Question

Week 7, ex 4.3
I don't get what i'm doing wrong
win = GraphWin("Tetrominoes", 150, 150)
point = Point(1, 1)
color = 'black'

def Block(Rectangle):
def __init__(self, point1, color = 'black'):
self.canvans = Rectangle(point, Point(point.x + 20, point.y + 20))
self.canvans.setFill(color)

def draw(self, win):
self.canvans.draw(win)

rect = Block(point)
rect.draw(win)
win.mainloop()


And result:
File "E:/Python/test1/Ex4.3.py", line 26, in rect.canvans.draw(win) AttributeError: 'NoneType' object has no attribute 'canvans'

Answer 1

you want to define Block as a class, rather than a function:

class Block: # no argument is needed here

and then use either point or point1 consistantly between your
self__init__ function and your rectangle definition.

Answer 2

Should the class not be derived from Rectangle?

class Block(Rectangle):

There its also a typo: canvans should be canvas.

HTH.

Answer 3

Oh. I need more sleep.
I had to write "class Block" instead of "def Block".

Answer 4

:-)