如何使用Python中的tkinter使用GUI编程计算器？

我正在为GCSE进行计算,我们的控制评估的任务之一是创建一个带有GUI的计算器.

我能够在没有GUI的情况下编写一个简单的计算器,但我不知道如何用GUI完成它.

下面是我从teampython.wordpress.com获得的代码,我模糊地理解,但如果有人可以向我解释每个步骤,那将会非常有用.

 # calc.py - a Python calculator
 from tkinter import *


class Calc():
    def __init__(self):
        self.total = 0
        self.current = ""
        self.new_num = True
        self.op_pending = False
        self.op = ""
        self.eq = False


    def num_press(self, num):
        self.eq = False
        temp = text_box.get()
        temp2 = str(num)      
        if self.new_num:
            self.current = temp2
            self.new_num = False
        else:
            if temp2 == '.':
                if temp2 in temp:
                    return
            self.current = temp + temp2
        self.display(self.current)

    def calc_total(self):
        self.eq = True
        self.current = float(self.current)
        if self.op_pending == True:
            self.do_sum()
        else:
            self.total = float(text_box.get())

    def display(self, value):
        text_box.delete(0, END)
        text_box.insert(0, value)

    def do_sum(self):
        if self.op == "add":
            self.total += self.current
        if self.op == "minus":
            self.total -= self.current
        if self.op == "times":
            self.total *= self.current
        if self.op == "divide":
            self.total /= self.current
        self.new_num = True
        self.op_pending = False
        self.display(self.total)

    def operation(self, op): 
        self.current = float(self.current)
        if self.op_pending:
            self.do_sum()
        elif not self.eq:
            self.total = self.current
        self.new_num = True
        self.op_pending = True
        self.op = op
        self.eq = False

    def cancel(self):
        self.eq = False
        self.current = "0"
        self.display(0)
        self.new_num = True

    def all_cancel(self):
        self.cancel()
        self.total = 0

    def sign(self):
        self.eq = False
        self.current = -(float(text_box.get()))
        self.display(self.current)

sum1 = Calc()
root = Tk()
calc = Frame(root)
calc.grid()

root.title("Calculator")
text_box = Entry(calc, justify=RIGHT)
text_box.grid(row = 0, column = 0, columnspan = 3, pady = 5)
text_box.insert(0, "0")

numbers = "789456123"
i = 0
bttn = []
for j in range(1,4):
    for k in range(3):
        bttn.append(Button(calc, text = numbers[i]))
        bttn[i].grid(row = j, column = k, pady = 5)
        bttn[i]["command"] = lambda x = numbers[i]: sum1.num_press(x)
        i += 1

bttn_0 = Button(calc, text = "0")
bttn_0["command"] = lambda: sum1.num_press(0)
bttn_0.grid(row = 4, column = 1, pady = 5)

bttn_div = Button(calc, text = chr(247))
bttn_div["command"] = lambda: sum1.operation("divide")
bttn_div.grid(row = 1, column = 3, pady = 5)

bttn_mult = Button(calc, text = "x")
bttn_mult["command"] = lambda: sum1.operation("times")
bttn_mult.grid(row = 2, column = 3, pady = 5)

minus = Button(calc, text = "-")
minus["command"] = lambda: sum1.operation("minus")
minus.grid(row = 3, column = 3, pady = 5)

point = Button(calc, text = ".")
point["command"] = lambda: sum1.num_press(".")
point.grid(row = 4, column = 0, pady = 5)

add = Button(calc, text = "+")
add["command"] = lambda: sum1.operation("add")
add.grid(row = 4, column = 3, pady = 5)

neg= Button(calc, text = "+/-")
neg["command"] = sum1.sign
neg.grid(row = 5, column = 0, pady = 5)

clear = Button(calc, text = "C")
clear["command"] = sum1.cancel
clear.grid(row = 5, column = 1, pady = 5)

all_clear = Button(calc, text = "AC")
all_clear["command"] = sum1.all_cancel
all_clear.grid(row = 5, column = 2, pady = 5)

equals = Button(calc, text = "=")
equals["command"] = sum1.calc_total
equals.grid(row = 5, column = 3, pady = 5)

root.mainloop()

MarkyD43.. 10

所以,我会解释你给我最好的代码.该类Calc()包含此段代码的所有函数.结构意味着主GUI(稍后设置)可以轻松访问每个功能.在Calc()课堂上,你有你的功能(用def等等表示).它们包含此代码计算其输出的各种方法.

在课堂之外,我们有Tkinter UI代码.此代码构建您的窗口,其中包含各种按钮和显示.在这种情况下,按钮和文本字段的位置由"网格"方法控制.正如你所看到的,每一次的代码设置了一个对象(这里只Frame,Button和Entry对象),存在相关联.grid(row=x, column=y...etc).这指定了UI中每个对象的相对位置.例如,使用网格方法,您可以通过给出第一个对象row = 1,column = 0和第二行= 2,column = 0等来堆叠两个对象.

for循环:

for j in range(1,4):
    for k in range(3):
        bttn.append(Button(calc, text = numbers[i]))
        bttn[i].grid(row = j, column = k, pady = 5)
        bttn[i]["command"] = lambda x = numbers[i]: sum1.num_press(x)
        i += 1 

可能是用户界面的唯一部分,如果你刚刚开始,就不容易看到.从本质上讲,它所做的就是自动构建按钮(节省您单独编写每个按钮的时间).循环中的前两行(希望)明显地循环指定范围内的值.在该行之下,该行在bttn.append(...之前设置的calc框架中创建一个按钮对象calc = Frame(root),按钮文本由数字列表给出(字面意思numbers="789456123"如上).最初,i = 0,因此numbers [i]将返回列表编号中的第一个元素,i = 1的数字[i](下次循环时)将给出8,依此类推.在bttn.grid(row = j, column = k, pady = 5)使用前面提到的格定位方法,但这里的j和k是通过在环本身(的值给定的行的情况下,值1和4之间的值,且0和2之间- 3列-在的情况下列).如果您运行代码,您可以看到这将定位所有键盘按钮以输入数字.此循环中的最后一行(除了i + = 1,即向i添加1),处理为按钮分配命令.该命令将调用一个相关的函数,在本例中是numpress函数in Calc().正如您可能看到的那样,numpress本身会根据您按下的数字更新您的显示器.

此示例中的最后一个代码块处理计算器的其余操作,您会注意到每个操作都遵循上面创建按钮的模式,分配命令并在UI中定位按钮.根据我上面已经解释过的,您可能会看到每个剩余的函数都Calc()支配算术运算,或清除等.

我意识到这是一面文字,但我希望它有所帮助!如果我一直不清楚或有什么特别的你不理解,请告诉我,我会尝试解释它(我不久就学会了自己!).

您可能会发现此Tkinter UI指南很有用,我从该指南中学到了很多基础知识.

祝好运