A string list containing labels of values for one chart series.
property Labels: TRVStringList;
This string list must contain UTF-8 strings for Delphi 5-2007, and UTF-16 strings for newer versions of Delphi.
This property is used only if LabelsValueString is empty.
Use TRichViewEdit.SetCurrentItemExtraStrPropertyEx to change Labels.Text as an editing operation (rvespcSeries0 + rvespc_Inc_Series_Labels + Index * rvespc_Series_Prop_MaxCount, where Index is the index in the collection).