[gtk/wip/matthiasc/listview-2: 137/179] listitem: Move position/item/selected tracking to widget

[Matthias Clasen <matthiasc src gnome org>]

commit 755da397bc873332c7bdd6b48bc4f42ba00b7978
Author: Benjamin Otte <otte redhat com>
Date:   Sun Nov 3 03:34:56 2019 +0100

    listitem: Move position/item/selected tracking to widget
    
    This way, we can ensure it's always there when we need it (before the
    item gets created) and gone when we don't (if some GC language holds on
    to the item after we've destroyed the widget).

 gtk/gtklistitem.c        | 71 ++++++++++++++----------------------------------
 gtk/gtklistitemprivate.h |  9 ------
 gtk/gtklistitemwidget.c  | 67 ++++++++++++++++++++++++++++++++++-----------
 3 files changed, 72 insertions(+), 75 deletions(-)
---
diff --git a/gtk/gtklistitem.c b/gtk/gtklistitem.c
index 79d3e12e78c..01db2cdac4c 100644
--- a/gtk/gtklistitem.c
+++ b/gtk/gtklistitem.c
@@ -98,11 +98,15 @@ gtk_list_item_get_property (GObject    *object,
       break;
 
     case PROP_ITEM:
-      g_value_set_object (value, self->item);
+      if (self->owner)
+        g_value_set_object (value, gtk_list_item_widget_get_item (self->owner));
       break;
 
     case PROP_POSITION:
-      g_value_set_uint (value, self->position);
+      if (self->owner)
+        g_value_set_uint (value, gtk_list_item_widget_get_position (self->owner));
+      else
+        g_value_set_uint (value, GTK_INVALID_LIST_POSITION);
       break;
 
     case PROP_SELECTABLE:
@@ -110,7 +114,10 @@ gtk_list_item_get_property (GObject    *object,
       break;
 
     case PROP_SELECTED:
-      g_value_set_boolean (value, self->selected);
+      if (self->owner)
+        g_value_set_boolean (value, gtk_list_item_widget_get_selected (self->owner));
+      else
+        g_value_set_boolean (value, FALSE);
       break;
 
     default:
@@ -259,7 +266,10 @@ gtk_list_item_get_item (GtkListItem *self)
 {
   g_return_val_if_fail (GTK_IS_LIST_ITEM (self), NULL);
 
-  return self->item;
+  if (self->owner == NULL)
+    return NULL;
+
+  return gtk_list_item_widget_get_item (self->owner);
 }
 
 /**
@@ -316,23 +326,6 @@ gtk_list_item_set_child (GtkListItem *self,
   g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_ITEM]);
 }
 
-void
-gtk_list_item_set_item (GtkListItem *self,
-                        gpointer     item)
-{
-  g_return_if_fail (GTK_IS_LIST_ITEM (self));
-  g_return_if_fail (item == NULL || G_IS_OBJECT (item));
-
-  if (self->item == item)
-    return;
-
-  g_clear_object (&self->item);
-  if (item)
-    self->item = g_object_ref (item);
-
-  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_ITEM]);
-}
-
 /**
  * gtk_list_item_get_position:
  * @self: a #GtkListItem
@@ -345,23 +338,12 @@ gtk_list_item_set_item (GtkListItem *self,
 guint
 gtk_list_item_get_position (GtkListItem *self)
 {
-  g_return_val_if_fail (GTK_IS_LIST_ITEM (self), 0);
-
-  return self->position;
-}
-
-void
-gtk_list_item_set_position (GtkListItem *self,
-                            guint        position)
-{
-  g_return_if_fail (GTK_IS_LIST_ITEM (self));
-
-  if (self->position == position)
-    return;
+  g_return_val_if_fail (GTK_IS_LIST_ITEM (self), GTK_INVALID_LIST_POSITION);
 
-  self->position = position;
+  if (self->owner == NULL)
+    return GTK_INVALID_LIST_POSITION;
 
-  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_POSITION]);
+  return gtk_list_item_widget_get_position (self->owner);
 }
 
 /**
@@ -379,21 +361,10 @@ gtk_list_item_get_selected (GtkListItem *self)
 {
   g_return_val_if_fail (GTK_IS_LIST_ITEM (self), FALSE);
 
-  return self->selected;
-}
-
-void
-gtk_list_item_set_selected (GtkListItem *self,
-                            gboolean     selected)
-{
-  g_return_if_fail (GTK_IS_LIST_ITEM (self));
-
-  if (self->selected == selected)
-    return;
-
-  self->selected = selected;
+  if (self->owner == NULL)
+    return FALSE;
 
-  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_SELECTED]);
+  return gtk_list_item_widget_get_selected (self->owner);
 }
 
 /**
diff --git a/gtk/gtklistitemprivate.h b/gtk/gtklistitemprivate.h
index b84057f8382..d8f8833313c 100644
--- a/gtk/gtklistitemprivate.h
+++ b/gtk/gtklistitemprivate.h
@@ -32,23 +32,14 @@ struct _GtkListItem
 
   GtkListItemWidget *owner; /* has a reference */
 
-  GObject *item;
   GtkWidget *child;
-  guint position;
 
   guint activatable : 1;
   guint selectable : 1;
-  guint selected : 1;
 };
 
 GtkListItem *   gtk_list_item_new                               (void);
 
-void            gtk_list_item_set_item                          (GtkListItem            *self,
-                                                                 gpointer                item);
-void            gtk_list_item_set_position                      (GtkListItem            *self,
-                                                                 guint                   position);
-void            gtk_list_item_set_selected                      (GtkListItem            *self,
-                                                                 gboolean                selected);
 
 G_END_DECLS
 
diff --git a/gtk/gtklistitemwidget.c b/gtk/gtklistitemwidget.c
index b43eb761bfd..80750fcff58 100644
--- a/gtk/gtklistitemwidget.c
+++ b/gtk/gtklistitemwidget.c
@@ -29,6 +29,7 @@
 #include "gtklistitemfactoryprivate.h"
 #include "gtklistitemprivate.h"
 #include "gtkmain.h"
+#include "gtkselectionmodel.h"
 #include "gtkwidget.h"
 #include "gtkwidgetprivate.h"
 
@@ -37,6 +38,10 @@ struct _GtkListItemWidgetPrivate
 {
   GtkListItemFactory *factory;
   GtkListItem *list_item;
+
+  GObject *item;
+  guint position;
+  gboolean selected;
 };
 
 enum
@@ -54,13 +59,13 @@ gtk_list_item_widget_activate_signal (GtkListItemWidget *self)
 {
   GtkListItemWidgetPrivate *priv = gtk_list_item_widget_get_instance_private (self);
 
-  if (!priv->list_item->activatable)
+  if (priv->list_item && !priv->list_item->activatable)
     return;
 
   gtk_widget_activate_action (GTK_WIDGET (self),
                               "list.activate-item",
                               "u",
-                              priv->list_item->position);
+                              priv->position);
 }
 
 static gboolean
@@ -121,6 +126,7 @@ gtk_list_item_widget_dispose (GObject *object)
       gtk_list_item_factory_teardown (priv->factory, self);
       g_assert (priv->list_item == NULL);
     }
+  g_clear_object (&priv->item);
   g_clear_object (&priv->factory);
 
   G_OBJECT_CLASS (gtk_list_item_widget_parent_class)->dispose (object);
@@ -135,7 +141,7 @@ gtk_list_item_widget_select_action (GtkWidget  *widget,
   GtkListItemWidgetPrivate *priv = gtk_list_item_widget_get_instance_private (self);
   gboolean modify, extend;
 
-  if (!priv->list_item->selectable)
+  if (priv->list_item && !priv->list_item->selectable)
     return;
 
   g_variant_get (parameter, "(bb)", &modify, &extend);
@@ -143,7 +149,7 @@ gtk_list_item_widget_select_action (GtkWidget  *widget,
   gtk_widget_activate_action (GTK_WIDGET (self),
                               "list.select-item",
                               "(ubb)",
-                              priv->list_item->position, modify, extend);
+                              priv->position, modify, extend);
 }
 
 static void
@@ -229,13 +235,13 @@ gtk_list_item_widget_click_gesture_pressed (GtkGestureClick   *gesture,
   GtkListItemWidgetPrivate *priv = gtk_list_item_widget_get_instance_private (self);
   GtkWidget *widget = GTK_WIDGET (self);
 
-  if (!priv->list_item->selectable && !priv->list_item->activatable)
+  if (priv->list_item && !priv->list_item->selectable && !priv->list_item->activatable)
     {
       gtk_gesture_set_state (GTK_GESTURE (gesture), GTK_EVENT_SEQUENCE_DENIED);
       return;
     }
 
-  if (priv->list_item->selectable)
+  if (!priv->list_item || priv->list_item->selectable)
     {
       GdkModifierType state;
       GdkEvent *event;
@@ -250,17 +256,17 @@ gtk_list_item_widget_click_gesture_pressed (GtkGestureClick   *gesture,
       gtk_widget_activate_action (GTK_WIDGET (self),
                                   "list.select-item",
                                   "(ubb)",
-                                  priv->list_item->position, modify, extend);
+                                  priv->position, modify, extend);
     }
 
-  if (priv->list_item->activatable)
+  if (!priv->list_item || priv->list_item->activatable)
     {
       if (n_press == 2)
         {
           gtk_widget_activate_action (GTK_WIDGET (self),
                                       "list.activate-item",
                                       "u",
-                                      priv->list_item->position);
+                                      priv->position);
         }
     }
 
@@ -280,7 +286,7 @@ gtk_list_item_widget_enter_cb (GtkEventControllerFocus *controller,
   gtk_widget_activate_action (widget,
                               "list.scroll-to-item",
                               "u",
-                              priv->list_item->position);
+                              priv->position);
 }
 
 static void
@@ -381,6 +387,13 @@ gtk_list_item_widget_default_setup (GtkListItemWidget *self,
 
   if (list_item->child)
     gtk_list_item_widget_add_child (self, list_item->child);
+
+  if (priv->item)
+    g_object_notify (G_OBJECT (list_item), "item");
+  if (priv->position != GTK_INVALID_LIST_POSITION)
+    g_object_notify (G_OBJECT (list_item), "position");
+  if (priv->selected)
+    g_object_notify (G_OBJECT (list_item), "selected");
 }
 
 void
@@ -396,6 +409,13 @@ gtk_list_item_widget_default_teardown (GtkListItemWidget *self,
 
   if (list_item->child)
     gtk_list_item_widget_remove_child (self, list_item->child);
+
+  if (priv->item)
+    g_object_notify (G_OBJECT (list_item), "item");
+  if (priv->position != GTK_INVALID_LIST_POSITION)
+    g_object_notify (G_OBJECT (list_item), "position");
+  if (priv->selected)
+    g_object_notify (G_OBJECT (list_item), "selected");
 }
 
 void
@@ -405,9 +425,24 @@ gtk_list_item_widget_default_update (GtkListItemWidget *self,
                                      gpointer           item,
                                      gboolean           selected)
 {
-  gtk_list_item_set_item (list_item, item);
-  gtk_list_item_set_position (list_item, position);
-  gtk_list_item_set_selected (list_item, selected);
+  GtkListItemWidgetPrivate *priv = gtk_list_item_widget_get_instance_private (self);
+
+  /* FIXME: It's kinda evil to notify external objects from here... */
+  
+  if (g_set_object (&priv->item, item))
+    g_object_notify (G_OBJECT (list_item), "item");
+
+  if (priv->position != position)
+    {
+      priv->position = position;
+      g_object_notify (G_OBJECT (list_item), "position");
+    }
+
+  if (priv->selected != selected)
+    {
+      priv->selected = selected;
+      g_object_notify (G_OBJECT (list_item), "selected");
+    }
 }
 
 void
@@ -437,7 +472,7 @@ gtk_list_item_widget_get_position (GtkListItemWidget *self)
 {
   GtkListItemWidgetPrivate *priv = gtk_list_item_widget_get_instance_private (self);
 
-  return priv->list_item->position;
+  return priv->position;
 }
 
 gpointer
@@ -445,7 +480,7 @@ gtk_list_item_widget_get_item (GtkListItemWidget *self)
 {
   GtkListItemWidgetPrivate *priv = gtk_list_item_widget_get_instance_private (self);
 
-  return priv->list_item->item;
+  return priv->item;
 }
 
 gboolean
@@ -453,6 +488,6 @@ gtk_list_item_widget_get_selected (GtkListItemWidget *self)
 {
   GtkListItemWidgetPrivate *priv = gtk_list_item_widget_get_instance_private (self);
 
-  return priv->list_item->selected;
+  return priv->selected;
 }