Re: [Chicken-users] Define-external error

[William Ramsay]

This is basically the code I am using:

#>?
int g_signal_connect(void *, char *, void *, void *);
<#

(define-external (setColor ((pointer "GtkWidget") widget)
                  (c-pointer num))
  void
  (printf "num = ~A~%" num))

....
  (let
     ((cbut (gtk_color_button_new_with_color "#ffffff")))
....
     (g_signal_connect cbut "color-set" #$setColor ????? )

The question is what do I put where the ????? are?    The Gtk docs state 
that the "color-set" signal will return the widget that called the 
signal and "user data" as a gpointer.    No matter what I try I get a 
"not a pointer error" - including (make-locative x) which bombed when I 
tried to reference it with (locative-ref ..).    You must be able to do 
this, I just don't know how.    (I have a workaround, but I would still 
like to know how this is supposed to work).

Bill

felix winkelmann wrote:
> On 5/1/07, William Ramsay <address@hidden> wrote:
> > Hi,
> >
> > I don't know if this is a Ramsay, a Chicken, an easyFF, or a GTK error,
> > but I get the following when I use g_signal_connect, which is supposed
> > to call back to Scheme when a button is pressed.
> >
> > The command     (g_signal_connect button "color-set" #$setColor 1)
> >
> > Should call back to:   (define-external (setColor ((pointer
> > "GtkColorButton") widget)
> >
> >            (c-pointer data))
> >                                       void
> >                                       (printf "got data = ~A~%" data) )
> >
> > But it gives me a type error:
> >
> > Error: (location) bad argument type - locative can not refer to objects
> > of this type: #<procedure (setColor widget1371 data1372)>
>
> Does the callback definition appear textually after the g_signal_connect
> call? Can you send me the source file?
>
>
> cheers,
> felix