[haiku-development] Re: Haiku, Qt and apps, oh my!

Qt in the backend uses the Observer/Subscriber/Notifier design pattern.
 Each widget maintains a list of 'subscribers', and on a given event, it
cycles through the list notifying all subscribers.  Trolltech built their
entire API around this philosophy.  It works for some scenarios, but is
expensive in others.  Trolltech back in 2000 used to publicly claim that
their design philosophy costs around 10% of the CPU performance, though with
newer CPU's this effect is smaller.  You do win with more manageable complex
code.

BeInc, however, adhered more to the "dont pay for what you dont need"
philosophy (that philosophy was very popular in the C++ camp back in the
90's, and still is).  You can manually implement an Observer patter on top
of your code if you wish, it's very trivial to do.

Cheers.


On Sat, Mar 28, 2009 at 3:19 PM, François Revol <revol@xxxxxxx> wrote:

>
> If done correctly it could be almost as native as real stuff...
> Besides, Qt is a rip off BeAPI, so it can't be that hard :)
>
> François.
>
>

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