void CDropableMdiArea::dragEnterEvent(QDragEnterEvent *event) { QList<QMdiSubWindow *> list = subWindowList() ; for ( int i = 0 ; i < list.size() ; i ++ ) { QMdiSubWindow *p = list.at(i) ; if ( p->rect().contains(event->pos()-p->pos()) ) { event->ignore(); return ; } } event->accept(); }