Passing additional arguments to gtk function

Question

I\'m trying to learn how to make GUIs using gtk+ 3.0. I want to pass a simple argument, an integer, to a callback function, so that when I press the button the value of the

Answer 1

int a = 42;
`gpointer ptr = GINT_TO_POINTER (a)`
//GUINT_TO_POINTER (a), GBOOLEAN_TO_POINTER (a), GSIZE_TO_POINTER (a)
reverse:

int a2 = GPOINTER_TO_INT (ptr);
//GPOINTER_TO_UINT (ptr), GPOINTER_TO_...

The above works perfectly fine to pass integer data thru g_signal_connect. Used as follows.

GtkWidget *Parison_ON_Buttons[10];

for (i=0; i < 8; i++)
{
    gpointer ONptr = GINT_TO_POINTER (i);
    g_signal_connect(GTK_SPIN_BUTTON(Parison_ON_Buttons[i]), "activate", G_CALLBACK 
    (Get_Parison_ON_Values),ONptr);
}

static gboolean Get_Parison_ON_Values (GtkSpinButton *button, gpointer data)
{
 int ONButtonNUmPressed = GPOINTER_TO_INT (data);
....
}