GtkComboBoxEntry Vs GtkComboBox

["Peter E Dennis" <peter edwin dennis gmail com>]

Hi All,

I have the following code that I copied from the hello world part of
the GTK+ tutorial.  I used it to practice using GtkComboBoxEntry(s).

#include <gtk/gtk.h>

int main( int   argc,
          char *argv[] )
{
    /* GtkWidget is the storage type for widgets */
    GtkWidget *window;
    GtkWidget *cboVocSource;

    /* This is called in all GTK applications. Arguments are parsed
     * from the command line and are returned to the application. */
    gtk_init (&argc, &argv);

    /* create a new window */
    window = gtk_window_new (GTK_WINDOW_TOPLEVEL);

    /* Sets the border width of the window. */
    gtk_container_set_border_width (GTK_CONTAINER (window), 10);

    /* Creates a new combo box entry with the text Hello World */
    cboVocSource = gtk_combo_box_entry_new_text ();
    gtk_widget_set_name (cboVocSource, "cboVocSource");
    gtk_combo_box_append_text(cboVocSource, "Hello World");

    /* This packs the button into the window (a gtk container). */
    gtk_container_add (GTK_CONTAINER (window), cboVocSource);

    /* The final step is to display this newly created widget. */
    gtk_widget_show (cboVocSource);

    /* and the window */
    gtk_widget_show (window);

    /* All GTK applications must have a gtk_main(). Control ends here
     * and waits for an event to occur (like a key press or
     * mouse event). */
    gtk_main ();

    return 0;
}

I compile it with the following command:
$ gcc -Wall -g box.c -o box `pkg-config --cflags gtk+-2.0` `pkg-config
--libs gtk+-2.0`

And get this warning:
box.c: In function 'main':
box.c:23: warning: passing argument 1 of 'gtk_combo_box_append_text'
from incompatible pointer type

In the api it has the definition for gtk_combo_box_append_text as:
void gtk_combo_box_append_text        (GtkComboBox *combo_box,
                                                         const gchar *text);

So I wondered if I needed to cast my GtkComboBoxEntry to a GtkComboBox
but wasn't sure how to do this so I tried:

gtk_combo_box_append_text(GTK_COMBO(cboVocSource), "Hello World");

This however makes matters worse as I get the above warning still when
I compile it, but now when I run it I get:
$ ./box

(box:11338): GLib-GObject-WARNING **: invalid cast from
`GtkComboBoxEntry' to `GtkCombo'

Can someone please tell me what I'm doing wrong?

Many thanks,

Peter.