Event which is raised when the activeWorksheet of the Spreadsheet has changed. Function takes arguments evt and ui. Use ui.owner to obtain reference to igSpreadsheet. Use ui.oldActiveWorksheet to obtain the previous active worksheet. Use ui.oldActiveWorksheetName to obtain the name of the previous active worksheet or null if oldActiveWorksheet is null. Use ui.newActiveWorksheet to obtain the current active worksheet. Use ui.newActiveWorksheetName to obtain the name of the new active worksheet or null if newActiveWorksheet is null.
Target Platforms: Windows 8.1, Windows 8.1, Windows 8, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
