Re: Drawing with NSCell or NSView and reducing -drawRect: clutter?

[Fred Kiefer]

Daniel J Farrell wrote:
> Hello,
> 
> (please see below for the reasoning behind these questions)
> 
> 1) Can I tell an NSCell to draw paths?
>
You don't need to tell the NSCell, just draw the path inside its
drawInteriorWithFrame:inView: method. Here the view (actually an
NSControl subclass) already has been set as the current drawing target.

> 2) Is it a good idea to reduce clutter in -drawRect: by using simple
> helper objects to draw? I would find this aesthetically more pleasing
> compared to just adding methods to the NSView subclass. As for the
> former, I can have a one-to-one relationship between custom drawing
> objects and model objects (see below for more details about this). i.e.
> a model object is drawn using a corresponding drawing object.
> 
Nice, this surely works with GNUstep, but we don't have any special
support for it.

> From reading the docs it seems that NSCell is a way to do simple drawing
> inside a parent NSView. However, it seems to centre around drawing
> images and text.
> 
If you don't use the border functionality and you don't need multiple
drawing targets at once, then there isn't much difference for you
between using an NSView or an NSCell.

> What I'm actually doing is trying to draw the axis of a graph. I have a
> simple model object that describes the axis (tic marks along an axis)
> and just want a graphical representation of it, e.g. a line with the tic
> marks at appropriate intervals. Have a look here for the model class,
> http://www.boyfarrell.com/code/chocplot/doc/
> 
> I was hoping to have a simple drawing class that I can initialise with
> my axis model, such that it will draw in the appropriate place on my
> NSView.
> 
No, there isn't any class for this in GNUstep, the closest we have got
is NSRulerView. Perhaps you could have a look there.

Fred