QObjectCleanupHandler(3) Watches the lifetime of multiple QObjects


#include <qobjectcleanuphandler.h>

Inherits QObject.

Public Members

QObjectCleanupHandler ()

~QObjectCleanupHandler ()

QObject * add ( QObject * object )

void remove ( QObject * object )

bool isEmpty () const

void clear ()


The QObjectCleanupHandler class watches the lifetime of multiple QObjects.

A QObjectCleanupHandler is useful whenever you need to know when a number of QObjects that are owned by someone else have been deleted. This is important, for example, when referencing memory in an application that has been allocated in a shared library.


class FactoryComponent : public FactoryInterface, public QLibraryInterface

QObject *createObject();

bool init();
void cleanup();
bool canUnload() const;

QObjectCleanupHandler objects;

// allocate a new object, and add it to the cleanup handler
QObject *FactoryComponent::createObject()
return objects.add( new QObject() );

// QLibraryInterface implementation
bool FactoryComponent::init()
return TRUE;

void FactoryComponent::cleanup()

// it is only safe to unload the library when all QObject's have been destroyed
bool FactoryComponent::canUnload() const
return objects.isEmpty();

See also Object Model.


QObjectCleanupHandler::QObjectCleanupHandler ()

Constructs an empty QObjectCleanupHandler.

QObjectCleanupHandler::~QObjectCleanupHandler ()

Destroys the cleanup handler. All objects in this cleanup handler will be deleted.

QObject * QObjectCleanupHandler::add ( QObject * object )

Adds object to this cleanup handler and returns the pointer to the object.

void QObjectCleanupHandler::clear ()

Deletes all objects in this cleanup handler. The cleanup handler becomes empty.

bool QObjectCleanupHandler::isEmpty () const

Returns TRUE if this cleanup handler is empty or if all objects in this cleanup handler have been destroyed; otherwise return FALSE.

void QObjectCleanupHandler::remove ( QObject * object )

Removes the object from this cleanup handler. The object will not be destroyed.


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Generated automatically from the source code.


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