将数学输出转换为canvas.create_tex

Question

我试图计算一个公式，并在TKinter中将其输出显示为一个表。因为它不起作用，所以我只想得到一个简单的结果并将它打印到一个canvas小部件上。当这一切开始运作时，我将完成整个贷款方案。实际上，我在GUI或控制台中没有输出。 是否可以将计算结果作为文本放入canvas.create_文本？在

from tkinter import * # Import tkinter

width = 500
height = 500

class MainGUI:
    def __init__(self):
        window = Tk() # Create a window
        window.title(" Loan Schedule ") # Set title

        frame1 = Frame(window)
        frame1.grid(row = 1, column = 1)

        Label(frame1, text = " Loan Amount ").grid(row = 1, column = 1, sticky = W)
        self.v1 = StringVar()
        Entry(frame1, textvariable = self.v1, justify = RIGHT).grid(row = 1, column = 2)

        Label(frame1, text = " Years ").grid(row = 1, column = 3, sticky = W)
        self.v2 = StringVar()
        Entry(frame1, textvariable = self.v2, justify = RIGHT).grid(row = 1, column = 4)

        btCalculate = Button(frame1, text = " Calculate ", command = self.calculate()).grid(row = 1, column = 5, sticky = E)

        frame2 = Frame(window)
        frame2.grid(row = 2, column = 1)

        self.canvas = Canvas(frame2, width = width, height = height, bg = "white")
        self.canvas.pack()

        self.canvas.create_text(25, 25, text = self.calculate(), tags = "text")       

        window.mainloop() # Create an event loop

    def calculate(self):
        result = self.v1.get() + self.v2.get()
        print(result)
        return result

MainGUI()

Answer 1

command需要不带（）的函数名

command = self.calculate

所以现在它起作用了

^{pr2}$

顺便说一下：下面的行意味着-run self.calculate()，结果赋值给command

command = self.calculate()