Re: GNUstep themes [Was: Obscure timing issue]

[Richard Frith-Macdonald]

On 12 Dec 2008, at 09:06, Andreas Schik wrote:

> >
> No. As Class2 inherits from Class1, each subclass of Class2 will
> inherit from Class1 as well.

That was my suggestion ... Fred said 'these classes will inherit from  
another'

> And in how far would this be different? I think you both mean
> basically the same.

Maybe so.

> The current solution at least does not allow the development of new
> mechanisms that do not want to use tiles at all.

It does ... the new mechanisms simply don't need to use tiles.  I have  
test code that does that.

> Each call to super
> will result at least in checking for tiles before falling back to the
> low-level drawing.

True ... but that's invisible to the developer and a negligible  
overhead and it's a requirement for the general case (for other people  
to be able to alter/enhance the theme any way they like).

If a theme developer really wants to prevent other people from  
producing their own themes based on his/her theme than they can  
override the drawing code completely, but otherwise (what I'd consider  
a well behaved theme) their code would call the superclass  
implementation when thy don't want to do anything special.
In fact, it's perfectly reasonable to implement a theme in which a  
drawing method will do some preliminary setup, then call the  
superclass implementation, then do some extra drawing on top of that.