图形窗口上的按钮有个command选项,其实它就是一个函数。如下:
import tkinterfrom functools import partialdef hello(): lb.config(text="Nice to meet you!")def doing(): lb.config(text="What are you doing!")root = tkinter.Tk()lb = tkinter.Label(text = "Hi Cht!",font = "Times 26")b1 = tkinter.Button(root, fg ='white', bg = 'blue', text = 'Button b1',command = doing) # 不使用偏函数生成按钮MyBtn = partial(tkinter.Button, root, fg = 'white', bg = 'blue') # 使用偏函数定义MyBtnb2 = MyBtn(text='Button b2',command = hello )b3 = MyBtn(text='quit', command = root.quit)lb.pack()b1.pack()b2.pack()b3.pack()root.mainloop()
结果输出:
按下Button 1和Button 2就会执行hello和doing两个函数。这两个函数非常类似,如果有10个按钮,并且都是类似的呢?
换成内部函数、闭包的的语法如下:import tkinterfrom functools import partialdef hello(world): def doing(): lb.config(text="Hello %s!" % world) return doing # hello函数的返回值还是函数root = tkinter.Tk()lb = tkinter.Label(text = "Hi Cht!",font = "Times 26")b1 = tkinter.Button(root, fg ='white', bg = 'blue', text = 'Button b1',command = hello('Cht')) # 不使用偏函数生成按钮MyBtn = partial(tkinter.Button, root, fg = 'white', bg = 'blue') # 使用偏函数定义MyBtnb2 = MyBtn(text='Button b2',command = hello('Hjp') )b3 = MyBtn(text='quit', command = root.quit)lb.pack()b1.pack()b2.pack()b3.pack()root.mainloop()
效果一样: