通过 GTK C 中的回调 function 传递变量

Question

I'm trying to print the value of the variable i on the console from my callback functon, but instead of printing 23 it keeps printing some address 11652528 etc...

I've been searching quite a lot on the net and according to an old GTK tutorial (where the actual G_CALLBACK Macro was GTK_SIGNAL_FUNC ) this should work.

Does anyone have an idea where the error is??

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

void f_window(GtkWidget* widget, gpointer data)
{
    g_print("%d\n",GPOINTER_TO_INT(data));
}
int main(int argc, char **argv)
{
    gint i=23;

    GtkWidget * MainWindow = NULL;

    gtk_init(&argc, &argv);

    MainWindow = gtk_window_new(GTK_WINDOW_TOPLEVEL);

    g_signal_connect(G_OBJECT(MainWindow),"delete-event",G_CALLBACK(f_window),GINT_TO_POINTER(i));

    gtk_widget_show_all(MainWindow);
    gtk_main();


    gtk_exit(EXIT_SUCCESS);
    return EXIT_SUCCESS;
}

thank you in advance!!!

Answer 1

The "delete-event" signal callback takes three arguments.

The function signature for f_window should be GtkWidget* widget, GdkEvent *event, gpointer data .

You are actually printing the value of event in your code.