更新ttk.Progressbar的最大值

Question

我正在努力解决一个看似简单的问题：我希望能够通过手动更改条目的值来更新tkinter中进度条的最大值。会发生什么是初始值100不会改变。好吧，我认为通过在方法set中调用count，我将能够更新最大值。它没用。问题是什么？

import tkinter as tk
from tkinter import ttk
from time import sleep

class Window():    
    def __init__(self, master):
        self.master = master
        self.configure()
        self.create_widgets()

    def configure(self):
        self.master.title('Progress bar')
        self.master.minsize(height=100, width=500)

    def create_widgets(self):
        self.progress = tk.DoubleVar()
        self.number = tk.StringVar()
        self.number.set('100')
        self.max = tk.IntVar()
        self.max.set(eval(self.number.get()))

        b1 = tk.Button(self.master, text='Count!', command=self.count)
        b1.pack()
        e1 = tk.Entry(self.master, textvariable=self.number, width=5)
        e1.pack()

        p = ttk.Progressbar(self.master, orient='horizontal', length=200, mode='determinate', variable=self.progress, value=1, maximum=self.max.get())
        p.pack()        

    def count(self):
        self.max.set(eval(self.number.get()))
        for i in range(eval(self.number.get())):
            sleep(0.01)
            print(i)
            self.progress.set(i)
            self.master.update()

def main():
    root = tk.Tk()
    app = Window(root)
    root.mainloop()

main()

Answer 1

你可能正在努力，因为你的问题过于复杂。为什么在不需要时使用3个单独的Variable类？目前，您要创建一个静态最大值为100的进度条，然后通过设置条目的值来更改该窗口中的进度。

这是一个更新进度条最大值的最小示例：

try:                        # In order to be able to import tkinter for
    import tkinter as tk    # either in python 2 or in python 3
    import tkinter.ttk as ttk
except ImportError:
    import Tkinter as tk
    import ttk


class RestartableProgress(tk.Frame):
    def __init__(self, master, *args, **kwargs):
        tk.Frame.__init__(self, master, *args, **kwargs)
        self.max_input = tk.Entry(self)
        self.restart_button = tk.Button(self, text="Restart",
                                                        command=self.restart)
        self.progressbar = ttk.Progressbar(self)
        self.max_input.pack()
        self.restart_button.pack()
        self.progressbar.pack()


    def restart(self):
        self.progressbar['value'] = 0
        self.progress()


    def progress(self):
        max_val = self.max_input.get()
        if max_val:
            self.progressbar['maximum'] = int(max_val)
            if self.progressbar['value'] < self.progressbar['maximum']:
                self.progressbar['value'] += 1
                self.after(10, self.progress)


def main():
    root = tk.Tk()
    rp = RestartableProgress(root)
    rp.pack()
    tk.mainloop()


if __name__ == '__main__':
    main()