无法使用 tkinter 使功能与检查按钮一起使用

Question

我不确定为什么这不起作用，我已经尝试更改事物的顺序，但它仍然不起作用。代码的重点是显示 Null 一词，当您选择任何复选按钮时，根据它的奇数还是偶数，它会将 Null 一词更改为奇数或偶数。任何帮助都会很好。

# Create a window
the_window = Tk()

# Give the window a title
the_window.title('Odd or Even')


##Some global variables
margin = 8
text = 'Null'

##Changing the size of the window
the_window.geometry("350x150")

##Making the label frame
labelframe = LabelFrame(the_window, bd = 3)
labelframe.grid(columnspan = 3, padx = margin, pady = margin)

##Adding the Label
changeable_label = Label(labelframe, text = text, font = ('Arial', 60),
                           fg = ('black'))
changeable_label.pack(side = TOP)

##Addind the Check Buttons

def odd_even():
    chk_btn_value = value1 + value2 + value3

    if chk_btn_value == 0:
        text = 'Null'
    elif chk_btn_value % 2 != 0:
        text = 'Odd'    
    else:
        text = 'Even'

var1 = IntVar()
var2 = IntVar()
var3 = IntVar()

value1 = var1.get()
value2 = var2.get()
value3 = var3.get()


alpha = Checkbutton(the_window, text = 'Alpha', variable = var1,
                    onvalue = 1, offvalue = 0, command = odd_even)
alpha.grid(row = 1, column = 1)

beta = Checkbutton(the_window, text = 'Beta', variable = var2,
                    onvalue = 1, offvalue = 0, command = odd_even)
beta.grid(row = 1, column = 2)

gamma = Checkbutton(the_window, text = 'Gamma', variable = var3,
                    onvalue = 1, offvalue = 0, command = odd_even)
gamma.grid(row = 1, column = 3)


# Start the event loop
the_window.mainloop()

Answer 1

每次调用函数时都需要获取它们的值，因为每次选中或取消选中时它们都会发生变化。同样要更新标签的文本，您需要使用类似的东西。 label_name["text"] = "new_text"

除此之外，Checkbutton 的默认开启和关闭值分别为 1 和 0。你不需要写那些。

将所有这些应用到您的代码中，将会产生这样的结果。

from Tkinter import *

def odd_even():
    value1 = var1.get()
    value2 = var2.get()
    value3 = var3.get()
    chk_btn_value = value1 + value2 + value3

    if chk_btn_value == 0:
        changeable_label['text'] = "Null"
    elif chk_btn_value % 2 != 0:
        changeable_label['text'] = "Odd"
    else:
        changeable_label['text'] = "Even"

# Create a window
the_window = Tk()

# Give the window a title
the_window.title('Odd or Even')


##Some global variables
margin = 8
text = 'Null'

##Changing the size of the window
the_window.geometry("350x150")

##Making the label frame
labelframe = LabelFrame(the_window, bd = 3)
labelframe.grid(columnspan = 3, padx = margin, pady = margin)

##Adding the Label
changeable_label = Label(labelframe, text = text, font = ('Arial', 60),
                           fg = ('black'))
changeable_label.pack(side = TOP)

##Addind the Check Buttons

var1 = IntVar()
var2 = IntVar()
var3 = IntVar()

alpha = Checkbutton(the_window, text = 'Alpha', variable = var1,
                     command = odd_even)
alpha.grid(row = 1, column = 1)

beta = Checkbutton(the_window, text = 'Beta', variable = var2,
                     command = odd_even)
beta.grid(row = 1, column = 2)

gamma = Checkbutton(the_window, text = 'Gamma', variable = var3,
                     command = odd_even)
gamma.grid(row = 1, column = 3)


# Start the event loop
the_window.mainloop()

Answer 2

你必须在回调函数中调用 .get() 方法。还可以尝试 changeable_label.set("New Text!") 来更改标签的文本。 Effbot 有非常好的 tkinter 资源：http://effbot.org/tkinterbook/label.htm

from Tkinter import *
# Create a window
the_window = Tk()

# Give the window a title
the_window.title('Odd or Even')


##Some global variables
margin = 8
text = 'Null'

##Changing the size of the window
the_window.geometry("350x150")

##Making the label frame
labelframe = LabelFrame(the_window, bd = 3)
labelframe.grid(columnspan = 3, padx = margin, pady = margin)

##Adding the Label
changeable_label = Label(labelframe, text = text, font = ('Arial', 60),
                           fg = ('black'))
changeable_label.pack(side = TOP)

##Addind the Check Buttons

def odd_even():
    value1 = var1.get()
    value2 = var2.get()
    value3 = var3.get()
    chk_btn_value = value1 + value2 + value3
    print chk_btn_value

    if chk_btn_value == 0:
        text = 'Null'
    elif chk_btn_value % 2 != 0:
        text = 'Odd'    
    else:
        text = 'Even'

var1 = IntVar()
var2 = IntVar()
var3 = IntVar()




alpha = Checkbutton(the_window, text = 'Alpha', variable = var1,
                    onvalue = 1, offvalue = 0, command = odd_even)
alpha.grid(row = 1, column = 1)

beta = Checkbutton(the_window, text = 'Beta', variable = var2,
                    onvalue = 1, offvalue = 0, command = odd_even)
beta.grid(row = 1, column = 2)

gamma = Checkbutton(the_window, text = 'Gamma', variable = var3,
                    onvalue = 1, offvalue = 0, command = odd_even)
gamma.grid(row = 1, column = 3)


# Start the event loop
the_window.mainloop()