unit Unit1;

interface

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

const
  PROGRESS_POS = WM_USER+1;

type
  TForm1 = class(TForm)
    Button2: TButton;
    ProgressBar2: TProgressBar;
    Button3: TButton;
    ProgressBar3: TProgressBar;
    Button4: TButton;
    ProgressBar4: TProgressBar;
    XPManifest1: TXPManifest;
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
    procedure Button4Click(Sender: TObject);
    procedure FormCreate(Sender: TObject);
  private
        procedure SetProgressPos(var Msg: TMessage); message PROGRESS_POS;
  public
    { Public declarations }
  end;

  // Для показа примеров я создам
  // 3 разных класса, наследника TThread

  TSyncThread = class(TThread)
  private
    Progress: integer;
    procedure SetProgress;
  protected
    procedure Execute; override;
  end;

  TMessageThread = class(TThread)
  private
  protected
    procedure Execute; override;
  end;

  TCriricalThread = class(TThread)
  private
  protected
    procedure Execute; override;
  end;

var
  Form1: TForm1;
  CriticalSection: TCriticalSection;

implementation

{$R *.dfm}

{ TSyncThread }

procedure TSyncThread.Execute;
var
  i: integer;
begin
  for i:=0 to 100 do
  begin
    sleep(50);
    Progress:=i;
    Synchronize(SetProgress);
  end;
end;

procedure TSyncThread.SetProgress;
begin
  Form1.ProgressBar2.Position:=Progress;
end;

{ TMessageThread }

procedure TMessageThread.Execute;
var
  i: integer;
begin
  for i:=0 to 100 do
  begin
    sleep(50);
    // в WParam передаём, какой ProgressBar крутить
    SendMessage(Form1.Handle,PROGRESS_POS,0,i);
  end;
end;

{ TCriricalThread }

procedure TCriricalThread.Execute;
var
  i: integer;
begin
  CriticalSection.Enter;
  for i:=0 to 100 do
  begin
    sleep(50);
    // в WParam передаём, какой ProgressBar крутить
    SendMessage(Form1.Handle,PROGRESS_POS,1,i);
  end;
  CriticalSection.Leave;
end;


{ TForm1 }

procedure TForm1.SetProgressPos(var Msg: TMessage);
begin
  case Msg.WParam of
    0: ProgressBar3.Position:=Msg.LParam;
    1: ProgressBar4.Position:=Msg.LParam;
  end;
end;

procedure TForm1.Button2Click(Sender: TObject);
var
  SyncThread: TSyncThread;
begin
  SyncThread:=TSyncThread.Create(true);
  SyncThread.FreeOnTerminate:=true;
  SyncThread.Priority:=tpLower;
  // SyncThread.Resume;
  SyncThread.Start;
end;

procedure TForm1.Button3Click(Sender: TObject);
var
  MessageThread: TMessageThread;
begin
  MessageThread:=TMessageThread.Create(true);
  MessageThread.FreeOnTerminate:=true;
  MessageThread.Priority:=tpLower;
  // MessageThread.Resume;
  MessageThread.Start;
end;

procedure TForm1.Button4Click(Sender: TObject);
var
  CriricalThread: TCriricalThread;
begin
  CriricalThread:=TCriricalThread.Create(true);
  CriricalThread.FreeOnTerminate:=true;
  CriricalThread.Priority:=tpLower;
  // CriricalThread.Resume;
  CriricalThread.Start;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
   CriticalSection:=TCriticalSection.Create;
end;

end.