Occurs when a stream is involved in a potentially slow process.
TECLProgressEvent = procedure (Sender: TObject;PercentDone: Real) of object;
property OnProgress: TECLProgressEvent;
OnProgress occurs during such processes as reading, writing, loading, saving and changing compression level and encryption. OnProgress allows applications to provide the user with feedback about the progress of the slow process.
The PercentDone parameter is an approximation of how much of the operation has completed. Use PercentDone to update the position of a progress bar or other indicator.