如何将通过比例获得的新值传递给另一个函数？

Question

我在 Python2.7，我尝试将从 scale 获得的值传输到另一个必须响应点击的函数。

from tkinter import * 

fenetre = Tk()

def other(ev):
    m=2
    l=3
    vol_piano=maj()
    print(vol_piano)

def maj(newvalue):
    vol_piano = newvalue
    print(vol_piano)
    return vol_piano

value = DoubleVar()
scale = Scale(fenetre, variable=value, orient ='vertical', from_ = 0, to= 100,
              resolution = 1, tickinterval= 5, length=400, label='Volume Piano',command=maj)
scale.pack(side=RIGHT)

canvas = Canvas(fenetre, width=100, height=400, bg="white")
curseur1 = canvas.create_line(0, 0, 0, 0)
canvas.pack(side=LEFT)
canvas.bind("<Button-1>", other)

fenetre.mainloop()

问题是我无法使用 return，因为我的函数 maj() 在参数中有新值随比例获得。

Answer 1

您可以将 vol_piano 设为全局变量。每当 Scale 移入 maj() 函数时更新它的值。每当单击 canvas 时，只需打印出 vol_piano.

的值

import tkinter as tk

fenetre = tk.Tk()

<b>vol_piano = None</b>

def other(ev):
    <b>global vol_piano</b>
    print(vol_piano)

def maj(newvalue):
    <b>global vol_piano
    vol_piano = newvalue</b>

value = tk.DoubleVar()
scale = tk.Scale(fenetre, variable=value, orient ='vertical', from_ = 0, to= 100,
              resolution = 1, tickinterval= 5, length=400, label='Volume Piano',command=maj)
scale.pack(side="right")

canvas = tk.Canvas(fenetre, width=100, height=400, bg="white")
canvas.pack(side="left")
canvas.bind("<Button-1>", other)

fenetre.mainloop()

如何将通过比例获得的新值传递给另一个函数？

How to transmit a new value got with a scale to another function?

python

tkinter

python-2.7

tkinter-scale