- Qt 5.15
- Qt SQL
- C++ Classes
- QSqlRelationalDelegate
- Qt 5.15.18 Reference Documentation

# QSqlRelationalDelegate Class

The QSqlRelationalDelegate class provides a delegate that is used to display and edit data from a QSqlRelationalTableModel. More...

Header: | #include <QSqlRelationalDelegate>
qmake: | QT += sql
Inherits: | QItemDelegate

- List of all members, including inherited members

## Public Functions

| QSqlRelationalDelegate(QObject *parent = nullptr)
virtual | ~QSqlRelationalDelegate()

## Reimplemented Public Functions

virtual QWidget * | createEditor(QWidget *parent, const QStyleOptionViewItem &option, const QModelIndex &index) const override
virtual void | setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const override

## Detailed Description

Unlike the default delegate, QSqlRelationalDelegate provides a combobox for fields that are foreign keys into other tables. To use the class, simply call QAbstractItemView::setItemDelegate() on the view with an instance of QSqlRelationalDelegate:

         std::unique_ptr<QTableView> view{new QTableView};
         view->setModel(model);
         view->setItemDelegate(new QSqlRelationalDelegate(view.get()));

The Relational Table Model example (shown below) illustrates how to use QSqlRelationalDelegate in conjunction with QSqlRelationalTableModel to provide tables with foreign key support.

See also QSqlRelationalTableModel and Model/View Programming.

## Member Function Documentation

### QSqlRelationalDelegate::QSqlRelationalDelegate(QObject *parent = nullptr)

Constructs a QSqlRelationalDelegate object with the given parent.

### `[virtual]` QSqlRelationalDelegate::~QSqlRelationalDelegate()

Destroys the QSqlRelationalDelegate object and frees any allocated resources.

### `[override virtual]` QWidget *QSqlRelationalDelegate::createEditor(QWidget *parent, const QStyleOptionViewItem &option, const QModelIndex &index) const

Reimplements: QItemDelegate::createEditor(QWidget *parent, const QStyleOptionViewItem &option, const QModelIndex &index) const.

### `[override virtual]` void QSqlRelationalDelegate::setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const

Reimplements: QItemDelegate::setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const.