[
https://issues.apache.org/jira/browse/WICKET-3218?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13003750#comment-13003750
]
Chris Colman edited comment on WICKET-3218 at 3/8/11 3:34 AM:
--------------------------------------------------------------
+1 for onInitialize being overridable in pages. A 'post constructor' initialize
method is available in just about every GUI framework I've ever worked on OWL,
MFC, .net, AWT, Swing, Echo. Wicket is the first one I've ever used that
encourages the dangerous practice of adding child components while the parent
is only 'partially constructed' (ie. in a super class constructor).
I discussed this back in the old days ('07) in the context of a problem with
getVariation() that was overridden and hence caused problems when being called
during construction. The specific case of getVariation() was fixed but I still
feel that the onInitialize is a very good idea. With sufficient documentation
it won't be a problem for the newbies and anyone whose ever used any other GUI
framework will embrace it.
http://apache-wicket.1842946.n4.nabble.com/Lifecycle-issue-with-getVariation-td1928017.html
was (Author: chrisc):
+1 for onInitialize being overridable in pages. A 'post constructor'
initialize method is available in just about every GUI framework I've ever
worked on OWL, MFC, .net, AWT, Swing, Echo. Wicket is the first one I've ever
used that encourages the dangerous practice of adding child components while
the parent is only 'partially constructed' (ie. in a super class constructor).
I discussed this back in the old days ('07) in the context of a problem with
getVariation() that was overridden and hence called problems when being called
during constructor. The specific case of getVariation() was fixed but I still
feel that the onInitialize is a very good idea. With sufficient documentation
it won't be a problem for the newbies.
http://apache-wicket.1842946.n4.nabble.com/Lifecycle-issue-with-getVariation-td1928017.html
> Component#onInitialize is broken for Pages
> ------------------------------------------
>
> Key: WICKET-3218
> URL: https://issues.apache.org/jira/browse/WICKET-3218
> Project: Wicket
> Issue Type: Bug
> Components: wicket-core
> Affects Versions: 1.4.14
> Reporter: Carl-Eric Menzel
> Assignee: Igor Vaynberg
> Fix For: 1.5-RC1
>
> Attachments:
> 0001-delay-oninitialize-until-just-before-onconfigure.patch
>
>
> As first mentioned at
> http://mail-archives.apache.org/mod_mbox/wicket-dev/201012.mbox/%3c1291238699.1749.1408166...@webmail.messagingengine.com%3E
> , I think the current (Wicket 1.4.14) implementation of
> Component#onInitialize is broken for Pages. Pages get initialized as soon as
> the first component is added, which is correct. But this usually happens
> within the constructor of the page, which means that the page object isn't
> fully initialized yet. The entire point of having onInitialize, however, is
> to be able to do further work once all constructors have run. See
> https://github.com/duesenklipper/wicket-oninitialize for a quickstart that
> demonstrates the problem.
> Pedro Santos suggested in the above thread to just switch the entire object
> construction to onInitialize. I don't think this is a good idea, because
> 1) it is completely counter-intuitive
> 2) it is not always realistic to have an entire class hierarchy not using the
> constructor just because a subclass somewhere might want to use onInitialize
> 3) it is inconsistent with onInitialize behavior for all other (non-Page)
> components. Here I can easily mix work in the constructor with onInitialize.
> I propose the following patch:
> - override onInitialize in Page and make it final, so Pages can't use this
> any more. This should not cause any unnecessary breaking, since currently
> it's not working for pages anyway.
> - introduce Page#onPageInitialize to provide a safe alternative to
> onInitialize
> - make a special case for Page in Component's beforeRender to fire
> Page#onPageInitialize if necessary
> Yes, this is a bit of special casing for Page, but there's quite a lot of
> that needed for Page anyway. I think the impact of this should be minimal.
> My page includes documentation and a new testcase that verifies the new
> behavior. I modified the old ComponentInitializationTest to reflect the fact
> that Page doesn't get onInitialize any more.
--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira
