Tkinter鍵綁定在消息框後不工作

Question

我正在使用計算器，並且遇到了有關我的鍵綁定的問題。在我的GUI類的啓動結束時，會創建一個消息框來解釋對用戶的綁定。具有諷刺意味的是，這會導致所有綁定在消息框關閉之前不作出響應，並且tkinter窗口被取消選擇然後重新選擇。綁定編碼是這樣的：

master.bind('<Delete>', self.delete) 
master.bind('<BackSpace>', self.back) 
master.bind('<Return>', self.equals) 
master.bind('<Insert>', self.add_answer) 

我試圖使用focus_set（）但它沒有幫助。消息框關閉後，我能做些什麼來使鍵盤綁定立即響應？

這是我的上下文的完整代碼。

from tkinter import * 
from tkinter.ttk import * 
from tkinter import messagebox # added by @martineau 

class Logic: 
    def add_digit(self, *args): 
     if type(args[0]) == str: 
      self.expression.append(args[0]) 
     else: 
      self.expression.append(args[0].char) 
     self.labels[1].config(text="".join(self.expression)) 

    def add_operation(self, *args): 
     if type(args[0]) == str: 
      self.expression.append(args[0]) 
     else: 
      self.expression.append(args[0].char) 
     self.labels[1].config(text="".join(self.expression)) 

    def add_answer(self, *args): 
     self.expression.extend(list(self.labels[0]['text'])) 
     self.labels[1].config(text="".join(self.expression)) 

    def delete(self, *args): 
     if self.expression: 
      self.expression = list() 
      self.labels[1].config(text="".join(self.expression)) 
     else: 
      self.labels[0].config(text="") 

    def back(self, *args): 
     self.expression = self.expression[:-1] 
     self.labels[1].config(text="".join(self.expression)) 

    def equals(self, *args): 
     equation = list() 
     number = list() 

     if not self.expression: 
      self.labels[0].config(text='') 

     for value in self.expression: 
      if value in self.numpad_texts: 
       number.append(value) 
      else: 
       if number: 
        equation.append(str(float("".join(number)))) 
        number = list() 
       equation.append(value) 

     if number: 
      try: 
       equation.append(str(float("".join(number)))) 
      except ValueError: 
       messagebox.showerror("Error", "Syntax error: Your expression has incorrect syntax") 

     for i in range(len(equation)): 
      if equation[i] == '(' and i != 0: 
       if equation[i-1] not in self.operation_texts: 
        equation.insert(i, '*') 
      elif equation[i] == ')' and i != len(equation)-1: 
       if equation[i+1] not in self.operation_texts: 
        equation.insert(i+1, '*') 

     if equation: 
      try: 
       self.labels[0].config(text=str(eval(''.join(equation)))) 
      except ZeroDivisionError: 
       messagebox.showerror("Error", "Zero division error: Your expression has a division by zero") 
      except SyntaxError: 
       messagebox.showerror("Error", "Syntax error: Your expression has incorrect syntax") 

class GUI(Logic): 
    numpad_texts = ('7', '8', '9', '4', '5', '6', '1', '2', '3', '0', '.', 'Equals') 
    operation_texts = ('/', '*', '-', '+', '(', ')') 
    function_texts = ('Delete', 'Back') 

    def __init__(self, master): 
     master.title('Calculator') 

     self.expression = list() 

     self.label_frame = Frame(master) 
     self.label_frame.grid(columnspan=2) 

     self.labels = list() 

     for i in range(2): 
      self.labels.append(Label(self.label_frame)) 
      self.labels[i].grid(row=i, column=0, columnspan=4) 

     self.labels[0].bind("<Button-1>", self.add_answer) 

     self.numpad_frame = Frame(master) 
     self.numpad_frame.grid(row=1, rowspan=2) 

     self.numpad_buttons = list() 

     for i in range(len(self.numpad_texts)): 
      self.numpad_buttons.append(Button(self.numpad_frame, text=self.numpad_texts[i], command=lambda i=i: self.add_digit(self.numpad_texts[i]))) 
      self.numpad_buttons[i].grid(row=i//3, column=i%3) 
      if self.numpad_texts != 11: 
       master.bind(self.numpad_texts[i], self.add_digit) 

     self.numpad_buttons[-1].config(command=self.equals) 

     self.operations_frame = Frame(master) 
     self.operations_frame.grid(row=1, column=1) 

     self.operation_buttons = list() 

     for i in range(len(self.operation_texts)): 
      self.operation_buttons.append(Button(self.operations_frame, text=self.operation_texts[i], command=lambda i=i: self.add_operation(self.operation_texts[i]))) 
      self.operation_buttons[i].grid(row=i//2, column=i%2) 
      master.bind(self.operation_texts[i], self.add_operation) 

     self.functions_frame = Frame(master) 
     self.functions_frame.grid(row=2, column=1) 

     self.function_buttons = list() 

     for i in range(len(self.function_texts)): 
      self.function_buttons.append(Button(self.functions_frame, text=self.function_texts[i])) 
      self.function_buttons[i].grid(row = 0, column=i%2) 

     self.function_buttons[0].config(command=self.delete) 
     self.function_buttons[1].config(command=self.back) 

     master.bind('<Delete>', self.delete) 
     master.bind('<BackSpace>', self.back) 
     master.bind('<Return>', self.equals) 
     master.bind('<Insert>', self.add_answer) 

     messagebox.showinfo("Guide", "Key bindings include: 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, ., +, -, *, /, (,), Enter, Backspace, Insert and Delete.") 

if __name__ == '__main__': 
    root = Tk() 
    calculator = GUI(root) 
    root.mainloop() 

Answer 1

Tkinters消息框需要分別輸入：

from tkinter import messagebox

然後添加以下爲您的綁定信息框的下面那條線：

master.focus_force()

這將焦點移至在用戶關閉消息箱和所有綁定之後回到根窗口將繼續工作。