creating a loop to draw tkinter canvas lines

[stabzagg]

Hey there,

I have written some code to draw a grid on a canvas but the code is far to long.. so I was wondering what the most efficient way to write my code would be.

self._canvas = Canvas(self, width = 450, height = 450, bg ='white', highlightthickness = 0)
        self._canvas.pack(padx = 20, pady = 20)
        self._canvas.create_line(0, 0, 450, 0, width = 5.0)
        self._canvas.create_line(50, 0, 50, 450)
        self._canvas.create_line(100, 0, 100, 450)
        self._canvas.create_line(150, 0, 150, 450, width = 5.0)
        self._canvas.create_line(200, 0, 200, 450)
        self._canvas.create_line(250, 0, 250, 450)
        self._canvas.create_line(300, 0, 300, 450, width = 5.0)
        self._canvas.create_line(350, 0, 350, 450)
        self._canvas.create_line(400, 0, 400, 450)
        self._canvas.create_line(450, 0, 450, 450, width = 5.0)
        self._canvas.create_line(0, 0, 0, 450, width = 5.0)
        self._canvas.create_line(0, 50, 450, 50)
        self._canvas.create_line(0, 100, 450, 100)
        self._canvas.create_line(0, 150, 450, 150, width = 5.0)
        self._canvas.create_line(0, 200, 450, 200)
        self._canvas.create_line(0, 250, 450, 250)
        self._canvas.create_line(0, 300, 450, 300, width = 5.0)
        self._canvas.create_line(0, 350, 450, 350)
        self._canvas.create_line(0, 400, 450, 400)
        self._canvas.create_line(0, 450, 450, 450, width = 5.0)

Thanks :)

[Lardmeister]

You can create all the lines within one for loop. Your coordinates are incremented in given steps, so you can calculate them in each loop around. It might be simpler to do one for loop for horizontal lines and one for vertical lines.

[stabzagg]

Something along the lines of for the first loop?

for line in grid:
            if x1 % 50 == 0 and y1 == 0:
                if x2 % 50 == 0 and y2 == 450:
                    self._canvas.create_line()

Thanks for the reply

[sneekula]

Lardmeister suggested something much simpler, something like this:

# using the Tkinter canvas to
# draw a line from coordinates x1,y1 to x2,y2
# create_line(x1, y1, x2, y2, width=1, fill="black")

try:
    # Python2
    import Tkinter as tk
except ImportError:
    # Python3
    import tkinter as tk

root = tk.Tk()
root.title("drawing lines")

# create the drawing canvas
canvas = tk.Canvas(root, width=450, height=450, bg='white')
canvas.pack()

# draw horizontal lines
x1 = 0
x2 = 450
for k in range(0, 500, 50):
    y1 = k
    y2 = k
    canvas.create_line(x1, y1, x2, y2)

# draw vertical lines
y1 = 0
y2 = 450
for k in range(0, 500, 50):
    x1 = k
    x2 = k
    canvas.create_line(x1, y1, x2, y2)

root.mainloop()

[sneekula]

Got a goofy message and ended up with a duplicate, sorry folks!

[TrustyTony]

I would make it little clearer, what is logic of numbers and to make the subsquare thick lines, like original (for bigger squares, just change sq = 50 line)

# using the Tkinter canvas to
# draw a line from coordinates x1,y1 to x2,y2
# create_line(x1, y1, x2, y2, width=1, fill="black")
try:
    # Python2
    import Tkinter as tk
except ImportError:
    # Python3
    import tkinter as tk

root = tk.Tk()
root.title("drawing lines")

# create the drawing canvas
sq = 50
numsq = 9

thickevery = 3

normal = 1
wide = 3

canvas = tk.Canvas(root, width=numsq*sq, height=9*sq, bg='white')
canvas.pack()

# draw horizontal lines
x1 = 0
x2 = 9*sq
for k in range(0, sq*(numsq+1), sq):
    y1 = k
    y2 = k
    if k % thickevery: w = normal
    else: w = wide
    canvas.create_line(x1, y1, x2, y2, width=w)

# draw vertical lines
y1 = 0
y2 = 9*sq
for k in range(0, sq*(numsq+1), sq):
    x1 = k
    x2 = k
    if k % thickevery: w = normal
    else: w = wide
    canvas.create_line(x1, y1, x2, y2, width=w)

root.mainloop()

[morgadao]

Is possible to use a background image with tkinter canvas lines over it?
THANKS FOR THE HELP