[gtksourceview: 2/2] CompletionContainer: another technique for the row height

[Sébastien Wilmet <swilmet src gnome org>]

commit 99073e747247f328cbc1e1a32e57638b4854c8a1
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Mon Jun 2 20:35:15 2014 +0200

    CompletionContainer: another technique for the row height
    
    The previous technique was buggy, it returned a too small row height.
    Now it should be fine.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=720823

 gtksourceview/gtksourcecompletioncontainer.c |   49 +++++++++++++------------
 1 files changed, 25 insertions(+), 24 deletions(-)
---
diff --git a/gtksourceview/gtksourcecompletioncontainer.c b/gtksourceview/gtksourcecompletioncontainer.c
index 8a81442..5de37aa 100644
--- a/gtksourceview/gtksourcecompletioncontainer.c
+++ b/gtksourceview/gtksourcecompletioncontainer.c
@@ -156,38 +156,39 @@ _gtk_source_completion_container_get_preferred_width (GtkWidget *widget,
 }
 
 static gint
-get_row_height (GtkSourceCompletionContainer *container)
+get_row_height (GtkSourceCompletionContainer *container,
+               gint                          tree_view_height)
 {
        GtkWidget *tree_view;
-       GList *columns;
-       GList *l;
-       gint max_row_height = 0;
-       gint vertical_separator = 0;
+       GtkTreeModel *model;
+       gint nb_rows;
+
+       /* For another possible implementation, see gtkentrycompletion.c in the
+        * GTK+ source code (the _gtk_entry_completion_resize_popup() function).
+        * It uses gtk_tree_view_column_cell_get_size() for retrieving the
+        * height, plus gtk_widget_style_get() to retrieve the
+        * "vertical-separator" height (note that the vertical separator must
+        * probably be counted one less time than the number or rows).
+        * But using that technique is buggy, it returns a smaller height (it's
+        * maybe a bug in GtkTreeView, or there are other missing parameters).
+        *
+        * Note that the following implementation doesn't take into account
+        * "vertical-separator". If there are some sizing bugs, it's maybe the
+        * source of the problem. (note that on my system the separator size was
+        * 0).
+        */
 
        tree_view = gtk_bin_get_child (GTK_BIN (container));
-       columns = gtk_tree_view_get_columns (GTK_TREE_VIEW (tree_view));
+       model = gtk_tree_view_get_model (GTK_TREE_VIEW (tree_view));
 
-       for (l = columns; l != NULL; l = l->next)
+       if (model == NULL)
        {
-               GtkTreeViewColumn *column = l->data;
-               gint row_height;
-
-               gtk_tree_view_column_cell_get_size (column, NULL, NULL, NULL, NULL, &row_height);
-
-               if (row_height > max_row_height)
-               {
-                       max_row_height = row_height;
-               }
+               return 0;
        }
 
-       gtk_widget_style_get (tree_view,
-                             "vertical-separator", &vertical_separator,
-                             NULL);
-
-       max_row_height += vertical_separator;
+       nb_rows = gtk_tree_model_iter_n_children (model, NULL);
 
-       g_list_free (columns);
-       return max_row_height;
+       return tree_view_height / nb_rows;
 }
 
 /* Return a height at a row boundary of the GtkTreeView. */
@@ -220,7 +221,7 @@ _gtk_source_completion_container_get_preferred_height (GtkWidget *widget,
 
        if (needs_vertical_scrollbar (nat_size.height))
        {
-               gint row_height = get_row_height (container);
+               gint row_height = get_row_height (container, nat_size.height);
                gint nb_rows_allowed = MAX_HEIGHT / row_height;
 
                ret_height = nb_rows_allowed * row_height + scrollbar_height;