Paging when using collection

[RobinBronsteede]

I just implemented the control to show data to users in a custom page, in this scenario a collection is used. Sorting and filtering works fine, but it looks like paging doesn't work

Page size is set to 50 (collection has 251 records)
grid.TotalRecords shows -1 (where 251 is expected)
grid.HasNextPage en grid.HasPreviousPage show true/false as expected

OnSelect: UpdateContext({ctxGridEvent:"LoadNextPage" & Text(Rand())}) => No action is shown

Is this as expected according the code and my situation?