这个可以吧:
QMessageBox msgBox;
QPushButton *connectButton = msgBox.addButton(tr("Connect"), QMessageBox::ActionRole);
QPushButton *abortButton = msgBox.addButton(QMessageBox::Abort);
msgBox.exec();
if (msgBox.clickedButton() == connectButton) {
// connect
} else if (msgBox.clickedButton() == abortButton) {
// abort
}