Re: How to use GtkTreeSortable.

[Olexiy Avramchenko <ath beast stu cn ua>]

Johan wrote:
> On Tue, 22 Oct 2002 10:08:34 +0300
> Olexiy Avramchenko <ath beast stu cn ua> wrote:
>
> > As I think there's a file size column in your tree model (of type G_TYPE_INT
> > or so). All you need is to call gtk_tree_view_column_set_sort_column_id()
> > on that column.
> >
> > enum {
> > <skipped>
> >   COLUMN_FILE_SIZE,
> > <skipped>
> > };
> >
> > <skipped>
> > {
> > GtkTreeViewColumn *column;
> > <skipped>
> >     column = gtk_tree_view_column_new_with_attributes(...);
> >     gtk_tree_view_column_set_sort_column_id (column, COLUMN_FILE_SIZE)
> > <skipped>
> > }
> >
> > Olexiy
> >   
>
> Hello.
> I have a file size column of type G_TYPE_STRING and displays the
> file size like 3.3 MB, 454 Kb, 544 B etc.
>
> I am currently using gtk_tree_view_set_sort_column_id, but the sort
> function sorts the size in alphabetic order, which is incorect
> for this column.
>
> I need to build my own method to sort this column. Do you know
> how gtk_tree_sortable_set_sort_func() works?
I've attached a small example. You also can take a look at
"gtktreedatalist.c" -> gtk_tree_data_list_compare_func().

Hope this helps.

Olexiy



gint special_cmp_function(
                                GtkTreeModel *model,
                                GtkTreeIter  *a,
                                GtkTreeIter  *b,
                                gpointer      data
)
{
gint            column = (gint)data;
GType           type = gtk_tree_model_get_column_type(model, column);
GValue          va = {0, };
GValue          vb = {0, };
gchar           *sa, *sb;
gdouble         ba, bb;

        /* getting string values from model */
        gtk_tree_model_get_value(model, a, column, &va);
        gtk_tree_model_get_value(model, b, column, &vb);

        /* if values are not of type G_STRING - abort,
           return value means '==', so nothing special will be performed */
        g_return_val_if_fail(G_TYPE_FUNDAMENTAL(type) != G_TYPE_STRING, 0);

        /* getting strings from values */
        sa = (gchar*)g_value_get_string(&va);
        sb = (gchar*)g_value_get_string(&vb);

        /* getting byte values from strings, only "<float>MB" "<float>KB" and
           "<float>" format handled */
        if (!sa) {
                ba = 0;
        }
        else {
                if (sscanf(sa, "%fMB", &ba) == 1)
                        ba *= 1024*1024;
                else
                if (sscanf(sa, "%fKB", &ba) == 1)
                        ba *= 1024;
                else    sscanf(sa, "%f", &ba);
        }
        if (!sb) {
                bb = 0;
        }
        else {
                if (sscanf(sb, "%fMB", &bb) == 1)
                        bb *= 1024*1024;
                else
                if (sscanf(sb, "%fKB", &bb) == 1)
                        bb *= 1024;
                else    sscanf(sa, "%f", &bb);

        }

        /* freeing values */
        g_value_unset(&va);
        g_value_unset(&vb);

        if (ba < bb)
                return -1;
        else    if (ba > bb)
                        return 1;

        return 0;
}