Can I still resize column and rows when no headers are visible?

If you want to enable tracking the grid lines anywhere in the grid, you can call

   GetParam( )->EnableTrackColWidth(GX_TRACK_DEFAULT | GX_TRACK_EXTHITTEST | GX_TRACK_NOTHEADEER);
   GetParam( )->EnableTrackRowHeight(GX_TRACK_DEFAULT | GX_TRACK_EXTHITTEST | GX_TRACK_NOTHEADEER);

The GridApp “Welcome” tab demonstrates this setting.