[Seaside] Callbacks on collection tags

[Lukas Renggli]

> In the previous example, the unordered list callback block, when
> executed, knows the "selected" item.
> But there's no way to know it in the updater block.

In the above code you define the onClick action on the list, therefor
you only knowledge is that the user clicked in the area of the ul-tag.

Fore sake of correctness: It is possible to find out what element was
originally clicked by looking at the JavaScript event object. However
this is not easily feasible (yet) by only writing Smalltalk code.

Cheers,
Lukas

-- 
Lukas Renggli
http://www.lukas-renggli.ch