+ // std::cout << "update"<<std::endl;
+ // std::cout << "OW = "<< mBox->bbGetWindow() << std::endl;
+ // std::cout << "CW = "<< mBox->bbGetContainingWindow() << std::endl;
+ // std::cout << "Sh = "<< mBox->bbIsShown() << std::endl;
+
+ // mBox->bbIsShown() is necessary to be sure that the wxWindow is already
+ // created and displayed.
+ // Else when slice != 0 we get an X Window System error with wxGTK
+ if ((backImageData!=NULL)&&(mBox->bbIsShown()))