f...@slick.airforce-one.org wrote:
Jean-Michel Pichavant <jeanmic...@sequans.com> wrote:
Always post working code, or at least something we can paste in the
python interpreter (even if it's buggy)
Ok, noted.
class A:
class B:
x=2
class C:
def __init__(self):
print A.B.x
c = A.C()
2
Good, thanks.
I've made further tests and here is what I have come to:
class zoneDeDessin(gtk.DrawingArea):
xmin = -5.5
xmax = 5.5
ymin = -5.5
ymax = 5.5
class Handle:
def __init__(self, xEcran, yEcran):
(self.xEcran, self.yEcran) = (xEcran, yEcran)
(self.xRepere, self.yRepere) = (zoneDeDessin.XdeLEcranAuRepere(xEcran),
zoneDeDessin.YdeLEcranAuRepere(yEcran))
def __init__(self):
gtk.DrawingArea.__init__(self)
(self.largeur, self.hauteur) = (0,0)
def expose(self, widget, event):
rect = self.get_allocation()
(self.largeur, self.hauteur) = (rect.width, rect.height)
def XdeLEcranAuRepere(self, x):
return zoneDeDessin.xmin+x*(zoneDeDessin.xmax-zoneDeDessin.xmin)/float(self.largeur)
def YdeLEcranAuRepere(self, y):
return
zoneDeDessin.ymax+y*(zoneDeDessin.ymin-zoneDeDessin.ymax)/float(self.hauteur)
I have further code that should add a Handle when I double-click on
the screen.
However I get this error when executing:
Traceback (most recent call last):
File "./zoneDeDessin.py", line 161, in boutonRelache
zoneDeDessin.Courbe.ajouterUnHandle(self.courbeCourante, event.x, event.y)
File "./zoneDeDessin.py", line 36, in ajouterUnHandle
self.listeDesPoints.append(zoneDeDessin.Handle(xEcran, yEcran))
File "./zoneDeDessin.py", line 22, in __init__
(self.xRepere, self.yRepere) = (zoneDeDessin.XdeLEcranAuRepere(xEcran),
zoneDeDessin.YdeLEcranAuRepere(yEcran))
TypeError: unbound method XdeLEcranAuRepere() must be called with zoneDeDessin
instance as first argument (got float instance instead)
I understand the error (XdeLEcranAuRepere is an instance method, not a
class method), but I don't see how to fix it, except by making largeur
and hauteur class variables...
Any hint?
Thanks!
Quite simple in fact,
XdeLEcranAuRepere is an instance method (any method with self as 1st parameter
is an instance method).
However you called it as a class method: zoneDeDessin.XdeLEcranAuRepere(xEcran)
Just change that code to self.XdeLEcranAuRepere(xEcran). 'self' allows you to
access attributes and methods of an instance.
Also don't code in french, you use meaningful names which is good, but they're
meaninful only to french speaking people. That will reduce the help you can't
get in this international list for instance.
Another detail, my guess is that
xmin = -5.5
xmax = 5.5
ymin = -5.5
ymax = 5.5
should be instance attributes not class attributes (you don't want 2 instances
of zoneDeDessin sharing the same xmin value).
A classic pattern for default values is:
class DrawArea:
DFT_XMIN = -5.5
DFT_XMAX = 5.5
DFT_YMIN = -5.5
DFT_YMAX = 5.5
def __init__(self, xmin=None, xmax=None, ymin=None, ymax=None):
self.xmin=xmin
self.xmax=xmax
self.ymin=ymin
self.ymax=ymax
for attribute in ['xmin', 'xmax', 'ymin', 'ymax']:
if getattr(self, attribute) is None: # then let's assign the default value
setattr(self, attribute, getattr(self, 'DFT_' +
attribute.upper())) # there's a little bit of magic here, it could be improved
but this is not the purpose here
d1=DrawArea()
print 'd1 ', d1.__dict__
d2=DrawArea(xmax=8)
print 'd2 ', d2.__dict__
execution output:
d1 {'xmin': -5.5, 'ymin': -5.5, 'ymax': 5.5, 'xmax': 5.5}
d2 {'xmin': -5.5, 'ymin': -5.5, 'ymax': 5.5, 'xmax': 8}
JM
PS : to those how would wonder why not include self.xmin=xmin into the
'for attribute' loop, it's just to not mess with most linter(including
pylint), and for attributes, it's always a good think to 'declare' them
explicitly in the __init__ method.
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