[z3-five] Adapter and View insanity

[Chris Withers]

Martin Aspeli wrote:
> When you are passing context in like this, you may want to think about having 
> multi-adapters that adapt the object being rendered and the context it's 
> rendered in. 

Nah, in this case, context could have easilly been "target" with the 
adapted object being "source". I need the specific instance, so I see 
where you're coming from, but no, it's not what I should do here...

>> <p tal:content="structure 
>> python:modules['Products.MyProduct.interfaces'].IRender(item).render
> (context,title='Foo')"/>
> 
> If the template was really a view, registered with <browser:page>, you'd have 
> a class in which you cuold put this logic:
> 
> class MyView(BrowserView):
> 
>     def render(self, item, title):
>         return IRender(item).render(self.context, title)
> 
> And then in the template:
> 
>   tal:replace="python:view.render(item, title)"

Ah yes, that is nice, but some of the places where it's used are not 
conducive to being turned into views ;-)

So, I think I'll stick with @@render for now, no matter how much I bitch 
about it ;-)

>> But there's still a few problems:
>>
>> 1. I'm instantiating yet another class every time I just want to adapt
>>     something and call a method
> 
> So you could instantiate once in a tal:define and put the logic in a method 
> rather than in __call__().

Yuk.

>> 2. I can't pass in a title or explicit context. I have to work the
>>     context out using acquisition 
> 
> Again solved by a method.

True enough, hopefully I won't need this...

>> 3. I'm deeply disturbed as to how instances of my Render view class come
>>     to magically have a context attribute. wtf?
> 
> It's a browser view. The ZCML directive injects a base class. Yes, it's nasty, 
> which is why it's normally saner to explicitly inherit from 
> Products.Five.browser.BrowserView.

See, I don't really understand what inheriting from BrowserView buys you...

Why is the magic there?!

> You can use restrictedTraverse() if you wish, but really you are doing:
> 
> from zope.component import getMultiAdapter
> render = getMultiAdapter((context, view), name='render')
> print render()

What's 'view' in the above?

cheers,

Chris

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