listctrl.ColumnSorterMixin sorting problem

Hello,

I'm running into a problem sorting listctrl.ColumnSorterMixin. initial
items of list, it works perfectly. When listctrl is cleared and reloaded
with new items, it only sorts in ascending order. It seems that in fact on
click on column title, it first sorts in descending order then immediately
in ascending, so that what you see is only the results of the last sorting.

I searched for answers in google and found a few questions that mention the
same exact problem, but the answer that was given in one case, to call
SortListItems after reloading items in listctrl, does not help. Here's what
I'm doing:

class MyFrame(wx.Frame, MyColSortMix):

[]
(self, numCols)
(self)

I tried several different ways of doing this but nothing seems to help

Am I doing it the right way here?:

index = self.lc.InsertStringItem(sys.maxint, show_title)

self.lc.SetItemData(index, index)

where self.lc is my listctrl

thanks, -ak