QMap排序方法运用实例

QVector<QPointF> ReadSonicPoint::sortSonicPoint(QVector<QPointF> befPointVector) //把x轴的值从小到大排序
{
  QVector<QPointF> modPointVector;
  QMap<double, double>sonicMap; //利用QMap自动排序
  for (int i = 0; i < befPointVector.size(); i++)
  {
    sonicMap.insert(befPointVector[i].x(), befPointVector[i].y());
  }
  QMap<double, double>::Iterator it = sonicMap.begin();
  while (it!=sonicMap.end())
  {
    QPointF sonicPoint;
    sonicPoint.setX(it.key());
    sonicPoint.setY(it.value());
    modPointVector.append(sonicPoint);
        i++;
  }
  return modPointVector;
}