如何使用列表框中的每个新选择更新 tkinter 标签？

Question

我希望在选择列表框中的名称时更新右侧的标签。选择列表中的新名称时，右侧的名称标签保持不变。

我直接在 student_name.set() 中尝试 name_list.index(ACTIVE) 为 student_name.set(students_list[name_list.index(ACTIVE)].get_name())。恐怕它只是使用索引 0，甚至没有使用主动选择。

from tkinter import *

# Defining Student class
class Student:

  def __init__(self, name, instrument=""):
    self.name = name
    self.instrument = instrument

  def get_name(self):
    return self.name

  def get_instrument(self):
    return self.instrument

# Creating Student objects and list
s1 = Student("Seth", "Trumpet")
s2 = Student("Cassie", "Flute")
s3 = Student("Cody", "Guitar")
students_list = [s1, s2, s3]

# GUI created
def make_window():
  rootWindow = Tk()
  rootWindow.title("Instructor Database Application")
  rootWindow.grid()

  frame0 = Frame(rootWindow)
  frame0.grid(column=0, row=0, padx=20, pady=20)

  name_list = Listbox(frame0, height=10)
  name_list.grid(column=0, row=0)
  for Student in students_list:
    name_list.insert(END, Student.get_name())

  frame1 = Frame(rootWindow)
  frame1.grid(column=1, row=0, padx=20, pady=20)

  student_index = name_list.index(ACTIVE)
  student_name = StringVar()
  student_name.set(students_list[student_index].get_name())

  name_label = Label(frame1, textvariable=student_name)
  name_label.grid(column=0, row=0)

  instrument_label = Label(frame1, text="Instrument")
  instrument_label.grid(column=0, row=1)

  return rootWindow

def main():
  app = make_window()
  app.mainloop()

main()

程序以名字开头，无法更改。有什么建议吗？

Answer 1

您必须将函数绑定到listbox，这将在您更改选择时执行。这个函数必须改变标签中的文本

listbox.bind('<<ListboxSelect>>', my_function)

---

最小的工作示例

import tkinter as tk

# --- function ---

def on_selection(event):
    # here you can get selected element
    print('previous:', listbox.get('active'))
    print(' current:', listbox.get(listbox.curselection()))

    # or using `event`

    #print('event:', event)
    #print('widget:', event.widget)
    print('(event) previous:', event.widget.get('active'))
    print('(event)  current:', event.widget.get(event.widget.curselection()))

    lbl['text'] = "Seleced: " + listbox.get(listbox.curselection())
    print('---')

# --- main ---

root = tk.Tk()

listbox = tk.Listbox(root)
listbox.pack()

listbox.insert(1, 'Hello 1')
listbox.insert(2, 'Hello 2')
listbox.insert(3, 'Hello 3')
listbox.insert(4, 'Hello 4')
listbox.bind('<<ListboxSelect>>', on_selection)

lbl = tk.Label(root, text='?')
lbl.pack()

root.mainloop()