Prepare OnBusy event for long-term operation.
// Delphi public procedure BusyPrepare( _sender : TObject; _text : String );
// C++ Builder public: void BusyPrepare( TObject* _sender, UnicodeString _text ) = 0;
|_sender||TObject||component which is causing long-term operations|
|_text||String||text to appear in a BusyText property; predefined GIS_BUSY_NOEVENTS and GIS_BUSY_NOHOURGLASS could be used to define "silent" busy state; in such state OnBusy event will not be called and, in a case of GIS_BUSY_NOHOURGLASS, hourglass will not be displayed and check for interrupt as well.|
Do not use during OnPaint event directly. Must be paired with BusyRelease. The actual state can be obtained from IsBusy property.