entry-with-shared-variable.py 文件源码

def __init__(self, master=None):
        Frame.__init__(self, master)
        self.pack()

        self.entrythingy = Entry(self)
        self.entrythingy.pack()

        self.button = Button(self, text="Uppercase The Entry",
                             command=self.upper)
        self.button.pack()

        # here we have the text in the entry widget tied to a variable.
        # changes in the variable are echoed in the widget and vice versa.
        # Very handy.
        # there are other Variable types. See Tkinter.py for all
        # the other variable types that can be shadowed
        self.contents = StringVar()
        self.contents.set("this is a variable")
        self.entrythingy.config(textvariable=self.contents)

        # and here we get a callback when the user hits return. we could
        # make the key that triggers the callback anything we wanted to.
        # other typical options might be <Key-Tab> or <Key> (for anything)
        self.entrythingy.bind('<Key-Return>', self.print_contents)