lazarus-tutorials/polymorphic class/unitmain.pas

unit unitmain;

{$mode objfpc}{$H+}

interface

uses
	Classes, SysUtils, Forms, Controls, Graphics, Dialogs, ExtCtrls, person;

type

{ TMainform }
TMainform = class(TForm)
		rgPeople: TRadioGroup;
		procedure FormCreate(Sender: TObject);
		procedure rgPeopleClick(Sender: TObject);
	end;

var
	Form1: TMainform;

implementation

{$R mainform.lfm}

{ TMainform }

procedure TMainform.FormCreate(Sender: TObject);
begin

end;

procedure TMainform.rgPeopleClick(Sender: TObject);
var p: TPerson;
begin
	if rgPeople.ItemIndex < 0 then Exit;

	// Select the appropriate Person
	case rgPeople.ItemIndex of
		0: p := TBeckham.Create;
		1: p := TShakespeare.Create;
		2: p := TWest.Create;
		3: p := TBlaise.Create;
	end;

	p.Speak;
	p.Free;
end;

end.