三、hello world 2!

# 用类封装后的hello world

from tkinter import *

# 定义类
class App:
    def __init__(self,master):

        # 创建一个Frame用于包含其他widget
        frame = Frame(master)
        frame.pack()

        # 创建一个Button
        self.button = Button(frame, # master widget
                text="QUIT", fg="red", command=frame.quit)
        self.button.pack(side=LEFT)

        self.hi_there = Button(frame, text="Hello",command=self.say_hi)
        self.hi_there.pack(side=LEFT)

    def say_hi(self):
        print("hi there,everyone!")

root = Tk()
app = App(root)
root.mainloop()