g_signal_connect ((gpointer) tlbGoToTime, "clicked",
G_CALLBACK (on_button_go_to_time_clicked),
NULL);
g_signal_connect ((gpointer) tlbShowTimeFrame, "clicked",
G_CALLBACK (on_button_show_time_frame_clicked),
NULL);
g_signal_connect ((gpointer) tlbGoToTime, "clicked",
G_CALLBACK (on_button_go_to_time_clicked),
NULL);
g_signal_connect ((gpointer) tlbShowTimeFrame, "clicked",
G_CALLBACK (on_button_show_time_frame_clicked),
NULL);