To speed-up QComboBox work with very big data set want to try to use QSqlQueryModel instead of QStandardItemModel. However text data in QComboBox I need to map to an ID, which is stored and accessible currently by itemData(rowIndex, Qt::UserRole). In QSqlQueryModel query there will be 2 columns: ID and Text; and QComboBox setModelColumn(1) is defined, i.e. Text.
How to correctly subclass or redefine QSqlQueryModel, if combobox->itemData(rowIndex, Qt::UserRole) have to contain ID? Who had implemented such things or know link to a source? If I define QVariant QSqlQueryModel::data(const QModelIndex & item, int role = Qt::DisplayRole) in a such way:
QVariant MySqlModel::data(const QModelIndex &index, int role) const
{
if(role == Qt::UserRole && index.column() == 1)
return QSqlQueryModel::data(this->index(index.row(), 0), Qt::DisplayRole);
return QSqlQueryModel::data(index, role);
}
will it work, i.e. whether combobox->itemData(rowIndex, Qt::UserRole) will contain ID in this case? Or need to investigate Qt sources?