如何在 Tkinter 中刷新我的程序？

Question

from Tkinter import *
from cmath import sqrt

window = Tk()
solution = "Nothing to see for now ~"
a = Entry(window)
a.pack()
b = Entry(window)
b.pack()
c = Entry(window)
c.pack()

result_text = Text(window)
result_text.pack()
def calculate():
    na = int(a.get())
    nb = int(b.get())
    nc = int(c.get())
    delta = (nb **2) - (4 * na * nc )
    if delta > 0:
        x1 = ((- nb) + sqrt(delta)) / (2 * na)
        x2 = ((- nb) - sqrt(delta)) / (2 * na)
        solution = "x1 = " + str(x1) + "\n x2 = " + str(x2)
        return  solution
    elif delta==0:
        x = (-nb) / (2 * na)
        solution = "x1 = " + str(x)
        return solution
    else:
        solution = "There isn't any solution for this equation."
        return solution

button = Button(window , text = "Calculate" , command = calculate)
button.pack()
result_text.insert(END,solution)
mainloop()

顺便说一句，我仍然是一个初学者......所以基本上我想做的是用 Tkinter 编写一个简单的 GUI 来计算二次方程的解，用户只需给出 a、b 和 c等式和程序在单击“计算”按钮后在文本小部件中显示结果，我做得很好，但它仍然不想用结果刷新文本小部件，而不是“暂时看不到任何东西” ~”消息！请问我该怎么办？

Answer 1

返回 solution 不会做任何事情，因为 Tkinter 只是丢弃了函数的结果。您需要从calculate 中更新结果文本。

def calculate():
    na = int(a.get())
    nb = int(b.get())
    nc = int(c.get())
    delta = (nb **2) - (4 * na * nc )
    if delta > 0:
        x1 = ((- nb) + sqrt(delta)) / (2 * na)
        x2 = ((- nb) - sqrt(delta)) / (2 * na)
        solution = "x1 = " + str(x1) + "\n x2 = " + str(x2)
    elif delta==0:
        x = (-nb) / (2 * na)
        solution = "x1 = " + str(x1) + "\n x2 = " + str(x2)
    else:
        solution = "There isn't any solution for this equation."
    result_text.delete("1.0", END)
    result_text.insert(END, solution)