Server Side: 78564 entries
Client Side: a view screen of 20 entries
[Action #1: client wants to show the beginning of the list
Client:                            Server:            
          _offset: 1
    _contentCount: 0      --> 
     _beforeCount: 0
      _afterCount: 19
                                      
                          <==         _contentCount: 78564
                                    _targetPosition: 1
                                 (with 20 entries returned)
Action #2: client drags the scroll bar down to the bottom of the list
Client:                            Server:            
          _offset: 78564
    _contentCount: 78564  --> 
     _beforeCount: 19
      _afterCount: 0
                                      
                          <==         _contentCount: 78564
                                    _targetPosition: 78564
                                 (with 20 entries returned)
Action #3: client presses a page up key
Client:                            Server:            
          _offset: 78564-19-20
    _contentCount: 78564  --> 
     _beforeCount: 0
      _afterCount: 19
                                      
                          <==         _contentCount: 78564
                                    _targetPosition: 78525
                                 (with 20 entries returned)
[Action #4: client drags the scroll bar slider 68% of list
Client:                            Server:            
          _offset: 53424
    _contentCount: 78564  --> 
     _beforeCount: 9
      _afterCount: 10
                                      
                          <==         _contentCount: 78564
                                    _targetPosition: 53424
                                 (with 20 entries returned)
Action #5: client types XYZ to browse the list starting from XYZ 
Client:                            Server:            
greaterThanOrEqual: XYZ  
      _beforeCount: 0     -->
       _afterCount: 19
                                      
                          <==         _contentCount: 78564
                                    _targetPosition: 77777
                                 (with 20 entries returned)