[gtk+/gtk-2-24] filechooserbutton: Don't show the (None) item when the combo box is popped up

[Federico Mena Quintero <federico src gnome org>]

commit 6dc11c26a880753c95bc420a2bec7ada270adbbb
Author: Federico Mena Quintero <federico gnome org>
Date:   Thu Mar 7 17:20:16 2013 -0600

    filechooserbutton: Don't show the (None) item when the combo box is popped up
    
    This is surprisingly tricky, since the (None) item *has* to be a visible item while
    the combo box is *not* popped up, so that it can show its contents.  But the item
    has to be *not* visible when the combo box is popped up.
    
    Also, update the whole button's selection, not just the underlying dialog's, when
    the combo box changes its selection - based on a patch by Paul Davis in
    https://bugzilla.gnome.org/show_bug.cgi?id=691040#c20
    
    Signed-off-by: Federico Mena Quintero <federico gnome org>

 gtk/gtkfilechooserbutton.c |  120 +++++++++++++++++++++++++++++++++++++-------
 1 files changed, 101 insertions(+), 19 deletions(-)
---
diff --git a/gtk/gtkfilechooserbutton.c b/gtk/gtkfilechooserbutton.c
index e2af20e..f998855 100644
--- a/gtk/gtkfilechooserbutton.c
+++ b/gtk/gtkfilechooserbutton.c
@@ -290,6 +290,9 @@ static void     fs_bookmarks_changed_cb          (GtkFileSystem  *fs,
 
 static void     combo_box_changed_cb             (GtkComboBox    *combo_box,
                                                  gpointer        user_data);
+static void     combo_box_notify_popup_shown_cb  (GObject        *object,
+                                                 GParamSpec     *pspec,
+                                                 gpointer        user_data);
 
 static void     button_clicked_cb                (GtkButton      *real_button,
                                                  gpointer        user_data);
@@ -496,9 +499,12 @@ gtk_file_chooser_button_init (GtkFileChooserButton *button)
                                        G_TYPE_POINTER   /* CANCELLABLE_COLUMN */));
 
   priv->combo_box = gtk_combo_box_new ();
-  priv->combo_box_changed_id =
-    g_signal_connect (priv->combo_box, "changed",
-                     G_CALLBACK (combo_box_changed_cb), button);
+  priv->combo_box_changed_id = g_signal_connect (priv->combo_box, "changed",
+                                                G_CALLBACK (combo_box_changed_cb), button);
+
+  g_signal_connect (priv->combo_box, "notify::popup-shown",
+                   G_CALLBACK (combo_box_notify_popup_shown_cb), button);
+
   gtk_container_add (GTK_CONTAINER (button), priv->combo_box);
 
   priv->icon_cell = gtk_cell_renderer_pixbuf_new ();
@@ -2318,6 +2324,34 @@ filter_model_visible_func (GtkTreeModel *model,
          }
       }
       break;
+    case ROW_TYPE_EMPTY_SELECTION:
+      {
+       gboolean popup_shown;
+
+       g_object_get (priv->combo_box,
+                     "popup-shown", &popup_shown,
+                     NULL);
+
+       if (popup_shown)
+         retval = FALSE;
+       else
+         {
+           GFile *selected;
+
+           /* When the combo box is not popped up... */
+
+           selected = get_selected_file (button);
+           if (selected)
+             retval = FALSE; /* ... nonempty selection means the ROW_TYPE_EMPTY_SELECTION is *not* 
visible... */
+           else
+             retval = TRUE;  /* ... and empty selection means the ROW_TYPE_EMPTY_SELECTION *is* visible */
+
+           if (selected)
+             g_object_unref (selected);
+         }
+
+       break;
+      }
     default:
       retval = TRUE;
       break;
@@ -2359,7 +2393,22 @@ combo_box_row_separator_func (GtkTreeModel *model,
   return (type == ROW_TYPE_BOOKMARK_SEPARATOR ||
          type == ROW_TYPE_CURRENT_FOLDER_SEPARATOR ||
          type == ROW_TYPE_OTHER_SEPARATOR);
-}                        
+}
+
+static void
+select_combo_box_row_no_notify (GtkFileChooserButton *button, int pos)
+{
+  GtkFileChooserButtonPrivate *priv = button->priv;
+  GtkTreeIter iter, filter_iter;
+  
+  gtk_tree_model_iter_nth_child (priv->model, &iter, NULL, pos);
+  gtk_tree_model_filter_convert_child_iter_to_iter (GTK_TREE_MODEL_FILTER (priv->filter_model),
+                                                   &filter_iter, &iter);
+
+  g_signal_handler_block (priv->combo_box, priv->combo_box_changed_id);
+  gtk_combo_box_set_active_iter (GTK_COMBO_BOX (priv->combo_box), &filter_iter);
+  g_signal_handler_unblock (priv->combo_box, priv->combo_box_changed_id);
+}
 
 static void
 update_combo_box (GtkFileChooserButton *button)
@@ -2427,14 +2476,11 @@ update_combo_box (GtkFileChooserButton *button)
   if (!row_found)
     {
       gint pos;
-      GtkTreeIter filter_iter;
 
       /* If it hasn't been found already, update & select the current-folder row. */
       if (file)
        {
          model_update_current_folder (button, file);
-         gtk_tree_model_filter_refilter (GTK_TREE_MODEL_FILTER (priv->filter_model));
-
          pos = model_get_type_position (button, ROW_TYPE_CURRENT_FOLDER);
        }
       else
@@ -2444,13 +2490,9 @@ update_combo_box (GtkFileChooserButton *button)
          pos = model_get_type_position (button, ROW_TYPE_EMPTY_SELECTION);
        }
 
-      gtk_tree_model_iter_nth_child (priv->model, &iter, NULL, pos);
-      gtk_tree_model_filter_convert_child_iter_to_iter (GTK_TREE_MODEL_FILTER (priv->filter_model),
-                                                       &filter_iter, &iter);
+      gtk_tree_model_filter_refilter (GTK_TREE_MODEL_FILTER (priv->filter_model));
 
-      g_signal_handler_block (priv->combo_box, priv->combo_box_changed_id);
-      gtk_combo_box_set_active_iter (GTK_COMBO_BOX (priv->combo_box), &filter_iter);
-      g_signal_handler_unblock (priv->combo_box, priv->combo_box_changed_id);
+      select_combo_box_row_no_notify (button, pos);
     }
 
   if (file)
@@ -2738,21 +2780,17 @@ combo_box_changed_cb (GtkComboBox *combo_box,
        case ROW_TYPE_SHORTCUT:
        case ROW_TYPE_BOOKMARK:
        case ROW_TYPE_CURRENT_FOLDER:
-         gtk_file_chooser_unselect_all (GTK_FILE_CHOOSER (priv->dialog));
          if (data)
-           gtk_file_chooser_set_current_folder_file (GTK_FILE_CHOOSER (priv->dialog),
-                                                     data, NULL);
+           gtk_file_chooser_button_set_current_folder (GTK_FILE_CHOOSER (button), data, NULL);
          break;
        case ROW_TYPE_VOLUME:
          {
            GFile *base_file;
 
-           gtk_file_chooser_unselect_all (GTK_FILE_CHOOSER (priv->dialog));
            base_file = _gtk_file_system_volume_get_root (data);
            if (base_file)
              {
-               gtk_file_chooser_set_current_folder_file (GTK_FILE_CHOOSER (priv->dialog),
-                                                         base_file, NULL);
+               gtk_file_chooser_button_set_current_folder (GTK_FILE_CHOOSER (button), base_file, NULL);
                g_object_unref (base_file);
              }
          }
@@ -2766,6 +2804,50 @@ combo_box_changed_cb (GtkComboBox *combo_box,
     }
 }
 
+/* Calback for the "notify::popup-shown" signal on the combo box.
+ * When the combo is popped up, we don't want the ROW_TYPE_EMPTY_SELECTION to be visible
+ * at all; otherwise we would be showing a "(None)" item in the combo box's popup.
+ *
+ * However, when the combo box is *not* popped up, we want the empty-selection row
+ * to be visible depending on the selection.
+ *
+ * Since all that is done through the filter_model_visible_func(), this means
+ * that we need to refilter the model when the combo box pops up - hence the
+ * present signal handler.
+ */
+static void
+combo_box_notify_popup_shown_cb (GObject    *object,
+                                GParamSpec *pspec,
+                                gpointer    user_data)
+{
+  GtkFileChooserButton *button = GTK_FILE_CHOOSER_BUTTON (user_data);
+  GtkFileChooserButtonPrivate *priv = button->priv;
+  gboolean popup_shown;
+
+  g_object_get (priv->combo_box,
+               "popup-shown", &popup_shown,
+               NULL);
+
+  /* Indicate that the ROW_TYPE_EMPTY_SELECTION will change visibility... */
+  gtk_tree_model_filter_refilter (GTK_TREE_MODEL_FILTER (priv->filter_model));
+
+  /* If the combo box popup got dismissed, go back to showing the ROW_TYPE_EMPTY_SELECTION if needed */
+  if (!popup_shown)
+    {
+      GFile *selected = get_selected_file (button);
+
+      if (!selected)
+       {
+         int pos;
+
+         pos = model_get_type_position (button, ROW_TYPE_EMPTY_SELECTION);
+         select_combo_box_row_no_notify (button, pos);
+       }
+      else
+       g_object_unref (selected);
+    }
+}
+
 /* Button */
 static void
 button_clicked_cb (GtkButton *real_button,