[3.delphi common components] 6 scroll bar

6. Scroll bar

In general , Scrollbars are added automatically . If you plan to control the scrolling of the window by yourself , You can use the scroll bar （TScrollBar） Components . Its main properties are as follows ：

attribute	explain
LargeChange	Set when the user clicks the scroll bar （ Non arrow part ） Rolling distance
Max	Maximum scrollable value
Min	Minimum scrollable value
PageSize	Press down PgUp、PgDn The scrolling distance of the scroll bar when pressing the key
Position	Sets or returns the position of the square in the scroll bar
SmallChange	Click the arrows at both ends of the scroll bar to scroll the distance

The main method ：

Method	explain
SetParams	This procedure is used to set Position、Max and Min attribute

Major events ：

event	explain
OnScroll	Event triggered when the user operates the scroll bar , among , The second parameter returns the status of the scroll bar , The third parameter returns the position of the scroll bar box

Example ： Display the current position when the square position of the scroll bar changes , The interface is as follows ：

 

The code is as follows ：

procedure TForm1.ScrollBar1Scroll(Sender: TObject; ScrollCode: TScrollCode;
  var ScrollPos: Integer);
begin
  Label1.Caption := ' The current position ：' + IntToStr(ScrollBar1.Position);
end;