Qt 让Label显示图片并把图片居中

QPixmap image("./13.jpg");
 QPixmap fitpixmap=image.scaled(ui->label->size(), Qt::KeepAspectRatio, Qt::SmoothTransformation);
 ui->label->setPixmap(fitpixmap);
 ui->label->setAlignment(Qt::AlignCenter);
 ui->label->show();