Re: How to use a combo box with a cell renderer

[Martyn Russell <martyn russell bt com>]

On Wed, 2004-12-22 at 06:40 -0500, Hudson Lee wrote:
> Please reply to me (spam nilmail com) directly, I'm not sure if I'm subscribed.
>
> Okay so I'm using gtk 2.4 what am I doing wrong the following code (simple test
> program) doesn't show me any text when I click the combo menu.
>
> //compile with...
> //gcc combo_test.c -o ct `pkg-config --cflags --libs gtk+-2.0` && ./ct
> #include <gtk/gtk.h>
>
> int main(int argc, char *argv[]){
>
>   GtkWidget *window, *combo;
>   GtkListStore *store;
>   GtkTreeIter iter;
>   GtkCellRenderer *renderer;
>
>   gtk_init (&argc, &argv);
>   window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
>   
>   store = gtk_list_store_new(1, G_TYPE_STRING);
>   gtk_list_store_append(store, &iter);
>   gtk_list_store_set(store, &iter, 0, "Why can't I see this text at all", -1);
>   combo = gtk_combo_box_new_with_model(GTK_TREE_MODEL(store));
>   renderer = gtk_cell_renderer_text_new();
>   gtk_cell_layout_pack_start(GTK_CELL_LAYOUT(combo), renderer, TRUE);
>
>   gtk_container_add(GTK_CONTAINER(window), combo);
>   gtk_widget_show_all(window);
>   gtk_main();
>   return 0;
> }

Hi,

At first I thought that it was because you hadn't associated an
attribute with the renderer (see gtk_cell_layout_set_attributes() for
more on this), but then when I add that function or use of
gtk_cell_layout_add_attribute() it Seg Faults? I would expect this to
work!

If you uncomment the #define it uses the simpler method and works
perfectly as expected.

Matthias, any clues here?

[...]
#include <gtk/gtk.h>

/*#define WORKS*/

int main(int argc, char *argv[]){

  GtkWidget *window, *combo;
  GtkListStore *store;
  GtkTreeIter iter;
  GtkCellRenderer *renderer;
  GtkCellLayout *layout;

  gtk_init (&argc, &argv);
  window = gtk_window_new (GTK_WINDOW_TOPLEVEL);

  store = gtk_list_store_new(1, G_TYPE_STRING);
  gtk_list_store_append(store, &iter);
  gtk_list_store_set(store, &iter, 0, "Why can't I see this text at
all", -1);
#ifdef WORKS
  combo = gtk_combo_box_new_text();
  gtk_combo_box_set_model(GTK_COMBO_BOX(combo), GTK_TREE_MODEL(store));
#else
  combo = gtk_combo_box_new_with_model(GTK_TREE_MODEL(store));
  renderer = gtk_cell_renderer_text_new();
  layout = GTK_CELL_LAYOUT(combo);
  gtk_cell_layout_clear (layout);
  /* the following line crashes: */
  /* gtk_cell_layout_set_attributes (layout, renderer, "text", 0, NULL);
*/
  gtk_cell_layout_pack_start(layout, renderer, TRUE);
#endif
  gtk_container_add(GTK_CONTAINER(window), combo);
  gtk_widget_show_all(window);
  gtk_main();
  return 0;
}
[...]

-- 
Regards,
Martyn