python - 即使声明了类名也未定义

Question

我是 python GUI 编程新手，并且阅读了本教程，说明 Tkinter 使用

我尝试了以下代码

import Tkinter

class  simpleapp_tk(Tkinter.Tk):
     def __init__(self,parent):
           Tkinter.Tk.__init__(self,parent)
           self.parent=parent
           self.initialize()

  def initialize(self):
        pass
  if  __name__=="__main__":
        app=simpleapp_tk(None)
        app.title('my application')
        app.mainloop()

我本以为会出现一个空白窗口，但结果却是这个

 Traceback (most recent call last):
  File "C:/Users/vedev/Desktop/python/app1.py", line 3, in <module>
    class  simpleapp_tk(Tkinter.Tk):
  File "C:/Users/vedev/Desktop/python/app1.py", line 12, in simpleapp_tk
app=simpleapp_tk(None)
NameError: name 'simpleapp_tk' is not defined

如何调试它？

Answer 1

这是你的缩进问题。只是不要缩进

if __name__ == "__main__":
    app = simpleapp_tk(None)
    app.title('my application')
    app.mainloop()

在当前代码中，在定义 simpleapp_tk 时执行 if 语句，因此 name 'simpleapp_tk' 未定义。

参见Indentation

Leading whitespace (spaces and tabs) at the beginning of a logical line is used to compute the indentation level of the line, which in turn is used to determine the grouping of statements.