wxpython菜单不显示图像

我正在创建一个菜单并为菜单项分配图像,有时菜单中的第一项不显示任何图像,我找不到原因。我试着做一个简单的独立的例子,下面的代码在我的机器上演示了这个问题。 我使用的是Windows XP、WX 2.8.7.1(MSW Unicode)'

import wx

def getBmp():
    bmp = wx.EmptyBitmap(16,16)
    return bmp

class MyFrame(wx.Frame):
    def __init__(self):
        wx.Frame.__init__(self, style=wx.DEFAULT_FRAME_STYLE, parent=None)

        self.SetTitle("why New has no image?")

        menuBar = wx.MenuBar()
        fileMenu=wx.Menu()
        item = fileMenu.Append(wx.ID_NEW, "New")
        item.SetBitmap(getBmp())
        item = fileMenu.Append(wx.ID_OPEN, "Open")
        item.SetBitmap(getBmp())
        item = fileMenu.Append(wx.ID_SAVE, "Save")
        item.SetBitmap(getBmp())
        menuBar.Append(fileMenu, "File")
        self.SetMenuBar(menuBar) 


app = wx.PySimpleApp()
frame=MyFrame()
frame.Show()
app.SetTopWindow(frame)
app.MainLoop()

那么你能看到问题所在吗?原因是什么?

结论 :是的,这是一个官方错误,我创建了一个简单的菜单类来克服这个错误,使用“balpha”在所选答案中给出的技巧。

它重写每个menu.append方法,并查看是否第一次添加带有图像的菜单项,如果是,则创建一个虚拟项,稍后将其删除。

这还添加了功能/约束,这样就不必调用setbitmap,而是应该将bitmap作为可选参数image传递。

import wx

class MockMenu(wx.Menu):
    """
    A custom menu class in which image param can be passed to each Append method
    it also takes care of bug http://trac.wxwidgets.org/ticket/4011
    """

    def __init__(self, *args, **kwargs):
        wx.Menu.__init__(self, *args, **kwargs)
        self._count = 0

    def applyBmp(self, unboundMethod, *args, **kwargs):
        """
        there is a bug in wxPython so that it will not display first item bitmap
        http://trac.wxwidgets.org/ticket/4011
        so we keep track and add a dummy before it and delete it after words
        may not work if menu has only one item
        """

        bmp = None
        if 'image' in kwargs:
            bmp = kwargs['image']

        tempitem = None
        # add temp item so it is first item with bmp 
        if bmp and self._count == 1:
            tempitem = wx.Menu.Append(self, -1,"HACK")
            tempitem.SetBitmap(bmp)

        ret = unboundMethod(self, *args, **kwargs)
        if bmp:
            ret.SetBitmap(bmp)

        # delete temp item
        if tempitem is not None:
            self.Remove(tempitem.GetId())

        self._lastRet = ret
        return ret

    def Append(self, *args, **kwargs):
        return self.applyBmp(wx.Menu.Append, *args, **kwargs)

    def AppendCheckItem(self, *args, **kwargs):
        return self.applyBmp(wx.Menu.AppendCheckItem, *args, **kwargs)

    def AppendMenu(self, *args, **kwargs):
        return self.applyBmp(wx.Menu.AppendMenu, *args, **kwargs)