Contains a pointer to a QObject. More...

Public Methods
	QPointer ()

	QPointer (const QPointer &other) = default

	QPointer (QPointer &&other) = default

	QPointer (T *ptr)

	~QPointer () = default

void	clear ()

T *	data () const

bool	isNull () const

	operator T * () const

bool	operator!= (const QPointer &other) const

bool	operator!= (const T *ptr) const

T &	operator* () const

T *	operator-> () const

QPointer &	operator= (const QPointer &other) = default

QPointer &	operator= (QPointer &&other) = default

QPointer< T > &	operator= (T *ptr)

bool	operator== (const QPointer< T > &other) const noexcept

bool	operator== (const T *ptr) const

Detailed Description

template<class T>
class QPointer< T >

The QPointer class contains a pointer which can only point to a QObject or a child of QObject. The internal pointer is very similar to a weak pointer. However, there is no reference count in a QPointer, it is maintained in the QObject class. When a QObject or a class which inherits from QObject is deleted this class will contain a nullptr.

QPointer can never be used in a thread safe manner and should only be used in single threaded applications. From multi-threaded applications use a QSharedPointer with a QWeakPointer.

Example

QPointer<QLabel> label = new QLabel;
label->setText("&Status:");
 
if (label != nullptr) {
   label->show();
}

Constructor & Destructor Documentation

template<class T >

QPointer< T >::QPointer ( )

inline

Constructs QPointer which contains a null pointer.

template<class T >

QPointer< T >::QPointer ( T * ptr )

inlineexplicit

Constructs a QPointer which points to the same object which ptr points to. The template parameter T must inherit from QObject.

template<class T >

QPointer< T >::~QPointer ( )

default

Destroys the pointer.

template<class T >

QPointer< T >::QPointer ( const QPointer< T > & other )

default

Copy constructs a new QPointer from other.

template<class T >

QPointer< T >::QPointer ( QPointer< T > && other )

default

Move constructs a new QPointer from other.

Method Documentation

template<class T >

void QPointer< T >::clear ( )

inline

Sets the current QPointer object to a null pointer.

See also: isNull()

template<class T >

T * QPointer< T >::data ( ) const

inline

Returns a raw pointer to the current object. The template parameter T must inherit from QObject.

template<class T >

bool QPointer< T >::isNull ( ) const

inline

Returns true if the referenced object has been destroyed or if there is no referenced object, otherwise returns false.

See also: clear()

template<class T >

QPointer< T >::operator T * ( ) const

inline

This method converts a QPointer to a raw pointer.

template<class T >

bool QPointer< T >::operator!= ( const QPointer< T > & other ) const

Returns true if this QPointer is not equal to other, otherwise returns false.

template<class T >

bool QPointer< T >::operator!= ( const T * ptr ) const

Returns true if this QPointer is not equal to ptr, otherwise returns false.

template<class T >

T & QPointer< T >::operator* ( ) const

inline

Dereferences this QPointer and returns the object it points to. If the QPointer is a nullptr the behavior is undefined.

template<class T >

T * QPointer< T >::operator-> ( ) const

inline

Dereferences this QPointer and returns a raw pointer to the object it points to. If the QPointer is a nullptr the behavior is undefined.

template<class T >

QPointer & QPointer< T >::operator= ( const QPointer< T > & other )

default

Copy assigns from other and returns a reference to this object.

template<class T >

QPointer & QPointer< T >::operator= ( QPointer< T > && other )

default

Move assigns from other and returns a reference to this object.

template<class T >

QPointer< T > & QPointer< T >::operator= ( T * ptr )

inline

Assigns ptr to this QPointer.

template<class T >

bool QPointer< T >::operator== ( const QPointer< T > & other ) const

inlinenoexcept

Returns true if this QPointer is equal to other, otherwise returns false.

template<class T >

bool QPointer< T >::operator== ( const T * ptr ) const

Returns true if this QPointer is equal to ptr, otherwise returns false.

Public Methods

Detailed Description

template<class T> class QPointer< T >

Example

Constructor & Destructor Documentation

Method Documentation

template<class T>
class QPointer< T >