get_window() returns NULL

[Andrea Spadaccini <a spadaccini catania linux it>]

Hi everyone,
I've got a problem with get_window().. gdb backtrace shows me that a
segfault is caused by this function returning NULL from inside a member
of my SubnetRenderer class, which is derived from Gtk::Drawable. here's
the function that generates the problem:

void SubnetRenderer::setStatus(int s) {
    Gdk::Cursor ar(Gdk::ARROW);
    Gdk::Cursor ch(Gdk::CROSSHAIR);

    // Non funge, non capisco perché..
    Glib::RefPtr<Gdk::Window> w = get_window();
    std::cout << "Sono qui! :)\n";
    Gdk::Color c("black");
    //gc->set_foreground(mainColor);
    if(w == NULL)
        std::cout << "E' NULL!!!\n";
    w->set_cursor(ar);
    
    switch(s) {
        case DEFAULT:
            sb_text = "Selezionare un oggetto per informazioni";
            break;
        case ADD_HOST:
            cleanSelections();
            sb_text = "Cliccare su un punto della mappa per aggiungere
un host."; break;
        case ADD_ROUTER:
            cleanSelections();
            //get_window()->set_cursor(ch);
            sb_text = "Cliccare su un punto della mappa per aggiungere
un router."; break;
        case SOMETHING_IS_SELECTED:
            sb_text = selected->getInfo();
            break;
        default:
            sb_text = "Questo stato è impossibile. Come direbbe
Nunnari: \"Sei un PIIIIRLA\""; break;
    }
    status = s;
}

and here's the backtrace

[...]

(gdb) run
Starting program: /home/andrea/Uni/Reti di Calcolatori/simulatore_reti/
Sim Sono qui! :)
E' NULL!!!

Program received signal SIGSEGV, Segmentation fault.
Gdk::Window::set_cursor(Gdk::Cursor const&) (this=0x0,
cursor= 0xbffff110) at window.h:719
719     window.h: No such file or directory.
        in window.h
(gdb) bt
#0  Gdk::Window::set_cursor(Gdk::Cursor const&) (this=0x0,
cursor= 0xbffff110) at window.h:719
#1  0x08094f6d in SubnetRenderer::setStatus(int) (this=0xbffff4a0, s=0)
    at SubnetRenderer.cpp:178
#2  0x08093f5a in SubnetRenderer (this=0xbffff4a0, xsize=700, ysize=600,
    dwb=0x0, ldwb=0x0) at SubnetRenderer.cpp:40
#3  0x08099ee6 in TestWindow (this=0xbffff490) at TestWindow.cpp:25
#4  0x080a1705 in main (argc=1, argv=0xbffff854) at Tester.cpp:8
#5  0x4093e469 in __libc_start_main () from /lib/libc.so.6
(gdb)


PLEASE HELP ME!! I'm going MAD!!
thanks in advance!!


-- 
[ Andrea Spadaccini - a.k.a. Lupino/Lupin85 - Catania - ICQ#: 91528290 ]
[ GPG ID: 5D41ABF0 - key @ pgp.mit.edu - Slackware 10.1 w/Linux 2.4.22 ]
[ Linux User # 313388 - MAIL: a.spadaccini(at)catania(dot)linux(dot)it ]
[ Penguins like this song: <Sconosciuto> - Coldplay - 10 - Everythings ]

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