感觉是全新的学习了。

因为在以前的工作中，并没有有意识的去运用哪一种编程模式。

以后要注意的了。

这才是高手之路呀~

 

class Event:    def __init__(self, name):        self.name = name    def __str__(self):        return self.nameclass Widget:    def __init__(self, parent=None):        self.parent = parent    def handle(self, event):        handler = 'handle_{}'.format(event)        if hasattr(self, handler):            method = getattr(self, handler)            method(event)        elif self.parent:            self.parent.handle(event)        elif hasattr(self, 'handle_default'):            self.handle_default(event)class MainWindow(Widget):    def handle_close(self, event):        print('MainWindow: {}'.format(event))    def handle_default(self, event):        print('MainWindows Default: {}'.format(event))class SendDialog(Widget):    def handle_paint(self, event):       print('SendDialog : {}'.format(event))class MsgText(Widget):    def handle_down(self, event):        print('MsgText: {}'.format(event))def main():    mw = MainWindow()    sd = SendDialog(mw)    msg = MsgText(sd)    for e in ('down', 'paint', 'unhandled', 'close'):        evt = Event(e)        print('\nSending event - {} - to MainWindow'.format(evt))        mw.handle(evt)        print('\nSending event - {} - to SendDialog'.format(evt))        sd.handle(evt)        print('\nSending event - {} - to MsgText'.format(evt))        msg.handle(evt)if __name__ == '__main__':    main()