Постепенное заполнение ProgressBar-а после нажатия на кнопку

unit vr;
 
{$mode objfpc}{$H+}
 
interface
 
uses
  Classes, SysUtils, ExtCtrls, Dialogs;
 
TYPE TState=(Play,Pause,Stop);
TYPE
  TPO = procedure of object;
 
  TVideoRecorder = class
   private
    v_power: boolean;
    v_currentTimeVR: Ttime;
    v_stateCassette: TState;
    v_title: string;
    v_p: TPO;
    timer: Ttimer;
    procedure setCurrentTimeVR(newCurrentTimeVR: Ttime);
    procedure setStateCassette(newStateCassette: TState);
    procedure setTitle(newTitle: string);
    function getPower: boolean;
    function getCurrentTimeVR: Ttime;
    function getStateCassette: TState;
    function getTitle: string;
 
 
    public
     property power: boolean read getPower;
     property currentTimeVR: Ttime read getCurrentTimeVR write setCurrentTimeVR;
     property stateCassette: TState read getStateCassette write setStateCassette;
     property title: string read getTitle write setTitle;
 
    procedure swtchPower;
    procedure play;
    procedure pause;
    procedure stop;
    procedure rewindBack(rewindBack: Ttime);
    procedure rewindFoward(rewindFoward: Ttime);
    procedure removCassette;
    procedure setCassette(newTitle: string);
 
    procedure Timer1Timer(Sender: TObject);
 
    constructor Create(p: TPO);
    destructor Destroy;
  end;
  VAR a,b,c:TState;
      //a:Play;b:=Stop;c:=Pause;
    //progressBar1.position:=p;
 
implementation
constructor TVideoRecorder.Create(p: TPO);
begin
  inherited Create;
 
  v_power:= false;
  v_currentTimeVR:=now;
  v_stateCassette:=b;
  v_title:=('имя кассеты');
 
  //Создание таймера
  timer:=TTimer.Create(nil);
  timer.Enabled:=true;
  timer.Interval:=1000;
  timer.OnTimer:=@Timer1Timer;
 
  v_p:=p;
 
end;
 
destructor TVideoRecorder.Destroy;
begin
  timer.Enabled:=false;
  timer.Destroy;
 
  inherited Destroy;
  end;
procedure TVideoRecorder.Timer1Timer(Sender: Tobject);
begin
 //video.currentTimeVR:= ;
end;
procedure TVideoRecorder.setCurrentTimeVR(newCurrentTimeVR: Ttime);
begin
 v_currentTimeVR:=newCurrentTimeVR;
end;
procedure TVideoRecorder.setStateCassette(newStateCassette: TState);
begin
 v_stateCassette:=newStateCassette;
end;
procedure TVideoRecorder.setTitle(newTitle: string);
begin
 v_title:=newTitle;
end;
procedure TVideoRecorder.swtchPower;
begin
 v_power:=not(v_power);
 if Assigned(v_p) then
 v_p;
end;
procedure TVideoRecorder.play;
begin
 v_stateCassette:=a;
 timer.Enabled:=true;
 //progressBar1.Position = 100;
 if Assigned(v_p) then
 v_p
end;
procedure TVideoRecorder.pause;
begin
 v_stateCassette:=c;
end;
procedure TVideoRecorder.stop;
begin
 v_stateCassette:=b;
end;
procedure TVideoRecorder.rewindBack(rewindBack: Ttime);
begin
 
end;
procedure TVideoRecorder.rewindFoward(rewindFoward: Ttime);
begin
 
end;
procedure TVideoRecorder.setCassette(newTitle: string);
begin
 
end;
function TVideoRecorder.getPower: boolean;
begin
 result:=v_power;
end;
function TVideoRecorder.getCurrentTimeVR: Ttime;
begin
 result:=v_currentTimeVR;
end;
function TVideoRecorder.getStateCassette: TState;
begin
 result:=v_stateCassette;
end;
function TVideoRecorder.getTitle: string;
begin
 result:=v_title;
end;
procedure TVideoRecorder.removCassette;
begin
 
end;
end.