GTK Buttons

GTK Buttons (gtk_button, defined in gtkbutton.h) are used to create push-buttons. We can attach a callback to a 'pressed' signal, as well as to a few other signals.

/* create a new button. */
GtkWidget* button = gtk_button_new_with_label("Hello World");

/* set a callback for the 'clicked' signal of the button.    */
/* the given gpointer will be passed as the 'data' parameter */
/* to the callback.                                          */
gtk_signal_connect(GTK_OBJECT(search_button), "clicked",
                   GTK_SIGNAL_FUNC(on_button_clicked),
                   (gpointer)"tough");

And the callback function itself:

void
on_button_clicked(GtkButton* button, gpointer data)
{
    /* cast the data back to a char*  */
    char* txt = (char*)data;
    printf("on_button_clicked - '%s'\n", txt);
    fflush(stdout);
}