在Python3/tkinter中，當用戶單擊Toplevel窗口上的關閉按鈕時如何攔截

Question

我想要一個主窗口和一個或多個可按需打開的Toplevel()窗口。我能夠創造窗戶甚至摧毀它們。我試圖在主窗口中實現一個按鈕，它既可以打開又可以關閉第二個窗口（第二個窗口應該始終是唯一的，即永遠不會同時打開兩次）。這是我現在，擺弄一點後：

#!/usr/bin/python3 

import tkinter as tk 
from tkinter import ttk 
import tkinter.font 


class baseApp(ttk.Frame): 
    def __init__(self,master,*args,**kwargs): 
     super().__init__(master,*args,**kwargs) 
     self.master = master 

     self.mainframe = ttk.Frame(master) 
     self.topframe = ttk.Frame(self.mainframe, padding="5 8 5 5") 

     self.topframe.pack(side=tk.TOP, fill=tk.X) 
     self.mainframe.pack(side=tk.TOP, expand=True, fill=tk.BOTH) 


class App(baseApp): 
    def __init__(self,master,*args,**kwargs): 
     super().__init__(master,*args,**kwargs) 
     self.master = master 
     self.button1 = ttk.Button(self.topframe,text="One",command=self.button_one) 
     self.btn_remessas = ttk.Button(self.topframe,text="Open/close Toplevel window",command=self.create_window1) 
     self.button1.grid(row=0,column=0) 
     self.btn_remessas.grid(row=0,column=1) 
     self.topframe.pack(side=tk.TOP, fill=tk.X) 
     self.mainframe.pack(side=tk.TOP, expand=True, fill=tk.BOTH) 

    def create_window1(self): 
     if current_state.window2_open == False: 
      self.newWindow2 = tk.Toplevel(self.master) 
      self.newWindow2.geometry('600x500+680+0') 
      self.newWindow2.title('Second window') 
      self.janela_remessas = SecondWindow(self.newWindow2) 
      current_state.window2_open = True    
     else: 
      self.newWindow2.destroy() 
      root.update_idletasks() 
      current_state.window2_open = False 

    def button_one(self): 
     print("button 1 pressed") 


class SecondWindow: 
    def __init__(self,master,*args,**kwargs): 
     #super().__init__(master,*args,**kwargs) 
     self.mainframe = ttk.Frame(master, padding="5 8 5 5") 
     self.topframe = ttk.Frame(self.mainframe) 
     self.button1 = ttk.Button(self.topframe,text="button",command=self.button_function) 
     self.button1.pack()     
     self.topframe.pack(side=tk.TOP, fill=tk.X) 
     self.mainframe.pack(side=tk.TOP, expand=True, fill=tk.BOTH) 

    def button_function(self, *event): 
     print("user just pressed button") 

    def close_window(self, *event): #Please fix me! 
     current_state.window2_open = False 
     self.destroy() 


class AppStatus: 
    def __init__(self): 
     self.window2_open = False 


if __name__ == "__main__": 
    root = tk.Tk() 
    app = App(root) 
    current_state = AppStatus() 
    root.configure(background='grey95') 
    root.title('Application window') 
    root.geometry('1000x760+0+0') 
    root.bind_all("<Mod2-q>", exit) 
    root.mainloop() 

現在，如果用戶點擊關閉窗口按鈕，或相應的鍵盤快捷鍵，應用程序將不知道第二個窗口已不存在，所以當我們按下按鈕打開/關閉窗口時，什麼都不會發生。另外，如果我們繼續按下打開/關閉按鈕，有時候按鈕不會打開第二個窗口。我究竟做錯了什麼？

Answer 1

您想要使用頂級窗口小部件的wm_protocol方法。具體與WM_DELETE_WINDOW協議。

>>> import tkinter as tk 
>>> root = tk.Tk() 
>>> dlg = tk.Toplevel(root) 
>>> dlg.wm_title("dialog") 
'' 
>>> root.wm_protocol("WM_DELETE_WINDOW", lambda: print("close root")) 
'' 
>>> dlg.wm_protocol("WM_DELETE_WINDOW", lambda: print("close dialog")) 
'' 
>>> root.mainloop() 
close dialog 
close root 

當我點擊窗口框關閉按鈕（大紅色X）時輸出最後一行。當我點擊這個時，現在不會退出，並且在任何一個Tk窗口上也要求Alt-F4。

Tk documentation有更多話要說。我發現的python文檔看起來很稀疏。

Answer 2

只要按照patthoyts的建議發佈完整的工作代碼。

#!/usr/bin/python3 

import tkinter as tk 
from tkinter import ttk 
import tkinter.font 


class baseApp(ttk.Frame): 
    def __init__(self,master,*args,**kwargs): 
     super().__init__(master,*args,**kwargs) 
     self.master = master 

     self.mainframe = ttk.Frame(master) 
     self.topframe = ttk.Frame(self.mainframe, padding="5 8 5 5") 

     self.topframe.pack(side=tk.TOP, fill=tk.X) 
     self.mainframe.pack(side=tk.TOP, expand=True, fill=tk.BOTH) 


class App(baseApp): 
    def __init__(self,master,*args,**kwargs): 
     super().__init__(master,*args,**kwargs) 
     self.master = master 
     self.button1 = ttk.Button(self.topframe,text="One",command=self.button_one) 
     self.btn_remessas = ttk.Button(self.topframe,text="Open/close Toplevel window",command=self.create_window2) 
     self.button1.grid(row=0,column=0) 
     self.btn_remessas.grid(row=0,column=1) 
     self.topframe.pack(side=tk.TOP, fill=tk.X) 
     self.mainframe.pack(side=tk.TOP, expand=True, fill=tk.BOTH) 

    def create_window2(self): 
     if current_state.window2_open == False: 
      self.newWindow2 = tk.Toplevel(self.master) 
      self.newWindow2.geometry('600x500+680+0') 
      self.newWindow2.title('Second window') 
      self.janela_remessas = SecondWindow(self.newWindow2) 
      current_state.window2_open = True 
      self.newWindow2.wm_protocol("WM_DELETE_WINDOW", lambda: self.close_window2())   
     else: 
      self.close_window2() 

    def close_window2(self, *event): 
     print("closing window") 
     root.update_idletasks() 
     current_state.window2_open = False 
     self.newWindow2.destroy() 

    def button_one(self): 
     print("button 1 pressed") 


class SecondWindow: 
    def __init__(self,master,*args,**kwargs): 
     #super().__init__(master,*args,**kwargs) 
     self.mainframe = ttk.Frame(master, padding="5 8 5 5") 
     self.topframe = ttk.Frame(self.mainframe) 
     self.button1 = ttk.Button(self.topframe,text="button",command=self.button_function) 
     self.button1.pack()     
     self.topframe.pack(side=tk.TOP, fill=tk.X) 
     self.mainframe.pack(side=tk.TOP, expand=True, fill=tk.BOTH) 

    def button_function(self, *event): 
     print("user just pressed button") 

    def close_window(self, *event): #Please fix me! 
     current_state.window2_open = False 
     self.destroy() 


class AppStatus: 
    def __init__(self): 
     self.window2_open = False 


if __name__ == "__main__": 
    root = tk.Tk() 
    app = App(root) 
    current_state = AppStatus() 
    root.configure(background='grey95') 
    root.title('Application window') 
    root.geometry('1000x760+0+0') 
    root.bind_all("<Mod2-q>", exit) 
    root.mainloop()