[SOLVED] How to display QVector3D in one cell in QTableView via qAbstractTableModel's subclass

How to display QVector3D in one cell in QTableView via qAbstractTableModel's subclass

I'd like to display QVector3D in tableView, preferably like this: (x,y,z). I had subclassed the QAbstractTableModel class and implemented QAbstractTableModelSublass::data function:

QVariant data(const QModelIndex &index, int role= Qt::DisplayRole) const override
{
  ...
  if(role == Qt::DisplayRole)
  {  /* decide in which column and row to display the data*/
    QVector3D p(1.,2.,3.); return QVariant(p); 
  }
}

However, the target cell where the QVector3D should be displayed is empty. I'm quite positive that the correct QVariant instance is constructed, since I was able to print the value like this:

QVariant v = QVariant(p);
qDebug()<<v.value<QVector3D>();

What am I missing? How am I supposed to display the QVector3D in table in one cell?

Solution

The Qt::DisplayRole requires a QString in the variant, but you are providing a QVector3D. There is no conversion from QVector3D to QString in QVariant (see documentation).

You should either convert the Vector to a string representation yourself, or use a QStyledItemDelegate to override the displayText method for converting QVector3D to a string representations.

NB: Your debug output works, because there is a dedicated QDebug operator<<(QDebug dbg, const QVector3D &vector) for printing QVector3D in QDebug