Problem with Data Passed to Call Back Function



Hello,


In the program below I am creating 3 buttons in a
horizontal box.  The buttons get created and labeled
properly as:

Button 1
Button 2
Button 3

When I click on any of the buttons though,
the data sent to the callback function should
be the label of the button pressed.
Instead it all shows up as:

Button 3

The button labels are stored in an array of character
pointers which appears to work find in the for loop.
Once out, if I print out the contents of the array
of character pointers they are all:

Button 3

I am guessing that I am missing some simple
problem but have been unable to find it on
my own.
Any help would be appreciated.

Thanks

Chris


#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <gtk/gtk.h>

static void button_cb (GtkWidget *widget, gpointer data)
   {
       g_print ("Hello - %s was pressed\n", (gchar *) data);
   }

static void delete_event_cb(GtkWidget *widget, GdkEvent *event, gpointer data)
   {
       g_print ("A delete event has occurred\n");
       gtk_main_quit();
   }

int main( int   argc,
         char *argv[] )
   {
       GtkWidget *window;
       GtkWidget *button;
       GtkWidget *box1;
       gchar *newstr[3];
       gchar tmpstr[12];
       gint i;

       gtk_init (&argc, &argv);
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
       gtk_window_set_title (GTK_WINDOW (window), "Test Program");
       gtk_container_set_border_width (GTK_CONTAINER (window), 50);
g_signal_connect (G_OBJECT (window), "delete_event", G_CALLBACK (delete_event_cb), NULL); box1 = gtk_hbox_new (TRUE, 20);
       gtk_container_add (GTK_CONTAINER (window), box1);

for (i=1; i<=3; i=i+1)
         {
           sprintf(tmpstr,"%s%d","Button ",i);
printf("The value of tmpstr = %s\n",tmpstr); /* Prints Button 1, Button 2, Button 3*/
           newstr[i-1] = tmpstr;
printf("The current label is %s\n",newstr[i-1]); /* Prints Button 1, Button 2, Button 3*/ button = gtk_button_new_with_label (newstr[i-1]); g_signal_connect (G_OBJECT (button), "clicked", G_CALLBACK (button_cb), (gpointer) newstr[i-1]);
           gtk_box_pack_start (GTK_BOX(box1), button, TRUE, TRUE, 0);
           gtk_widget_show (button);
printf("The current label is %s\n",newstr[i-1]); /* Prints Button 1, Button 2, Button 3*/
         }

printf("The value of element 1 is %s\n",newstr[0]); /* Prints Button 3*/ printf("The value of element 2 is %s\n",newstr[1]); /* Prints Button 3*/ printf("The value of element 3 is %s\n",newstr[2]); /* Prints Button 3*/

       gtk_widget_show (box1);
       gtk_widget_show (window);
gtk_main (); return 0;
   }






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