procedure SetUpdateState(Updating: Boolean); virtual;
virtual void __fastcall SetUpdateState(bool Updating);
Performs internal adjustments before or after a series of updates.
SetUpdateState is called at the beginning or end of a series of updates. When the BeginUpdate method is first called and the TStrings object is not already in the middle of an update, TStrings calls SetUpdateState internally, with Updating set to true. When the EndUpdate method is called and it cancels out the last unmatched call to BeginUpdate, TStrings calls SetUpdateState internally, with Updating set to false.