在Tkinter Combobox中如何获取所选选项的索引？

Question

以下代码可以让我打印出从组合框中选择的值，但我需要打印（获取）所选项目在列表中的索引号。请告诉我如何做到这一点？

import Tkinter
import tkMessageBox
from Tkinter import *
import ttk
from ttk import *

app = Tk()

def OptionCallBack(*args):
    print variable.get()

variable = StringVar(app)
variable.set("Select From List")
variable.trace('w', OptionCallBack)

so = ttk.Combobox(app, textvariable=variable)
so.config(values =('Tracing Upstream', 'Tracing Downstream','Find Path'))
so.grid(row=1, column=4, sticky='E', padx=10)


app.mainloop()

- Behseini

Answer 1

在组合框上使用current方法。

import Tkinter
import tkMessageBox
from Tkinter import *
import ttk
from ttk import *

app = Tk()

def OptionCallBack(*args):
    print variable.get()
    print so.current()

variable = StringVar(app)
variable.set("Select From List")
variable.trace('w', OptionCallBack)


so = ttk.Combobox(app, textvariable=variable)
so.config(values =('Tracing Upstream', 'Tracing Downstream','Find Path'))
so.grid(row=1, column=4, sticky='E', padx=10)


app.mainloop()

- Khristos

Answer 2

如果你将bind()和current()结合起来，就可以实现。以下是一个快速演示：

import Tkinter
import tkMessageBox
from Tkinter import *
import ttk
from ttk import *

app = Tk()

def display_selected_item_index(event): 
   global so
   print 'index of this item is: {}\n'.format(so.current())

def OptionCallBack(*args):
    print variable.get()

variable = StringVar(app)
variable.set("Select From List")
variable.trace('w', OptionCallBack)

so = ttk.Combobox(app, textvariable=variable)
so.config(values =('Tracing Upstream', 'Tracing Downstream','Find Path'))
so.grid(row=1, column=4, sticky='E', padx=10)    
so.bind("<<ComboboxSelected>>", display_selected_item_index)  

app.mainloop()

- Billal Begueradj