Gtkmm Save Dialog problem

[TimAnderson]

I'm trying to save a Pixbuf to a file with a FileChooserDialog in SAVE mode but am running into a problem that I can't figure out.

Here's my code:

void GUI::saveDialog ()
{
    FileChooserDialog dialog ("Save...", FILE_CHOOSER_ACTION_SAVE);

    dialog.set_transient_for (*this);
    dialog.set_do_overwrite_confirmation (true);
    dialog.set_create_folders (true);
    dialog.add_button (GTK_STOCK_CANCEL, RESPONSE_CANCEL);
    dialog.add_button (GTK_STOCK_SAVE, RESPONSE_OK);

    vector<PixbufFormat> formats = Pixbuf::get_formats ();

    for (unsigned int i=0 ; i<formats.size() ; i++)
    {
        if (formats[i].is_writable())
        {
            FileFilter filter;

            filter.set_name (formats[i].get_name());

            vector<string> patterns = formats[i].get_extensions();
            for (unsigned int j=0 ; j<patterns.size() ; j++)
            {
                filter.add_pattern (patterns[j]);
            }

            dialog.add_filter (filter);
        }
    }

    dialog.set_current_folder (folder);

    dialog.set_current_name (getSaveFilename ());

    if (dialog.run () == RESPONSE_OK)
    {
        string filename = dialog.get_filename ();

        FileFilter* filter = dialog.get_filter ();
        const gchar* filterName = gtk_file_filter_get_name (filter->gobj());

        if (filename.find_last_of ('.') == string::npos)
        {
            filename += ".";
            filename += filterName;
        }

        save (filename, filterName);
    }
}

When I try to get the filter name from the dialog, I get the following messages:

(CompareProfiles:12142): glibmm-WARNING **: Glib::wrap_create_new_wrapper: Attempted to create a 2nd C++ wrapper for a C instance whose C++ wrapper has been deleted.

(CompareProfiles:12142): glibmm-WARNING **: Failed to wrap object of type 'gtkmm__GtkFileFilter'. Hint: this error is commonly caused by failing to call a library init() function.

I get the same messages if I use gtkmm's dialog.get_filter()->get_name(). I tried using the gtk+ to see if I could get it to work that way but came up with the same messages.

Any ideas on what I am doing wrong? Any help is greatly appreciated!