如何在Python中制作更多的Tkinter按钮

Question

I am making a PC helper program with a gui for a school project. I have added two buttons but I cant seem to add more than two...

Here is the code:

#All imports go here
import tkinter as tk
import os

class Application(tk.Frame):
    def __init__(self, master=None):
        super().__init__(master)
        self.pack()
        self.create_widgets()

    def create_widgets(self):
        self.hi_there = tk.Button(self)
        self.hi_there["text"] = "Hello, what would you like help with today?"
        self.hi_there["command"] = self.say_hi
        self.hi_there.pack(side="top")

    def create_widgets(self):
        self.notepad = tk.Button(self)
        self.notepad["text"] = "Launch Notepad"
        self.notepad["command"] = self.notepad
        self.notepad.pack(side="right")

    def create_widgets(self):
        self.hi = tk.Button(self)
        self.hi["text"] = "Launch CMD"
        self.hi["command"] = self.cmd
        self.hi.pack(side="left") 

        self.quit = tk.Button(self, text="QUIT", fg="red",
                          command=root.destroy)
        self.quit.pack(side="bottom")

    def cmd(self):
        os.system("start cmd /a")

    def notepad(self):
        os.system("start notepad")

root = tk.Tk()
app = Application(master=root)
app.mainloop()

sys.exit()

Answer 1

Two created buttons are definded here:

def create_widgets(self):
    self.hi = tk.Button(self)
    self.hi["text"] = "Launch CMD"
    self.hi["command"] = self.cmd
    self.hi.pack(side="left")

    self.quit = tk.Button(self, text="QUIT", fg="red",
                      command=root.destroy)
    self.quit.pack(side="bottom")

But why only these are created? Answer is simple, look comments in code below:

class Application(tk.Frame):
    def __init__(self, master=None):
        super().__init__(master)
        self.pack()
        self.create_widgets()
        self.create_widgets2()
        self.create_widgets3()

    def create_widgets(self):  # define
        self.hi_there = tk.Button(self)
        self.hi_there["text"] = "Hello, what would you like help with today?"
        self.hi_there["command"] = self.say_hi  # additional bug (AttributeError: 'Application' object has no attribute 'say_hi'), change this to "self.hi_there["command"] = self.hi_there"
        self.hi_there.pack(side="top")

    def create_widgets(self):  # re-define without usage
        self.notepad = tk.Button(self)
        self.notepad["text"] = "Launch Notepad"
        self.notepad["command"] = self.notepad
        self.notepad.pack(side="right")

    def create_widgets(self):  # again re-define without usage
        self.hi = tk.Button(self)
        self.hi["text"] = "Launch CMD"
        self.hi["command"] = self.cmd
        self.hi.pack(side="left")

        self.quit = tk.Button(self, text="QUIT", fg="red", command=root.destroy)
        self.quit.pack(side="bottom")

    def cmd(self):
        os.system("start cmd /a")

    def notepad(self):
        os.system("start notepad")

This code gives the same efect as code below.

class Application(tk.Frame):
def __init__(self, master=None):
    super().__init__(master)
    self.pack()
    self.create_widgets()

def create_widgets(self):
    self.hi = tk.Button(self)
    self.hi["text"] = "Launch CMD"
    self.hi["command"] = self.cmd
    self.hi.pack(side="left")

    self.quit = tk.Button(self, text="QUIT", fg="red",
                      command=root.destroy)
    self.quit.pack(side="bottom")

def cmd(self):
    os.system("start cmd /a")

def notepad(self):
    os.system("start notepad")

Defining functions is similar to assigning the variable value:

a = 1
a = 4
a = 150
print(a)  # will print 150, not 1, 4, 150

So you should put all the buttons (other widgets in future too) in the same function or change the function names and call them in the init function.

Working code (first way, better in my opinion):

import tkinter as tk
import os


class Application(tk.Frame):
    def __init__(self, master=None):
        super().__init__(master)
        self.pack()
        self.create_widgets()

    def create_widgets(self):
        self.hi_there = tk.Button(self)
        self.hi_there["text"] = "Hello, what would you like help with today?"
        self.hi_there["command"] = self.hi_there
        self.hi_there.pack(side="top")

        self.notepad = tk.Button(self)
        self.notepad["text"] = "Launch Notepad"
        self.notepad["command"] = self.notepad
        self.notepad.pack(side="right")

        self.hi = tk.Button(self)
        self.hi["text"] = "Launch CMD"
        self.hi["command"] = self.cmd
        self.hi.pack(side="left")

        self.quit = tk.Button(self, text="QUIT", fg="red", command=root.destroy)
        self.quit.pack(side="bottom")

    def cmd(self):
        os.system("start cmd /a")

    def notepad(self):
        os.system("start notepad")


root = tk.Tk()
app = Application(master=root)
app.mainloop()
sys.exit()

Second way:

import tkinter as tk
import os


class Application(tk.Frame):
    def __init__(self, master=None):
        super().__init__(master)
        self.pack()
        self.create_widgets()
        self.create_widgets2()
        self.create_widgets3()

    def create_widgets(self):
        self.hi_there = tk.Button(self)
        self.hi_there["text"] = "Hello, what would you like help with today?"
        self.hi_there["command"] = self.hi_there
        self.hi_there.pack(side="top")

    def create_widgets2(self):
        self.notepad = tk.Button(self)
        self.notepad["text"] = "Launch Notepad"
        self.notepad["command"] = self.notepad
        self.notepad.pack(side="right")

    def create_widgets3(self):
        self.hi = tk.Button(self)
        self.hi["text"] = "Launch CMD"
        self.hi["command"] = self.cmd
        self.hi.pack(side="left")

        self.quit = tk.Button(self, text="QUIT", fg="red", command=root.destroy)
        self.quit.pack(side="bottom")

    def cmd(self):
        os.system("start cmd /a")

    def notepad(self):
        os.system("start notepad")


root = tk.Tk()
app = Application(master=root)
app.mainloop()
sys.exit()

I apologize for any language mistakes, but English is not my native language.