QPersistentModelIndex Class

The QPersistentModelIndex class is used to locate data in a data model. 更多...

头：	#include <QPersistentModelIndex>
qmake:	QT += core

公共函数

	QPersistentModelIndex (QPersistentModelIndex && other )
	QPersistentModelIndex (const QPersistentModelIndex & other )
	QPersistentModelIndex (const QModelIndex & index )
QPersistentModelIndex &	operator= (const QModelIndex & other )
QPersistentModelIndex &	operator= (QPersistentModelIndex && other )
QPersistentModelIndex &	operator= (const QPersistentModelIndex & other )
int	column () const
QVariant	data (int role = Qt::DisplayRole) const
Qt::ItemFlags	flags () const
bool	isValid () const
const QAbstractItemModel *	model () const
QModelIndex	parent () const
int	row () const
QModelIndex	sibling (int row , int column ) const
void	swap (QPersistentModelIndex & other )
const QModelIndex &	operator const QModelIndex & () const
bool	operator!= (const QPersistentModelIndex & other ) const
bool	operator!= (const QModelIndex & other ) const
bool	operator< (const QPersistentModelIndex & other ) const
bool	operator== (const QPersistentModelIndex & other ) const
bool	operator== (const QModelIndex & other ) const

uint	qHash (const QPersistentModelIndex & index , uint seed = 0)

详细描述

A QPersistentModelIndex is a model index that can be stored by an application, and later used to access information in a model. Unlike the QModelIndex class, it is safe to store a QPersistentModelIndex since the model will ensure that references to items will continue to be valid as long as they can be accessed by the model.

It is good practice to check that persistent model indexes are valid before using them.

注意： You cannot store a QStandardItemModel 's QPersistentModelIndex in one of the model's items.

另请参阅 模型/视图编程 , QModelIndex ，和 QAbstractItemModel .

成员函数文档编制

QPersistentModelIndex:: QPersistentModelIndex ( QPersistentModelIndex && other )

Move-constructs a QPersistentModelIndex instance, making it point at the same object that other 所指向的。

该函数在 Qt 5.2 引入。

QPersistentModelIndex:: QPersistentModelIndex (const QPersistentModelIndex & other )

Creates a new QPersistentModelIndex that is a copy of the other persistent model index.

QPersistentModelIndex:: QPersistentModelIndex (const QModelIndex & index )

Creates a new QPersistentModelIndex that is a copy of the model index .

QPersistentModelIndex &QPersistentModelIndex:: operator= (const QModelIndex & other )

Sets the persistent model index to refer to the same item in a model as the other model index.

QPersistentModelIndex &QPersistentModelIndex:: operator= ( QPersistentModelIndex && other )

移动赋值 other 到此 QPersistentModelIndex 实例。

该函数在 Qt 5.2 引入。

QPersistentModelIndex &QPersistentModelIndex:: operator= (const QPersistentModelIndex & other )

Sets the persistent model index to refer to the same item in a model as the other persistent model index.

int QPersistentModelIndex:: column () const

Returns the column this persistent model index refers to.

QVariant QPersistentModelIndex:: data ( int role = Qt::DisplayRole) const

返回数据为给定 role for the item referred to by the index.

另请参阅 Qt::ItemDataRole and QAbstractItemModel::setData ().

Qt::ItemFlags QPersistentModelIndex:: flags () const

Returns the flags for the item referred to by the index.

该函数在 Qt 4.2 引入。

bool QPersistentModelIndex:: isValid () const

返回 true if this persistent model index is valid; otherwise returns false .

A valid index belongs to a model, and has non-negative row and column numbers.

另请参阅 model (), row ()，和 column ().

const QAbstractItemModel *QPersistentModelIndex:: model () const

Returns the model that the index belongs to.

QModelIndex QPersistentModelIndex:: parent () const

Returns the parent QModelIndex for this persistent index, or an invalid QModelIndex if it has no parent.

另请参阅 sibling () 和 model ().

int QPersistentModelIndex:: row () const

Returns the row this persistent model index refers to.

QModelIndex QPersistentModelIndex:: sibling ( int row , int column ) const

返回同级在 row and column or an invalid QModelIndex if there is no sibling at this position.

另请参阅 parent ().

void QPersistentModelIndex:: swap ( QPersistentModelIndex & other )

Swaps this persistent modelindex with other 。此函数非常快且从不失败。

该函数在 Qt 5.0 引入。

const QModelIndex &QPersistentModelIndex:: operator const QModelIndex & () const

Cast operator that returns a const QModelIndex &.

bool QPersistentModelIndex:: operator!= (const QPersistentModelIndex & other ) const

返回 true if this persistent model index is not equal to the other persistent model index; otherwise returns false .

该函数在 Qt 4.2 引入。

bool QPersistentModelIndex:: operator!= (const QModelIndex & other ) const

返回 true if this persistent model index does not refer to the same location as the other model index; otherwise returns false .

bool QPersistentModelIndex:: operator< (const QPersistentModelIndex & other ) const

返回 true if this persistent model index is smaller than the other persistent model index; otherwise returns false .

The internal data pointer, row, column, and model values in the persistent model index are used when comparing with another persistent model index.

该函数在 Qt 4.1 引入。

bool QPersistentModelIndex:: operator== (const QPersistentModelIndex & other ) const

返回 true if this persistent model index is equal to the other persistent model index; otherwise returns false .