Re : Problem with wxListbox and wxFileDialog

Hello world!!!
Ok, I've undestand how to fill a wxListBox with selected files.
But, why I can't fill my ListBox with this code?
Is there an another way to do this?

class MainWindow(wxFrame):
    def __init__(self,parent,id,title):
        wxFrame.__init__(self,parent,-4, title, size = ( 500,600),
        style=wxDEFAULT_FRAME_STYLE|wxNO_FULL_REPAINT_ON_RESIZE)

        barre_de_menu = wxMenuBar()
        file_menu01 = wxMenu()
        file_menu01.Append(ID_OPEN, "Open...\\tCtrl+O", "Cliquez sur Open pour ouvrir un fichier")
        barre_de_menu.Append(file_menu01, "&File")
        self.SetMenuBar(barre_de_menu)

        EVT_MENU(self, ID_OPEN, self.OnOpen)

    def OnOpen(self, event):
        """ Open a file"""
        dirname = 'c:\\media'
        dlg = wxFileDialog(self, "Choose a file :", dirname, "", "*.*", wxOPEN|wxMULTIPLE) #
        if dlg.ShowModal() == wxID_OK:
            self.filename=dlg.GetFilename()
            self.dirname=dlg.GetDirectory()
        event = Form1(frame, -1)
        for path in dlg.GetPaths():
            event.lb1.Append(path)

class Form1(wxPanel):
    def __init__(self, parent, id):
        self.panel = wxPanel.__init__(self, parent, id)

        List_Song = []
        self.lb1 = wxListBox(self, 60, wxPoint(300, 150), wxSize(80, 120),
                       List_Song, wxLB_SINGLE)

Thanks for all!!!