Question

以下是相关代码：

import wx


class MyFrame(wx.Frame):
    """
    This is MyFrame.  It just shows a few controls on a wxPanel,
    and has a simple menu.
    """

    def __init__(self, parent, title):
        wx.Frame.__init__(self, parent, -1, title,
                          pos=(150, 150), size=(350, 200))

        # Create the menubar
        menuBar = wx.MenuBar()

        # and a menu
        menu = wx.Menu()

        # add an item to the menu, using \tKeyName automatically
        # creates an accelerator, the third param is some help text
        # that will show up in the statusbar
        menu.Append(wx.ID_EXIT, "E&xit\tAlt-X", "Exit this simple sample")

        # bind the menu event to an event handler
        self.Bind(wx.EVT_MENU, self.OnTimeToClose, id=wx.ID_EXIT)

        # and put the menu on the menubar
        menuBar.Append(menu, "&File")
        self.SetMenuBar(menuBar)

        self.CreateStatusBar()

        # Now create the Panel to put the other controls on.
        panel = wx.Panel(self)

        # and a few controls
        text = wx.StaticText(panel, -1, self.istream)
        text.SetFont(wx.Font(14, wx.SWISS, wx.NORMAL, wx.BOLD))
        text.SetSize(text.GetBestSize())
        btn = wx.Button(panel, -1, "Close")
        funbtn = wx.Button(panel, -1, "Just for fun...")

        # bind the button events to handlers
        self.Bind(wx.EVT_BUTTON, self.OnTimeToClose, btn)
        self.Bind(wx.EVT_BUTTON, self.OnFunButton, funbtn)

        # Use a sizer to layout the controls, stacked vertically and with
        # a 10 pixel border around each
        sizer = wx.BoxSizer(wx.VERTICAL)
        sizer.Add(text, 0, wx.ALL, 10)
        sizer.Add(btn, 0, wx.ALL, 10)
        sizer.Add(funbtn, 0, wx.ALL, 10)
        panel.SetSizer(sizer)
        panel.Layout()


    def OnTimeToClose(self, evt):
        """Event handler for the button click."""
        print "See ya later!"
        self.Close()


    def OnFunButton(self, evt):
        """Event handler for the button click."""

        self.istream = raw_input('Press ENTER to EXIT...\n')


class MyApp(wx.App):

    def OnInit(self):
        frame = MyFrame(None, "Simple wxPython App")
        self.SetTopWindow(frame)

        print "Print statements go to this stdout window by default."

        frame.Show(True)
        return True


app = MyApp(redirect=True)
app.MainLoop()

我收到的错误是MyFrame对象没有属性istream。我不确定为什么这是真的，因为即使在代码浏览器下的PyScripter中，它也会将istream列为MyFrame的一个属性。我有一种感觉，我错过了一些非常基本的东西。有什么想法吗？

（顺便说一下，忽略缩进错误，它是由于代码块格式化造成的。）

Answer 1

__init__方法（期望定义self.istream）在定义OnFunButton的{{1}}方法之前执行。因此，您看到消息“MyFrame没有属性istream”，因为self.istream查找__init__，但尚未定义。

在使用变量之前，您需要定义self.istream。

引用其他模块中的对象

1 个答案: