Python tkInter入门乐趣

Question

玩弄 Python - tkInter - Entry 小部件 - 当我使用 validatecommand(如下)时，第一次检查字符串 > Max，但是当我继续输入文本时检查步骤 - 在第一次？有什么建议吗？ (除了不通过 python 构建桌面应用程序之外)

---

#!/usr/bin/env python
from Tkinter import *

class MyEntry(Entry):

    def __init__(self, master, maxchars):
        Entry.__init__(self, master, validate = "key",    validatecommand=self.validatecommand)
        self.MAX = maxchars

    def validatecommand(self, *args):
        if len(self.get()) >= self.MAX:
            self.delete(0,3)
            self.insert(0, "no")
        return True

if __name__ == '__main__':
    tkmain = Tk()
    e = MyEntry(tkmain, 5)
    e.grid()
    tkmain.mainloop()

Answer 1

From the Tk man :

The validate option will also set itself to none when you edit the entry widget from within either the validateCommand or the invalidCommand. Such editions will override the one that was being validated. If you wish to edit the entry widget (for example set it to {}) during validation and still have the validate option set, you should include the command

after idle {%W config -validate %v}

不知道如何将其转换为 python。