Python - Tkinter (ttk) 动态创建一个进度条，其值会发生变化

Question

所以基本上我正在尝试制作多个进度条，每个进度条的值从 0 到 100 运行。但现在我的函数也可以访问其他函数的值，这看起来很奇怪。希望有人可以帮助我。谢谢:)

# -*- coding: utf-8 -*-
import tkinter.ttk as ttk
import tkinter as tk
from threading import Thread
import time

class Main(object):
    def __init__(self, master):
        self.master = master

        self.frame = tk.Frame(self.master, width=400, height=400)
        self.frame.pack(expand=True)

        self.button = tk.Button(self.frame, text="Add Bar", command=self.start_thread)
        self.button.pack(fill="y")

    def start_thread(self):
        self.t = Thread(target=self.add_bar)
        self.t.start()

    def add_bar(self):
        self.var = tk.IntVar()
        self.var.set(0)

        self.progessbar = ttk.Progressbar(self.frame, variable=self.var, orient=tk.HORIZONTAL, length=200)
        self.progessbar.pack()

        self.add_values(self.var)

    def add_values(self, var):
        self.variable = var
        for self.x in range(100):
            time.sleep(0.1)
            self.variable.set(self.x)


root = tk.Tk()
app = Main(root)
root.mainloop()

Answer 1

在您的原始代码中，self.var 是唯一存储加载栏进度的变量。由于 Main 对象只有一个实例，因此 self.var 只有一个实例，这会导致您描述的问题。为了解决这个问题，我建议为加载栏创建一个单独的类，如下所示：

# -*- coding: utf-8 -*-
import tkinter.ttk as ttk
import tkinter as tk
from threading import Thread
import time

class Main(object):
    def __init__(self, master):
        self.master = master

        self.frame = tk.Frame(self.master, width=400, height=400)
        self.frame.pack(expand=True)

        self.button = tk.Button(self.frame, text="Add Bar", command=lambda:self.createBar())
        self.button.pack(fill="y")

    def createBar(self):
        self.t = Thread(target=self.create)
        self.t.start()

    def create(self):
        newBar = LoadingBar(self.master, self.frame)

class LoadingBar(object):
    def __init__(self, master, frame):
        # Must use same Tkinter frame to add loading bars into
        self.master = master
        self.frame = frame
        self.add_bar()

    def start_thread(self):
        self.t = Thread(target=self.add_bar)
        self.t.start()

    def add_bar(self):
        self.var = tk.IntVar()
        self.var.set(0)

        self.progessbar = ttk.Progressbar(self.frame, variable=self.var, orient=tk.HORIZONTAL, length=200)
        self.progessbar.pack()

        self.add_values(self.var)

    def add_values(self, var):
        self.variable = var
        for self.x in range(100):
            time.sleep(0.1)
            self.variable.set(self.x)

root = tk.Tk()
app = Main(root)
root.mainloop()

在单独的线程中创建加载栏的每个实例可以获得所需的效果。

这是另一种方法（没有新类）：

# -*- coding: utf-8 -*-
import tkinter.ttk as ttk
import tkinter as tk
from threading import Thread
import time

class Main(object):
    def __init__(self, master):
        self.master = master

        self.frame = tk.Frame(self.master, width=400, height=400)
        self.frame.pack(expand=True)

        self.button = tk.Button(self.frame, text="Add Bar", command=self.start_thread)
        self.button.pack(fill="y")

    def start_thread(self):
        self.t = Thread(target=self.add_bar)
        self.t.start()

    def add_bar(self):
        var = tk.IntVar()
        var.set(0)

        progessbar = ttk.Progressbar(self.frame, variable=var, orient=tk.HORIZONTAL, length=200)
        progessbar.pack()

        self.add_values(var)

    def add_values(self, var):
        variable = var
        for x in range(100):
            time.sleep(0.1)
            variable.set(x)


root = tk.Tk()
app = Main(root)
root.mainloop()

注意：为每个线程创建局部变量，而不是实例变量，以避免覆盖实例变量。