Question

我在tkinter中有一个OptionMenu。菜单中的选项是字典中的键。每个键的值是一个包含4个项目的列表。

如何使用所选菜单选项将4个项目分配给单独的变量？

from tkinter import *

root = Tk()

options = {'option 1' : ['list item 1' , 'list item 2' , 'list item 3' , 'list item 4'] , 'option 2' : ['list item w' , 'list item x' , 'list item y' , 'list item z']}

options = sorted(options)

var = StringVar(root)
var.set('Choose an option')

option = OptionMenu(root, var, *options)
option.pack()

selection = StringVar()

def changeOption(*args):
    newSelection = options[var.get()]
    selection.set(newSelection)

var.trace('w', changeOption)

variable1 = # if option 1 was selected from the menu then this variable would contain list item 1
variable2 = # if option 1 was selected from the menu then this variable would contain list item 2
variable3 = # if option 1 was selected from the menu then this variable would contain list item 3
variable4 = # if option 1 was selected from the menu then this variable would contain list item 4

root.mainloop()

Answer 1

您必须在功能change_option中执行此操作，而不是在主要部分中执行此操作。

主要部分仅创建窗口/ GUI并启动mainloop()。然后mainloop()控制所有内容 - 当您更改change_option中的选项时，它会执行函数OptionMenu。

您可以使用var.get()或command=发送的第一个参数获取密钥，然后您可以从字典中获取数据。

但您无法将sorted()分配给options，因为sorted()仅返回已排序键的列表，而您无法访问oryginal字典。

keys = sorted(options)

完整代码：

from tkinter import *

# --- functions ---

def change_option(*args):

    # selected element

    print('     args:', args)
    print('var.get():', var.get())

    # get list from dictionary `options`

    data = options[var.get()]
    data = options[args[0]]

    print('     data:', data[0], data[1], data[2], data[3])

    # if you really need in separated varaibles

    variable1 = data[0]
    variable2 = data[1]
    variable3 = data[2]
    variable4 = data[3]

    print('variables:', variable1, variable2, variable3, variable4)

    print('---')

# --- main ---

root = Tk()

options = {
    'option 1': ['list item 1', 'list item 2', 'list item 3', 'list item 4'],
    'option 2': ['list item w', 'list item x', 'list item y', 'list item z']
}

keys = sorted(options) # don't overwrite `options` - sorted() returns only keys from dictionary.

var = StringVar(root)
var.set('Choose an option')

option = OptionMenu(root, var, *keys, command=change_option)
option.pack()

root.mainloop()

结果：

     args: ('option 1',)
var.get(): option 1
     data: list item 1 list item 2 list item 3 list item 4
variables: list item 1 list item 2 list item 3 list item 4
---
     args: ('option 2',)
var.get(): option 2
     data: list item w list item x list item y list item z
variables: list item w list item x list item y list item z
---

Answer 2

您可以使用OptionMenu的command选项。每次从下拉列表中选择一个选项时，该命令都会执行。

from tkinter import *

root = Tk()

def change_vars(e):
    for i in range(len(options[var.get()])):
        vars[i].set(options[var.get()][i])

    #these two prints added for debugging purposes 
    #to see if we are getting and setting right values
    print(options[var.get()])    
    for item in vars:
        print(item.get())

options = {'option 1':['list item 1','list item 2','list item 3','list item 4'] , 'option 2':['list item w','list item x','list item y','list item z']}

var = StringVar(root)
var.set('Choose an option')

option = OptionMenu(root, var, *options, command=change_vars)
option.pack()
vars = [StringVar() for _ in range(len(options[0]))] #creates a list of 4 stringvars
root.mainloop()

在这里，我不是硬编码所有变量，而是在循环中创建它们并将它们存储在列表中。

在tkinter OptionMenu中访问字典值（字典值是列表）并存储在变量中

2 个答案: