Re: [PATCH gtk-3-16] GtkComboBox wrong menu_ypos

[Leslie Zhai <xiang zhai i-soft com cn>]

Implemented when active_item is not zero ;-)

When X11`s DisplayHeight minus GdkEventButton`s y_root is smaller than 
popup menu allocation`s height,
menu_ypos -= allocation.height;

But when active_item is bigger than zero, for example, pressed combo 
popup menu`s item 8,
menu_ypos += active_item * child_allocation.height;


diff --git a/gtk/gtkcombobox.c b/gtk/gtkcombobox.c
index ccda6ad..5f46920 100644
--- a/gtk/gtkcombobox.c
+++ b/gtk/gtkcombobox.c
@@ -159,6 +159,9 @@ struct _GtkComboBoxPrivate
   GdkDevice *grab_keyboard;

   gchar *tearoff_title;
+
+  guint y_root;
+  gint active_item;
 };

 /* While debugging this evil code, I have learned that
@@ -1125,6 +1128,9 @@ gtk_combo_box_init (GtkComboBox *combo_box)
   priv->text_column = -1;
   priv->text_renderer = NULL;
   priv->id_column = -1;
+
+  priv->y_root = 0;
+  priv->active_item = -1;
 }

 static void
@@ -1898,6 +1904,18 @@ gtk_combo_box_menu_position_below (GtkMenu *menu,
    *push_in = FALSE;
 }

+static GdkRectangle m_get_monitor_geo()
+{
+  GdkRectangle r;
+  GdkDisplay *display = gdk_display_get_default();
+  GdkScreen *screen = gdk_display_get_default_screen(display);
+  gint mon_id = gdk_screen_get_primary_monitor(screen);
+
+  gdk_screen_get_monitor_geometry(screen, mon_id, &r);
+
+  return r;
+}
+
 static void
 gtk_combo_box_menu_position_over (GtkMenu  *menu,
                                   gint     *x,
@@ -1956,6 +1974,14 @@ gtk_combo_box_menu_position_over (GtkMenu *menu,
       children = children->next;
     }

+  gtk_widget_get_allocation(GTK_WIDGET(menu), &allocation);
+  GdkRectangle display_rect = m_get_monitor_geo();
+  if (display_rect.height - combo_box->priv->y_root < allocation.height) {
+    menu_ypos -= allocation.height;
+    if (combo_box->priv->active_item != -1)
+      menu_ypos += combo_box->priv->active_item * child_allocation.height;
+  }
+
   if (gtk_widget_get_direction (widget) == GTK_TEXT_DIR_RTL)
     menu_xpos = menu_xpos + allocation.width - menu_width;

@@ -2244,6 +2270,7 @@ gtk_combo_box_menu_popup (GtkComboBox *combo_box,
     }

   /* FIXME handle nested menus better */
+  priv->active_item = active_item;
   gtk_menu_set_active (GTK_MENU (priv->popup_widget), active_item);

   if (priv->wrap_width == 0)
@@ -3237,6 +3264,8 @@ gtk_combo_box_menu_button_press (GtkWidget      
*widget,
           !gtk_widget_has_focus (priv->button))
         gtk_widget_grab_focus (priv->button);

+      priv->y_root = event->y_root;
+
       gtk_combo_box_menu_popup (combo_box, event->button, event->time);

       return TRUE;


On 2015年06月03日 09:52, Leslie Zhai wrote:
> Hi Gtk developers,
>
> I pay more attention to the gtk_combo_box_menu_position, the user 
> supplied function used to position the menu, when pressed the combobox 
> button 
> https://git.gnome.org/browse/gtk+/tree/gtk/gtkcombobox.c?h=gtk-3-16#n2268
>
> I argue that it ignore the relationship between DisplayHeight (use X11 
> style), GdkEventButton`s y_root and popup menu`s allocation height 
> https://twitter.com/xiangzhai/status/605902462189314048
>
> If DisplayHeight minus y_root is smaller than menu_alloc_height, the 
> menu_ypos should be minus menu_alloc_height, then my workaround patch 
> shown as below, not a monkey patch any more ;) 
> https://mail.gnome.org/archives/gtk-devel-list/2015-June/msg00000.html
>
>
> diff --git a/gtk/gtkcombobox.c b/gtk/gtkcombobox.c
> index ccda6ad..ce60473 100644
> --- a/gtk/gtkcombobox.c
> +++ b/gtk/gtkcombobox.c
> @@ -159,6 +159,7 @@ struct _GtkComboBoxPrivate
>    GdkDevice *grab_keyboard;
>
>    gchar *tearoff_title;
> +  guint y_root;
>  };
>
>  /* While debugging this evil code, I have learned that
> @@ -1125,6 +1126,8 @@ gtk_combo_box_init (GtkComboBox *combo_box)
>    priv->text_column = -1;
>    priv->text_renderer = NULL;
>    priv->id_column = -1;
> +
> +  priv->y_root = 0;
>  }
>
>  static void
> @@ -1898,6 +1901,18 @@ gtk_combo_box_menu_position_below (GtkMenu *menu,
>     *push_in = FALSE;
>  }
>
> +static GdkRectangle m_get_monitor_geo()
> +{
> +  GdkRectangle r;
> +  GdkDisplay *display = gdk_display_get_default();
> +  GdkScreen *screen = gdk_display_get_default_screen(display);
> +  gint mon_id = gdk_screen_get_primary_monitor(screen);
> +
> +  gdk_screen_get_monitor_geometry(screen, mon_id, &r);
> +
> +  return r;
> +}
> +
>  static void
>  gtk_combo_box_menu_position_over (GtkMenu  *menu,
>                                    gint     *x,
> @@ -1938,6 +1953,13 @@ gtk_combo_box_menu_position_over (GtkMenu *menu,
>        menu_ypos -= child_allocation.height / 2;
>      }
>
> +  gtk_widget_get_allocation(GTK_WIDGET(menu), &allocation);
> +  GdkRectangle display_rect = m_get_monitor_geo();
> +  if (display_rect.height - combo_box->priv->y_root < 
> allocation.height) {
> +    menu_ypos -= allocation.height;
> +  }
> +
>    children = GTK_MENU_SHELL 
> (combo_box->priv->popup_widget)->priv->children;
>    while (children)
>      {
> @@ -3237,6 +3261,7 @@ gtk_combo_box_menu_button_press (GtkWidget      
> *widget,
>            !gtk_widget_has_focus (priv->button))
>          gtk_widget_grab_focus (priv->button);
>
> +      priv->y_root = event->y_root;
>        gtk_combo_box_menu_popup (combo_box, event->button, event->time);
>
>        return TRUE;
>
>
> What about ***unimplented*** part? menu_ypos minus popup menu`s 
> allocation height is not enough when popup menu ***active*** item is, 
> for example, last one not the first, then menu_ypos should be plus the 
> height of active item to the first one, sorry for my poor English ;P

--
Regards,
Leslie Zhai