未显示自定义GUI元素的类

Question

我正在尝试创建一个GUI，如下图所示：

代码如下：

#! /usr/bin/python3

import tkinter as tk

# CLASS FOR OWN PANEL: 
class Mypanel(tk.Tk):
    def __init__(self):
        tk.Tk.__init__(self)
        self.label = tk.Label(self, text="Enter here:")
        self.entry = tk.Entry(self)
        self.label.pack()
        self.entry.pack()

# FN FOR BUTTON:
def adder():
    main_label.set((panel1.entry.get() + panel2.entry.get()))

# CREATE GUI ELEMENTS: 
main_window = tk.Tk()       # CREATE MAIN WINDOW
panel1 = Mypanel()          # CREATE A PANEL
panel2 = Mypanel()          # CREATE ANOTHER PANEL
main_label = tk.Label(main_window, text="Press button to get values.")  
main_button = tk.Button(main_window, text="Get values.", command=adder) 

# PACK ALL GUI ELEMENTS IN main WINDOW
panel1.pack()
panel2.pack()
main_label.pack()
main_button.pack()

# SHOW MAIN WINDOW: 
main_window.mainloop()

但是，它给出了以下错误：

$ ./guipanels.py
Traceback (most recent call last):
  File "./guipanels.py", line 29, in <module>
    panel1.pack()
  File "/usr/lib/python3.5/tkinter/__init__.py", line 1961, in __getattr__
    return getattr(self.tk, attr)
AttributeError: '_tkinter.tkapp' object has no attribute 'pack'

问题出在哪里，如何解决？谢谢你的帮助

Answer 1

您需要的不是Tk类而是Frame：

import tkinter as tk

# CLASS FOR OWN PANEL:
class Mypanel(tk.Frame):
    def __init__(self, master=None, **kwargs):
        super().__init__(master, kwargs)
        self.label = tk.Label(self, text="Enter here:")
        self.entry = tk.Entry(self)

        self.label.pack()
        self.entry.pack()
        # def on_button(self):
            # print(self.entry.get())

# FN FOR BUTTON:
def adder():
    main_label.set((panel1.entry.get() + panel2.entry.get()))

# CREATE GUI ELEMENTS:
main_window = tk.Tk()       # CREATE MAIN WINDOW
panel1 = Mypanel(main_window)          # CREATE A PANEL
panel2 = Mypanel(main_window)          # CREATE ANOTHER PANEL
main_label = tk.Label(main_window, text="Press button to get values.")
main_button = tk.Button(main_window, text="Get values.", command=adder)

# PACK ALL GUI ELEMENTS IN main WINDOW
panel1.pack()
panel2.pack()
main_label.pack()
main_button.pack()

# SHOW MAIN WINDOW:
main_window.mainloop()

您可以将类Tk视为主应用程序，并将小部件放在其中。一个代码中应该只有一个Tk

Answer 2

你的意思是把tk.PanedWindow子类化吗

试试这个：

class Mypanel(tk.PanedWindow):
    def __init__(self, mainwindow):
        super(Mypanel, self).__init__(mainwindow)
        self.label = tk.Label(self, text="Enter here:")
        self.entry = tk.Entry(self)

        self.label.pack()
        self.entry.pack()
        # def on_button(self):
            # print(self.entry.get())

并将代码中的main_window传递给面板：

main_window = tk.Tk()       # CREATE MAIN WINDOW
panel1 = Mypanel(main_window)          # CREATE A PANEL
panel2 = Mypanel(main_window)          # CREATE ANOTHER PANEL