异常AttributeError：“'HookManager'对象没有属性

Question

您好我是python编程的新手，我试图在按钮点击时截取所选区域的屏幕截图。它在第一次点击时按预期工作，但如果我想捕获多次，则会引发错误。

异常AttributeError：“'HookManager'对象在＆gt;中没有属性'keyboard_hook'”忽略

下面是我的代码。

class CaptureScreenshot(PyMouseEvent):

    app = wx.App() 
    dc = wx.ScreenDC() 
    dc.StartDrawingOnTop(None) 
    dc.SetPen(wx.Pen('green', 2)) 
    dc.SetBrush(wx.TRANSPARENT_BRUSH)
#    To draw the crosshair
    SetSystemCursor = windll.user32.SetSystemCursor #reference to function
    SetSystemCursor.argtype = [c_int, c_int] #arguments
    SetSystemCursor.restype = c_int #return
    LoadCursorFromFile = windll.user32.LoadCursorFromFileA #reference to function
    LoadCursorFromFile.argtype = c_char_p #arguments
    LoadCursorFromFile.restype = c_int #return
    CrossHeirPointer = "D:/ccrosshair.cur"
    NormalPointer = "D:/Arrow.cur"
    i = 0
    def __init__(self):

        PyMouseEvent.__init__(self)
        self.logger = Logger(self.__class__.__name__).get()
        NewCursor = self.LoadCursorFromFile(self.CrossHeirPointer)
        if NewCursor is None:
            print "Error loading the cursor"
        elif self.SetSystemCursor(NewCursor, win32con.IDC_ARROW) == 0:
            print "Error in setting the cursor"

    def click(self, x, y, button, press):

        if button == 1 and self.i == 0:

            global x1,y1,x2,y2
            if press:
                x1 = x
                y1 = y

            else:

                x2 = x 
                y2 = y

                self.i = self.i + 1
                self.dc.DrawRectangle(x1, y1, x2-x1, y2-y1)
                im = ImageGrab.grab(bbox=(x1,y1,x2,y2))
                time.sleep(0.5)
                try:
                    im.save("path to save the screenshot")
                    time.sleep(0.5)
                except Exception, err:
                    print "Wrong selection", Exception, err
                finally:

                    self.dc.EndDrawingOnTop()
                    self.dc.Clear()
                    NewCursor = self.LoadCursorFromFile(self.NormalPointer)
                    if NewCursor is None:
                        print "Error loading the cursor"
                    elif self.SetSystemCursor(NewCursor, win32con.IDC_ARROW) == 0:
                        print "Error in setting the cursor"

                    self.stop()
                    self = 'close'
        else:
            self.stop()



class test():
    w = tk.Tk()
    c = CaptureScreenshot()
    def __init__(self):
        self.logger = Logger(self.__class__.__name__).get()
        self.w.title("Test Window")
        self.w.minsize(500, 600)

    def capture(self):
        self.c.run()




t = test()
b = tk.Button(t.w, text = 'ok', command = t.capture, width = 40).pack()
t.w.mainloop()