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 | + | [[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. --> | ||
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| + | |update-timestamp= <!-- After significant update: YYYYMMDD --> | ||
| + | |creationdate= 20-Jun-2010 | ||
| + | |author= [[User:Gnuton]] | ||
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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> | ||
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:MeeGo Harmattan]] [[Category:Symbian]] | [[Category:Qt]][[Category:MeeGo Harmattan]] [[Category:Symbian]] | ||
Revision as of 15:36, 23 July 2012
Article Metadata
Compatibility
Platform(s): All
Article
Keywords: Qt, deleteLater
Created: gnuton
(20 Jun 2010)
Last edited: hamishwillee
(23 Jul 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()
