How to delete a QObject derived class from within one of its own methods
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| − | {{ | + | [[Category:Qt]][[Category:How To]][[Category:Code Snippet]] |
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| + | |devices= <!-- Devices tested against - e.g. ''devices=Nokia 6131 NFC, Nokia C7-00'') --> | ||
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|platform= All | |platform= All | ||
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| − | | | + | |capabilities= <!-- Capabilities required by the article/code example (e.g. Location, NetworkServices. --> |
|keywords= Qt, deleteLater | |keywords= Qt, deleteLater | ||
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| + | |creationdate= 20-Jun-2010 | ||
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In order to delete a QObject-derived class from one of its own methods, developers have to use | In order to delete a QObject-derived class from one of its own methods, developers have to use | ||
| − | <code cpp> | + | <code cpp-qt> |
deleteLater(); | deleteLater(); | ||
</code> | </code> | ||
Since this is a public slot, it can be connected to a signal or it can be just called in any method of the class. | Since this is a public slot, it can be connected to a signal or it can be just called in any method of the class. | ||
| − | There are no problem if a signal or a method calls more than one time [http://doc.qt.nokia.com/4.6/qobject.html#deleteLater | + | There are no problem if a signal or a method calls more than one time [http://doc.qt.nokia.com/4.6/qobject.html#deleteLater QObject::deleteLater()] |
| − | Beginner developers sometimes | + | Beginner developers sometimes use |
| − | <code cpp> | + | <code cpp-qt> |
delete this; | delete this; | ||
</code> | </code> | ||
| − | and this is dangerous since the Qt event loop could invoke a method of the deleted class. Hence, the application or library | + | and this is dangerous since the Qt event loop could invoke a method of the deleted class. Hence, the application or library will crash. |
* Related Qt Documentation link | * Related Qt Documentation link | ||
Qt 4.6 [http://doc.qt.nokia.com/4.6/qobject.html#deleteLater deleteLater()] | Qt 4.6 [http://doc.qt.nokia.com/4.6/qobject.html#deleteLater deleteLater()] | ||
| − | [[Category:Qt]] | + | [[Category:Qt]][[Category:MeeGo Harmattan]] [[Category:Symbian]] |
Latest revision as of 04:17, 11 October 2012
Article Metadata
Compatibility
Platform(s): All
Article
Keywords: Qt, deleteLater
Created: gnuton
(20 Jun 2010)
Last edited: hamishwillee
(11 Oct 2012)
In order to delete a QObject-derived class from one of its own methods, developers have to use
deleteLater();
Since this is a public slot, it can be connected to a signal or it can be just called in any method of the class.
There are no problem if a signal or a method calls more than one time QObject::deleteLater()
Beginner developers sometimes use
delete this;
and this is dangerous since the Qt event loop could invoke a method of the deleted class. Hence, the application or library will crash.
- Related Qt Documentation link
Qt 4.6 deleteLater()
