this->setWindowFlags(Qt::MSWindowsFixedSizeDialogHint | Qt::WindowTitleHint | Qt::Dialog | Qt::WindowMinimizeButtonHint | Qt::CustomizeWindowHint);
C++ (Qt)setWindowFlags(((windowFlags() | Qt::CustomizeWindowHint)& ~Qt::WindowCloseButtonHint));show();
C++ (Qt)HMENU menu = ::GetSystemMenu(this->winId(), FALSE); ::DeleteMenu(menu, SC_CLOSE, MF_BYCOMMAND); ::EnableMenuItem(menu, SC_CLOSE, MF_BYCOMMAND | MF_GRAYED);