void vc_widget::keyPressEvent(QKeyEvent *ev)
{
  if (ev->key() == Qt::Key_Up)
  {
    qDebug() << "press key up";
    return;
  }
  if (ev->key() == Qt::Key_Down)
  {
    qDebug() << "press key down";
    return;
  }
  if (ev->key() == Qt::Key_Left)
  {
    qDebug() << "press key left";
    return;
  }
  if (ev->key() == Qt::Key_Right)
  {
    qDebug() << "press key right";
    return;
  }
}
05-18 05:55