type
  TSizeGrip = class(TWinControl)
  protected
    procedure CreateParams(var Params: TCreateParams); override;
    procedure CreateWnd; override;
  public
    constructor Create(aOwner: TComponent); override;
  end;

implementation

uses Windows;

{ TSizeGrip }

constructor TSizeGrip.Create(aOwner: TComponent);
begin
  inherited;

  ControlStyle := [csOpaque, csFixedWidth, csFixedHeight];

  Anchors := [akRight, akBottom];
  Cursor := crSizeNWSE;
  Height := 11;
  Width := 11;
end;

procedure TSizeGrip.CreateParams(var Params: TCreateParams);
begin
  inherited;
  CreateSubClass(Params, 'SCROLLBAR');
  Params.Style := Params.Style or WS_CLIPSIBLINGS or SBS_SIZEGRIP;
end;

procedure TSizeGrip.CreateWnd;
begin
  inherited;
  Left := Parent.ClientWidth - Width - 1;
  Top := Parent.ClientHeight - Height - 1;
  SendToBack;
end;