widget,
                                             GtkStateFlags  previous_state);
 
-static GSList      *toplevel_list = NULL;
+static GListStore  *toplevel_list = NULL;
 static guint        window_signals[LAST_SIGNAL] = { 0 };
 static GList       *default_icon_list = NULL;
 static gchar       *default_icon_name = NULL;
@@ -785,6 +785,9 @@ gtk_window_class_init (GtkWindowClass *klass)
   quark_gtk_window_icon_info = g_quark_from_static_string ("gtk-window-icon-info");
   quark_gtk_buildable_accels = g_quark_from_static_string ("gtk-window-buildable-accels");
 
+  if (toplevel_list == NULL)
+    toplevel_list = g_list_store_new (GTK_TYPE_WIDGET);
+
   gobject_class->constructed = gtk_window_constructed;
   gobject_class->dispose = gtk_window_dispose;
   gobject_class->finalize = gtk_window_finalize;
@@ -1911,7 +1914,6 @@ gtk_window_init (GtkWindow *window)
 
   g_object_ref_sink (window);
   priv->has_user_ref_count = TRUE;
-  toplevel_list = g_slist_prepend (toplevel_list, window);
   gtk_window_update_debugging ();
 
 #ifdef GDK_WINDOWING_X11
@@ -2001,6 +2003,9 @@ gtk_window_constructed (GObject *object)
       gtk_event_controller_set_propagation_phase (GTK_EVENT_CONTROLLER (priv->bubble_drag_gesture),
                                                   GTK_PHASE_BUBBLE);
     }
+
+  g_list_store_append (toplevel_list, window);
+  g_object_unref (window);
 }
 
 static void
@@ -3271,6 +3276,26 @@ gtk_window_get_modal (GtkWindow *window)
   return priv->modal;
 }
 
+/**
+ * gtk_window_get_toplevels:
+ *
+ * Returns a list of all existing toplevel windows.
+ *
+ * If you want to iterate through the list and perform actions involving
+ * callbacks that might destroy the widgets or add new ones, be aware that
+ * the list of toplevels will change and emit the "items-changed" signal.
+ *
+ * Returns: (element-type GtkWidget) (transfer none): the list of toplevel widgets
+ */
+GListModel *
+gtk_window_get_toplevels (void)
+{
+  if (toplevel_list == NULL)
+    toplevel_list = g_list_store_new (GTK_TYPE_WIDGET);
+
+  return G_LIST_MODEL (toplevel_list);
+}
+
 /**
  * gtk_window_list_toplevels:
  * 
@@ -3286,11 +3311,18 @@ gtk_window_get_modal (GtkWindow *window)
 GList*
 gtk_window_list_toplevels (void)
 {
+  GListModel *toplevels;
   GList *list = NULL;
-  GSList *slist;
+  guint i;
 
-  for (slist = toplevel_list; slist; slist = slist->next)
-    list = g_list_prepend (list, slist->data);
+  toplevels = gtk_window_get_toplevels ();
+
+  for (i = 0; i < g_list_model_get_n_items (toplevels); i++)
+    {
+      gpointer item = g_list_model_get_item (toplevels, i);
+      list = g_list_prepend (list, item);
+      g_object_unref (item);
+    }
 
   return list;
 }
@@ -5868,10 +5900,21 @@ gtk_window_destroy (GtkWidget *widget)
 {
   GtkWindow *window = GTK_WINDOW (widget);
   GtkWindowPrivate *priv = gtk_window_get_instance_private (window);
+  guint i;
 
   gtk_window_release_application (window);
 
-  toplevel_list = g_slist_remove (toplevel_list, window);
+  for (i = 0; i < g_list_model_get_n_items (G_LIST_MODEL (toplevel_list)); i++)
+    {
+      gpointer item = g_list_model_get_item (G_LIST_MODEL (toplevel_list), i);
+      if (item == window)
+        {
+          g_list_store_remove (toplevel_list, i);
+          break;
+        }
+      else
+        g_object_unref (item);
+    }
   gtk_window_update_debugging ();
 
   if (priv->transient_parent)
diff --git a/gtk/gtkwindow.h b/gtk/gtkwindow.h
index 96c0e75267..35143ab700 100644
--- a/gtk/gtkwindow.h
+++ b/gtk/gtkwindow.h
@@ -315,6 +315,8 @@ void       gtk_window_set_modal      (GtkWindow *window,
 GDK_AVAILABLE_IN_ALL
 gboolean   gtk_window_get_modal      (GtkWindow *window);
 GDK_AVAILABLE_IN_ALL
+GListModel *gtk_window_get_toplevels (void);
+GDK_AVAILABLE_IN_ALL
 GList*     gtk_window_list_toplevels (void);
 GDK_AVAILABLE_IN_ALL
 void       gtk_window_set_has_user_ref_count (GtkWindow *window,