Edit Cell in Grid with focus

I work with wxpython 4.1 and python 3.9
When I use grid edit with wx.EVT_KEY_DOWN when cell active I show a dialog box and in it
I have a search ctrl and DataViewListCtrl in search
i use wx.EVT_CHAR also have EVT_DATAVIEW_ITEM_ACTIVATED when i use downkey program exited without any error
I get character code from EVT_CHAR and if eqal wx.WXK_DOWN focus to dataviewlistctrl
where is the bug of program?