Matthias said:
Hello,
I have a Canvas-Widget and will use as a "array of pixel". At Positon
x,y I print a rectangle with a special color. I give the rectangle no
objectname. Then I will ask the "root-Canvas-Widget" for the color in
position x,y like:
color=cw.cget('bg',x,y)
I need HELP
)
You can get the tags for the objects at position (x, y) via:
tags = cw.find_overlapping(x, y, x, y)
(or maybe cw.find_overlapping(x, y, x+1, y+1); I didn't test...)
If you're sure you've got only one object overlapping this position, you can
then do:
color = cw.itemcget(tags[0], 'bg')
BTW, using a Canvas as an array of pixels does not seem like a good idea to me:
canvases are intended to do vector drawing, not bitmap...
Are you aware that you can do what you want via images? Example:
--images.py---------------------
from Tkinter import *
root = Tk()
cnv = Canvas(root)
cnv.pack(side=TOP)
img = PhotoImage(width=100, height=100)
cnv.create_image(0, 0, anchor=NW, image=img)
def plot():
for i in range(10, 90):
img.put('#ff0000', to=(i, i))
img.put('#00ff00', to=(i, 100 - i))
def read():
for i in range(0, 100):
print img.get(i, 40)
Button(root, text='Plot', command=plot).pack(side=LEFT)
Button(root, text='Read', command=read).pack(side=LEFT)
root.mainloop()
--------------------------------
This is much easier to do (except maybe for the strange format of the color
returned by img.get) and images are intended for this purpose, so you're less
likely to have any problem.
HTH
