TProgressBar

Code:

{

Use this ProgressBar when you do not know the amount of progress toward

completion but wish to indicate that progress is being made.

This ProgressBar works only on Windows XP and the ComCtl32.dll version

6.00 or later is needed. To use the new ComCtrl you have to provide the manifest.

In Delphi 7 just drop TXPManifest on the form. For prior versions of Delphi

you have to include the XP manifest resource.

}

unit MarqueeProgressBar;

interface

uses

  SysUtils, Windows, Classes, Controls, ComCtrls, Messages;

type

  TMarqueeProgressBar = class(TProgressBar)

  private

    FActive: Boolean;

    FAnimationSpeed: Integer;

    procedure SetActive(const Value: Boolean);

    procedure SetAnimationSpeed(const Value: Integer);

    procedure UpdateProgressBar;

  protected

    procedure CreateParams(var Params: TCreateParams); override;

  public

    constructor Create(AOwner: TComponent); override;

  published

    property Active: Boolean read FActive write SetActive;

    property AnimationSpeed: Integer read FAnimationSpeed write SetAnimationSpeed;

  end;

const

  PBS_MARQUEE  = $08;

  PBM_SETMARQUEE = WM_USER + 10;

procedure Register;

implementation

procedure Register;

begin

  RegisterComponents('SwissDelphiCenter', [TMarqueeProgressBar]);

end;

constructor TMarqueeProgressBar.Create(AOwner: TComponent);

begin

  inherited;

  FAnimationSpeed := 60;

end;

procedure TMarqueeProgressBar.CreateParams(var Params: TCreateParams);

begin

  inherited;

  Params.Style := Params.Style or PBS_MARQUEE;

end;

procedure TMarqueeProgressBar.SetActive(const Value: Boolean);

begin

  FActive := Value;

  UpdateProgressBar;

end;

procedure TMarqueeProgressBar.SetAnimationSpeed(const Value: Integer);

begin

  FAnimationSpeed := Value;

  UpdateProgressBar;

end;

procedure TMarqueeProgressBar.UpdateProgressBar;

begin

  if FActive then

    SendMessage(Self.Handle, PBM_SETMARQUEE, 1, FAnimationSpeed)

  else

    SendMessage(Self.Handle, PBM_SETMARQUEE, 0, 0);

end;

end.