static void mol_cancel_cb(Fl_Widget *w, void *v) { VMDApp *app = (VMDApp *)w->user_data(); MolBrowser *browser = (MolBrowser *)v; for (int i=0; i<browser->size(); i++) { if (browser->selected(i+1)) { int molid = app->molecule_id(i); app->molecule_cancel_io(molid); } } }