I didn't knew of any such class name
PageOffsetList
, so I Googled it. I didn't find anything as such.
As thought, it was surely a custom class written by someone (surely not you as you are not aware of it.). Looking at the links, found the source from where it looks like the code was copied which you are referring now.
Add this in your code behind class:
class PageOffsetList : System.ComponentModel.IListSource
{
public bool ContainsListCollection { get; protected set; }
public System.Collections.IList GetList()
{
var pageOffsets = new List<int>();
for (int offset = 0; offset < totalRecords; offset += pageSize)
pageOffsets.Add(offset);
return pageOffsets;
}
}
It has been referred/copied/used from here in your code base:
Solution 2 here[
^]