The scroll bar component is used to provide numerical input from a graphical object, as the bar is moved its value is changed and can be captured for use in the application.
For example:
procedure TForm1.ScrollBar1Change(Sender: TObject);
begin
Edit1.Text:=IntToStr(ScrollBar1.Position);
end;
This could be used to collect input for a chart or for a scientific demonstration.
Kind - sbVertical, sbHorizontal
Large Change - change in value from clicking on light grey scroll part of scrollbar.
Small Change - change in value from clicking on arrows in scrollbar.
Max - largest value in output range of scroll bar
Min - smallest value in output range of scroll bar
Position - provides current position of thumb tab in scroll bar and so the output value.
Many controls have their own integral scroll bars but for those that do not the scroll bar control can be added to give them a scroll bar facility.