Отслеживать имя текущего компонента

unit FCForm;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  ComCtrls, StdCtrls;

type
  TForm1 = class(TForm)
    Edit1: TEdit;
    Edit2: TEdit;
    Edit3: TEdit;
    StatusBar1: TStatusBar;
  public
    procedure CmFocusChanged (var Msg: TCmFocusChanged);
      message cm_FocusChanged;
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.CmFocusChanged (var Msg: TCmFocusChanged);
begin
  StatusBar1.SimpleText := Msg.Sender.Name;
end;

end.