Python Tkinter GUI 计算器

Question

所以我目前正在制作一个 GUI 计算器，但不确定如何编写代码来执行计算器的操作。现在我已经设置了窗口、输入框和计算器按钮，但目前它们都没有真正做任何事情。

我只是对这些按钮在代码中的表示方式感到困惑，所以我不知道如何编写一个能够读取这些按钮输入并执行加法、减法等的代码块。

这是我目前的代码

class Calculator(Frame):
def __init__(self,master):
    Frame.__init__(self,master)
    self.grid()

    self.dataEnt = Entry(self)
    self.dataEnt.grid(row = 0, column = 1, columnspan = 4)

    labels =[['AC','%','/'],
         ['7','8','9','*'],
         ['4','5','6','-'],
         ['1','2','3','+'],
         ['0','.','=']]
    label = Button(self,relief = RAISED, padx = 10, text = labels[0][0]) #AC
    label.grid(row = 1, column = 0, columnspan = 2)
    label = Button(self,relief = RAISED, padx = 10, text = labels[0][1]) # %
    label.grid(row = 1, column = 3)
    label = Button(self,relief = RAISED, padx = 10, text = labels[0][2]) # /
    label.grid(row = 1, column = 4)
    for r in range(1,4):
        for c in range(4):
            #create label for row r and column c 
            label = Button(self,relief = RAISED,
                          padx = 10,
                          text = labels[r][c]) # 789* 456- 123+ 
            # place label in row r and column c
            label.grid(row = r+1, column = c+1)

    label = Button(self,relief = RAISED, padx = 10, text = labels[4][0]) #0
    label.grid(row = 5, column = 0, columnspan = 2)
    label = Button(self,relief = RAISED, padx = 10, text = labels[4][1]) # .
    label.grid(row = 5, column = 3)
    label = Button(self,relief = RAISED, padx = 10, text = labels[4][2]) # =
    label.grid(row = 5, column = 4)

  def operations(self,num ):

def main():
    root = Tk()
    root.title('Calculator')
    obj = Calculator(root)
    root.mainloop()            

and here is what the calculator looks like so far

我的猜测是，我需要以某种方式将输入读取为字符串，然后让 python 将该字符串评估为数学表达式，但我不知道该怎么做。

感谢您的帮助！

Answer 1

您可以做的是将所有按钮绑定到一个方法，该方法识别按钮并将字符串附加到列表或评估表达式。然后可以在标签中显示此列表。

def button_press(self, event):
    widget = event.widget
    text = widget["text"]
    if text != "AC" and text != "=":
        self.operations.append(text)
    elif text == "AC":
        self.operations = []  # Clear the list.
    elif text == "=":
        self.evaluate()
    self.label["text"] = "".join(self.operations)

def evaluate(self):
    try:
        self.operations = [str(eval("".join(self.operations)))]
    except (ArithmeticError, SyntaxError, TypeError, NameError):
        self.operations = ["ERROR"]

此代码不能只是粘贴到您的程序中，它只是为了演示如何解决问题。

Answer 2

简单地使用 pyautogui 作为基本的 GUI 计算器

import math
import pyautogui
print( '+ =add |- =subtraction |* =multiplication | / =division |w =remainder of division |i =percentage |s =product of a number by itself \n'
        '|p =prime number |r =square root')
def p(num):
    for i in range(2, int(num)):
        if int(num) % i == 0:
            return i
    return False
while True:
    try:
        try:
            #----------------------------------------------------------#
            num=float(pyautogui.prompt('1st','pcalculator'))
            op=pyautogui.prompt('sign','pcalculator')
            if not op == 'p':
                nun=float(pyautogui.prompt('2nd','pcalculator'))
            if op=='+':
            x=pyautogui.confirm(num+nun,'pcalculator ',buttons=['Ok','Cancel'])
            if x=='Cancel':
                break
            elif op=='-':
                x=pyautogui.confirm(num-nun,'pcalculator ',buttons=['Ok','Cancel'])
                if x=='Cancel':
                break
            elif op=='*':
                x=pyautogui.confirm(num*nun,'pcalculator ',buttons=['Ok','Cancel'])
                if x=='Cancel':
                break
            elif op=='/':
                x=pyautogui.confirm(num/nun,'pcalculator ',buttons=['Ok','Cancel'])
                if x=='Cancel':
                break
            elif op=='w':
                x=pyautogui.confirm(num%nun,'pcalculator ',buttons=['Ok','Cancel'])
                if x=='Cancel':
                break
            elif op=='i':
                x=pyautogui.confirm(num/nun*100,'pcalculator ',buttons=['Ok','Cancel'])
                if x=='Cancel':
                break
            elif op=='s':
                x=pyautogui.confirm(num**nun,'pcalculator ',buttons=['Ok','Cancel'])
                if x=='Cancel':
                break            
            elif op=='p':
                if p(num):
                    x=pyautogui.confirm((int(num),'is a composite number'),'pcalculator',buttons=['Ok','Cancel'])
                    if x=='Cancel':
                        break
                else:
                    x=pyautogui.confirm((int(num),'is a prime number'),'pcalculator ',buttons=['Ok','Cancel'])
                    if x=='Cancel':
                        break
            elif op=='r':
                x=pyautogui.confirm(math.sqrt(num),'pcalculator ',buttons=['Ok','Cancel'])
                if x=='Cancel':
                    break
    #-------------------------------------------------------------------#
        except ZeroDivisionError:
                x=pyautogui.confirm("Error: you can not divide by 0",'pcalculator ',buttons=['Ok','Cancel'])
                if x=='Cancel':
                    break
    except ValueError:
        x=pyautogui.confirm('Invalid input,use only integers,decimals and symbols.','pcalculator ',buttons=['Ok','Cancel'])
        if x=='Cancel':
            break