Hi Alex, Igor and others,
this discussion is interesting to follow. GUI frameworks are hard...
Le 03/04/2016 16:58, Aliaksei Syrel a écrit :
And you lost me here.. That is complete nonsense.. from any perspective.
Can i unsee this code, please? :)
If I would say that we have defaultShape method and it can be overridden as:
defaultShape
^ BlShape new
fillPaint: (BlColorPaint new color: (Color yellow));
path: BlRectanglePath new
would it make you happy?
If you don't tell me there is a cost for creating a shape in athens,
I'll wonder if you're not asking me to optimise by caching a shape; and
that is over-engineering.
.. to me it feels like: okay, what we need to do, to prevent
overrides of our beloved default #drawOn: method.
You are wrong concerning preventing to override drawOn :)
I wonder if that "shape" thing is not something like the difference
between Roassal and Trachel: RT vs TR objects. And, yes, for me, the
RT/TR hierarchy is a reimplementation of objects over Athens, and the
end result is that it is easy to compose existing objects in Roassal and
hard to extend it.
Don't forget that there was a customer *requirement* concerning bloc:
Can we change how morph looks on fly? Can we create a rectangle morph
and change it's shape from rectangle to circle? Because it can nicely
show while presenting that *Pharo is live system*. I'm pretty sure Stef
said it once ago.
If that is your requirement, then this is bad.
It's a demo requirement with costly consequences. Does it apply in real
life in a system where recreating a complete Morph is so cheap (witness
FastTable!)? I'd say no.
Do you see how bloc story can nicely be told:
We have basic UI elements and each element has shape that can be
easily changed live. Shape is defined by a path which can be filled
or stroked using a paint. Complex elements can be created as
composition of elements with basic shapes (rectangle, circle).
Isn't it beautiful? :)
It is, but it tells of complexity: UI behavior composition (not only
graphics). Extending elements may also require extending shapes and
understanding how they interact and compose.
Regards,
Thierry
