Re: Themes GNUstep

[Nicolas Roard]

On 2002-07-31 08:34:39 -0600 Adam Fedor <fedor@doc.com> wrote:

> > - some informations needed for a theme isn't always available (as in NSButtons, 
> >  the style (NSRadioButtons, etc.) isn't stocked, which render a theme 
> > implementation
> >     quite hazardous)
>
> There's a function in Gorm (Palettes/2Controls/inspectors.m) which returns the 
> button type for a button. Perhaps we could put that in gui if it is useful.

Yes PY told me about it, I must look at it.
But I thought that it could be simpler to stock the buttonType in the 
NSButtonCell
when setted by setButtonType ?

> > - I must currently re-implement drawRect functions (or similars) to drawing the 
> > widgets
> >     backgrounds, which  force me to reimplement the entire drawRect function, 
> > and add my  code... if the code of drawRect change in the gnustep cvs, I must 
> > update it in thoses  themes bundles. Could it be possible to have a dedicated 
> > function for drawing the  background of a widget ?  which will be called 
> > instead of the [backgroundColor set];  NRectFill (cellFrame); ?
> >
> > I'd like to make those changes, but I don't want to break something ;)
> > So what are you thinking about this ?
>
> Well, I'd like to make themes easier also, but I don't know the best way to do 
> it. Perhaps redoing the background and frame drawing functions so they can be 
> overridden, or perhaps specific (and documented) drawing methods for different 
> widgets. I was hoping someone could take the time to look at how other systems 
> implement themes and adopt that to GNUstep.

Previously, what I did was simply to test/validate/understand the concept :) so 
I'm currently working on a complete theme (gradients like thoses in wmaker).
It permits me to better understand the drawings relations between all the 
widgets, etc. After that, I should have a better idea of how to redesign 
(eventually) the classes
to simplify a theme writing, or if we could simply keep things as they are, and 
just write a howto ;)

As far as I know, there are two methods used in others systems (KDE/Gtk) :
- implement new drawings functions (.so) (what I did)
- use a "theme engine" and skin the interface with pixmaps
Reimplement drawings functions are more complex to do, but faster at
execution; A theme engine based on pixmap should allow users to create
theme simply, but it will be slower.
I'll try to implement a pixmap theme engine in the future.

--
Nicolas Roard <nicolas@roard.com>
http://info.xdev.org/projets/gsftp
the linux philosophy is laugh in the face of danger. Oops. Wrong one. 'Do it 
yourself'. That's it.