Re: [wxperl-users] XRC Subclassing and control initialisation

[John R. <jr...@ce...>]

On Nov 7, 2006, at 6:03 AM, Mark Wardell wrote:

> Hi All,
>
> **Warning - fairly long post - patience required.
>
> In another attempt at using subclassed control in XRC I come  
> unstuck with code initialisation.
> In the new() method the windows have not been created so the window  
> hierarchy does not exist, so calls like GetParent() do not work. I  
> tried to init() my derived TreeCtrl by putting AddRoot() and  
> AppendItem() calls in the new() method but this did not work  
> (nothing appears in the tree).
>
> So I started looking around and found this page below in the  
> wxPython wiki which sums up the situation nicely. I recommend this  
> wiki to all wxPerl people as it contains a huge amount of  
> information that can be adapted for wxPerl developers, I often  
> visit looking for new info.
>
> http://wiki.wxpython.org/index.cgi/SubclassingListCtrlWithXrc
>
> The key area here is binding to the EVT_WINDOW_CREATE event. I  
> could not find this in the wxPerl sources but there is a EVT_CREATE  
> event defined on line 929 in Constant.xs. So I created the  
> following sub in my class as is the normal way as seen in Event.pm:
>
> sub EVT_CREATE($$) { $_[0]->Connect( -1, -1, &Wx::wxEVT_CREATE, $_ 
> [1] ) }
>
> So now in my code I can bind to the event using:
>
> EVT_CREATE( $self, \&OnCreateWindow );
>
> Then I can put my code in my derived class like below:
>
> sub OnCreateWindow { # own code goes here }
>
> This seems to work perfectly although I haven't had much time to  
> test and find any pitfalls.
> Has anyone alse tried using this technique?
> Does this sound like a reasonable solution Mattia? (Nobody  
> understand the event tables and refcounting like you)
>
> If I find this works without problems then I will look at a generic  
> way of providing this functionality for ALL objects created using  
> XRC subclassing.
>
> Hope this helps others that find themselves in a similar position.
>
> Regards
> Mark
>


Mark,

Sounds too complicated, so I must be missing something. Could you  
post some code snippets which show why the approach documented in
http://wxperl.pvoice.org/kwiki/index.cgi?SubclassingXRC
doesn't work?

Regards,
John Ralls