[Catalyst] Re: questions on Reaction

[Matt S Trout]

On 2 Jan 2007, at 20:10, Daniel McBrearty wrote:

> OK. It is a good idea to make sure everything in the view goes through
> the I18N code, for sure. I'd like to merge what we are doing there
> with the cat plugin, but tat can wait ...
>
> next questions, about the Root.pm of the example app ... :
>
> 1.
>
> use base 'Reaction::UI::RootController';
> use Reaction::Class;
> use aliased 'Reaction::UI::ViewPort';
>
> do these HAVE to be in Root.pm?
>
> I just want to use this stuff in my admin code at the moment ... say
> it all sits in under MyApp::Controller::Admin ... can I just put these
> there?

They need to be in an appropriate namespace to supply begin and end  
actions. If all your reaction controllers are under ::Admin:: then  
that's fine - that's usually where we start when doing conversions  
(or where we stop when writing hybrids :)

> 2.
>
> __PACKAGE__->config(
>  view_name => 'XHTML',
>  window_title => 'Reaction Test App',
>  namespace => '',
> );
>
> sub base :Chained('/') :PathPart('') :CaptureArgs(0) {
>  my ($self, $c) = @_;
>  $self->push_viewport(ViewPort, layout => 'xhtml');
> }
>
> I'm just not getting this bit. WHy do I want your XHTML view (it
> happens that I use xhtml anyway ... ) but what's it all about?

You need to be using a view that inherits from  
Reaction::UI::Renderer::XHTML; it does a few bits and pieces above  
and beyond the standard TT view that are required for everything to  
work, and will likely soon to rather more above and beyond as layout  
classes get added to help extract even more logic out of the templates.

> 3. the root action is using a viewport, pushing the template name onto
> it ... what does a viewport actually do over, say, a standard TT
> template?

A viewport is nothing like a template - a viewport object provides a  
viewport onto a particularly model display or mutation and  
encapsulates all the logic required for handling events from the user  
and altering the data visible to the view/layout stuff appropriately.

In this case the viewport doesn't actually provide any data in and of  
itself - it's there as a placeholder for the xhtml document layout to  
hang off. The ListView and ActionForm viewports are probably more  
educational in terms of the point of such objects.

-- 
Matt S Trout, Technical Director, Shadowcat Systems Ltd.
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