QObjectCleanupHandler Class

The QObjectCleanupHandler class watches the lifetime of multiple QObjects. More...

Header: #include <QObjectCleanupHandler>
qmake: QT += core
Inherits: QObject

Public Functions

QObject *add(QObject *object)
void clear()
bool isEmpty() const
void remove(QObject *object)
  • 31 public functions inherited from QObject

Additional Inherited Members

  • 1 property inherited from QObject
  • 1 public slot inherited from QObject
  • 2 signals inherited from QObject
  • 11 static public members inherited from QObject
  • 9 protected functions inherited from QObject

Detailed Description

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.

To keep track of some QObjects, create a QObjectCleanupHandler, and add() the objects you are interested in. If you are no longer interested in tracking a particular object, use remove() to remove it from the cleanup handler. If an object being tracked by the cleanup handler gets deleted by someone else it will automatically be removed from the cleanup handler. You can delete all the objects in the cleanup handler with clear(), or by destroying the cleanup handler. isEmpty() returns true if the QObjectCleanupHandler has no objects to keep track of.

See also QPointer.

Member Function Documentation


Constructs an empty QObjectCleanupHandler.


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

See also clear().

QObject *QObjectCleanupHandler::add(QObject *object)

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

See also remove().

void QObjectCleanupHandler::clear()

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

See also isEmpty().

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.

See also add(), remove(), and clear().

void QObjectCleanupHandler::remove(QObject *object)

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

See also add().

© 2016 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners. The documentation provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners.