unit MainU;
 
 interface
 
 uses
   Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
   Dialogs, ComCtrls, StdCtrls, ExtCtrls;
 
 type
   //interceptor class
   TButton = class(StdCtrls.TButton)
     OwnedThread: TThread;
     ProgressBar: TProgressBar;
   end;
 
   TMyThread = class(TThread)
   private
     FCounter: Integer;
     FCountTo: Integer;
     FProgressBar: TProgressBar;
     FOwnerButton: TButton;
 
     procedure DoProgress;
     procedure SetCountTo(const Value: Integer) ;
     procedure SetProgressBar(const Value: TProgressBar) ;
     procedure SetOwnerButton(const Value: TButton) ;
   protected
     procedure Execute; override;
   public
     constructor Create(CreateSuspended: Boolean) ;
     property CountTo: Integer read FCountTo write SetCountTo;
     property ProgressBar: TProgressBar read FProgressBar write SetProgressBar;
     property OwnerButton: TButton read FOwnerButton write SetOwnerButton;
   end;
 
   TMainForm = class(TForm)
     Button1: TButton;
     ProgressBar1: TProgressBar;
     Button2: TButton;
     ProgressBar2: TProgressBar;
     Button3: TButton;
     ProgressBar3: TProgressBar;
     Button4: TButton;
     ProgressBar4: TProgressBar;
     Button5: TButton;
     ProgressBar5: TProgressBar;
     procedure Button1Click(Sender: TObject) ;
   end;
 
 var
   MainForm: TMainForm;
 
 implementation
 
 {$R *.dfm}
 
 { TMyThread }
 
 constructor TMyThread.Create(CreateSuspended: Boolean) ;
 begin
   inherited;
   FCounter := 0;
   FCountTo := MAXINT;
 end;
 
 procedure TMyThread.DoProgress;
 var
   PctDone: Extended;
 begin
   PctDone := (FCounter / FCountTo) ;
   FProgressBar.Position := Round(FProgressBar.Step * PctDone) ;
   FOwnerButton.Caption := FormatFloat('0.00 %', PctDone * 100) ;
 end;
 
 procedure TMyThread.Execute;
 const
   Interval = 1000000;
 begin
   FreeOnTerminate := True;
   FProgressBar.Max := FCountTo div Interval;
   FProgressBar.Step := FProgressBar.Max;
 
   while FCounter < FCountTo do
   begin
     if FCounter mod Interval = 0 then Synchronize(DoProgress) ;
 
     Inc(FCounter) ;
   end;
 
   FOwnerButton.Caption := 'Start';
   FOwnerButton.OwnedThread := nil;
   FProgressBar.Position := FProgressBar.Max;
 end;
 
 procedure TMyThread.SetCountTo(const Value: Integer) ;
 begin
   FCountTo := Value;
 end;
 
 procedure TMyThread.SetOwnerButton(const Value: TButton) ;
 begin
   FOwnerButton := Value;
 end;
 
 procedure TMyThread.SetProgressBar(const Value: TProgressBar) ;
 begin
   FProgressBar := Value;
 end;
 
 procedure TMainForm.Button1Click(Sender: TObject) ;
 var
   aButton: TButton;
   aThread: TMyThread;
   aProgressBar: TProgressBar;
 begin
   aButton := TButton(Sender) ;
   if not Assigned(aButton.OwnedThread) then
   begin
     aThread := TMyThread.Create(True) ;
     aButton.OwnedThread := aThread;
     aProgressBar := TProgressBar(FindComponent(StringReplace(aButton.Name, 'Button', 'ProgressBar', []))) ;
     aThread.ProgressBar := aProgressBar;
     aThread.OwnerButton := aButton;
     aThread.Resume;
     aButton.Caption := 'Pause';
   end
   else
   begin
     if aButton.OwnedThread.Suspended then
       aButton.OwnedThread.Resume
     else
       aButton.OwnedThread.Suspend;
 
     aButton.Caption := 'Run';
   end;
 end;
 
 end.