Dynamically add items to Tkinter Canvas
- by nick369
I'm attempting to learn Tkinter with the goal of being able to create a 'real-time' scope to plot data. As a test, I'm trying to draw a polygon on the canvas every time the 'draw' button is pressed. The triangle position is randomized. I have two problems:
There is a triangle on the canvas as soon as the program starts, why and how do I fix this?
It doesn't draw any triangles when I press the button, at least none that I can see.
CODE
from Tkinter import *
from random import randint
class App:
def __init__(self,master):
#frame = Frame(master)
#frame.pack(side = LEFT)
self.plotspc = Canvas(master,height = 100, width = 200, bg = "white")
self.plotspc.grid(row=0,column = 2, rowspan = 5)
self.button = Button(master, text = "Quit", fg = "red", \
command = master.quit)
self.button.grid(row=0,column=0)
self.drawbutton = Button(master, text = "Draw", command = \
self.pt([50,50]))
self.drawbutton.grid(row = 0, column = 1)
def pt(self, coords):
coords[0] = coords[0] + randint(-20,20)
coords[1] = coords[1] + randint(-20,20)
x = (0,5,10)
y = (0,10,0)
xp = [coords[0] + xv for xv in x]
yp = [coords[1] + yv for yv in y]
ptf = zip(xp,yp)
self.plotspc.create_polygon(*ptf)
if _name_ == "_main_":
root = Tk()
app = App(root)
root.mainloop()
The code is formatting strangely within the code tags, I have no idea how to fix this.
