Re: forward declarations of gtkmm stuff

["Jonathon Jongsma" <jonathon quotidian org>]

On 1/2/08, David L <idht4n gmail com> wrote:
> On Jan 2, 2008 6:45 AM, Jonathon Jongsma <jonathon quotidian org> wrote:
>
> >
> > On 1/2/08, David L <idht4n gmail com> wrote:
> > > Sorry if this is a stupid question, but how can I forward declare
> > > gtkmm things so that gtkmm header files don't need to be
> > > included before defining a class that has gtkmm pointers?
> > >
> > > For example, I'd like to get rid of the two includes in this header
> file:
> > > // foo.h
> > > #include <gtkmm/window.h>
> > > #include <gtkmm/radioaction.h>
> >
> > namespace Gtk {
> > class Window;
> > class RadioAction;
> >
> > }
> >
> > > class foo {
> > >  public:
> > >   foo();
> > >  private:
> > >   Gtk::Window *myWindow;
> > >   Glib::RefPtr<Gtk::RadioAction> myRadioAction;
> > > };
> >
> > hope that helps
>
> Thanks!  That did fix the Gtk::Window problem... now I get this error:
>
> g++ -Wall -c -g  `pkg-config --cflags gtkmm-2.4` -o foo.o foo.cpp
> foo.h:13: error: 'Glib' has not been declared
> foo.h:13: error: ISO C++ forbids declaration of 'RefPtr' with no type
> foo.h:13: error: expected ';' before '<' token
> make: *** [foo.o ] Error 1
>
> But it works if I replace the original includes with:
> #include <glibmm/refptr.h>
>
> Is this the minimum set of header dependencies since
> the compiler needs to know that a RefPtr is a pointer?
> That header is 342 lines, which is a bit bigger than I'd
> like.  Any way to avoid refptr.h inclusion?

You can't avoid the refptr.h inclusion because you're using the RefPtr
class directly, not by pointer or reference (e.g. you have a
RefPtr<Foo> not a RefPtr<Foo>*).  So that's as good as you're going to
get.

-- 
jonner