QModelRoleData Class Reference

\inmodule QtCore More...

#include <qabstractitemmodel.h>

Collaboration diagram for QModelRoleData:

Public Member Functions
	QModelRoleData (int role) noexcept
	Constructs a QModelRoleData object for the given role.
constexpr int	role () const noexcept
	Returns the role held by this object.
constexpr QVariant &	data () noexcept
	Returns the data held by this object as a modifiable reference.
constexpr const QVariant &	data () const noexcept
	Returns the data held by this object.
template<typename T >
constexpr void	setData (T &&value) noexcept(noexcept(m_data.setValue(std::forward< T >(value))))
	Sets the data held by this object to value.
void	clearData () noexcept
	Clears the data held by this object.

Detailed Description

\inmodule QtCore

Since

6.0

The QModelRoleData class holds a role and the data associated to that role.

QModelRoleData objects store an item role (which is a value from the Qt::ItemDataRole enumeration, or an arbitrary integer for a custom role) as well as the data associated with that role.

A QModelRoleData object is typically created by views or delegates, setting which role they want to fetch the data for. The object is then passed to models (see QAbstractItemModel::multiData()), which populate the data corresponding to the role stored. Finally, the view visualizes the data retrieved from the model.

See also

{Model/View Programming}, QModelRoleDataSpan

Definition at line 17 of file qabstractitemmodel.h.

Constructor & Destructor Documentation

QModelRoleData()

QModelRoleData::QModelRoleData ( int  role )

inlineexplicitnoexcept

Constructs a QModelRoleData object for the given role.

See also

Qt::ItemDataRole

Definition at line 23 of file qabstractitemmodel.h.

Member Function Documentation

clearData()

void QModelRoleData::clearData ( )

inlinenoexcept

Clears the data held by this object.

Note that the role is unchanged; only the data is cleared.

See also

data()

Definition at line 35 of file qabstractitemmodel.h.

References m_data.

data() [1/2]

const QVariant & QModelRoleData::data ( ) const

inlineconstexprnoexcept

Returns the data held by this object.

See also

setData()

Definition at line 29 of file qabstractitemmodel.h.

References m_data.

data() [2/2]

QVariant & QModelRoleData::data ( )

inlineconstexprnoexcept

Returns the data held by this object as a modifiable reference.

See also

setData()

Definition at line 28 of file qabstractitemmodel.h.

References m_data.

role()

int QModelRoleData::role ( ) const

inlineconstexprnoexcept

Returns the role held by this object.

See also

Qt::ItemDataRole

Definition at line 27 of file qabstractitemmodel.h.

setData()

template<typename T >

template< typename T > void QModelRoleData::setData ( T &&  value )

inlineconstexprnoexcept

Sets the data held by this object to value.

value must be of a datatype which can be stored in a QVariant.

See also

data(), clearData(), Q_DECLARE_METATYPE

Definition at line 32 of file qabstractitemmodel.h.

References m_data.

---

The documentation for this class was generated from the following files:

• qtbase/src/corelib/itemmodels/qabstractitemmodel.h
• qtbase/src/corelib/itemmodels/qabstractitemmodel.cpp