I tried many times, and now i have this declaration:
class ListModel : public QAbstractListModel
Qt Code: 
  1. {
  2.     Q_OBJECT
  3. public:
  4.     ListModel(QVector<QStringList> &my2darray, QObject *parent = 0)
  5.         : QAbstractListModel(parent), vector(my2darray){}
  6.  
  7.     int rowCount(const QModelIndex &parent = QModelIndex()) const;
  8.     QVariant data(const QModelIndex &index, int role) const;
  9.  
  10. private:
  11.     QVector<QStringList> &vector;
  12. };
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I would like to know, what can i return as QVariant? Only strings? i need to return a custom_widget i created (it consists of 4 labels). I tried this code:
QVariant ListModel::data(const QModelIndex &index, int role) const
Qt Code: 
  1. {
  2.      if (!index.isValid())
  3.          return QVariant();
  4.  
  5.      if (index.row() >= 20)
  6.          return QVariant();
  7.  
  8.      if (role == Qt::DisplayRole)
  9.      {
  10.          int a = index.row();
  11.          return Custom_Widget(vector[a][0], vector[a][1], vector[a][2], "");
  12.      }
  13.      else
  14.          return QVariant();
  15.  }
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But it didn't worked. How should I alter my code to get it working?