{-----------------------------------------------------------------------------
The contents of this file are subject to the Mozilla Public License
Version 1.1 (the "License"); you may not use this file except in compliance
with the License. You may obtain a copy of the License at
http://www.mozilla.org/MPL/MPL-1.1.html

Software distributed under the License is distributed on an "AS IS" basis,
WITHOUT WARRANTY OF ANY KIND, either expressed or implied. See the License for
the specific language governing rights and limitations under the License.

The Original Code is: JvScrollBar.PAS, released on 2001-02-28.

The Initial Developer of the Original Code is Sébastien Buysse [sbuysse@buypin.com]
Portions created by Sébastien Buysse are Copyright (C) 2001 Sébastien Buysse.
All Rights Reserved.

Contributor(s): Michael Beck [mbeck@bigfoot.com].

Last Modified: 2000-02-28

You may retrieve the latest version of this file at the Project JEDI's JVCL home page,
located at http://jvcl.sourceforge.net

Known Issues:
-----------------------------------------------------------------------------}

{$I JVCL.INC}

unit JvScrollBar;

interface

uses
  Messages, SysUtils, Classes, Graphics, Controls, Forms, StdCtrls,
  JVCLVer;

type
  TJvScrollBar = class(TScrollBar)
  private
    FAboutJVCL: TJVCLAboutInfo;
    FHintColor: TColor;
    FSaved: TColor;
    FOnMouseEnter: TNotifyEvent;
    FOnMouseLeave: TNotifyEvent;
    FOnCtl3DChanged: TNotifyEvent;
    FOnParentColorChanged: TNotifyEvent;
    FHotTrack: Boolean;
    FOver: Boolean;
    procedure SetHotTrack(Value: Boolean);
  protected
    procedure CMMouseEnter(var Msg: TMessage); message CM_MOUSEENTER;
    procedure CMMouseLeave(var Msg: TMessage); message CM_MOUSELEAVE;
    procedure CMCtl3DChanged(var Msg: TMessage); message CM_CTL3DCHANGED;
    procedure CMParentColorChanged(var Msg: TMessage); message CM_PARENTCOLORCHANGED;
  public
    constructor Create(AOwner: TComponent); override;
  published
    property AboutJVCL: TJVCLAboutInfo read FAboutJVCL write FAboutJVCL stored False;
    property HotTrack: Boolean read FHotTrack write SetHotTrack default False;
    property HintColor: TColor read FHintColor write FHintColor default clInfoBk;
    property OnMouseEnter: TNotifyEvent read FOnMouseEnter write FOnMouseEnter;
    property OnMouseLeave: TNotifyEvent read FOnMouseLeave write FOnMouseLeave;
    property OnCtl3DChanged: TNotifyEvent read FOnCtl3DChanged write FOnCtl3DChanged;
    property OnParentColorChange: TNotifyEvent read FOnParentColorChanged write FOnParentColorChanged;
  end;

implementation

constructor TJvScrollBar.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
  FHintColor := clInfoBk;
  FOver := False;
  FHotTrack := False;
  ControlStyle := ControlStyle + [csAcceptsControls];
end;

procedure TJvScrollBar.CMCtl3DChanged(var Msg: TMessage);
begin
  inherited;
  if Assigned(FOnCtl3DChanged) then
    FOnCtl3DChanged(Self);
end;

procedure TJvScrollBar.CMParentColorChanged(var Msg: TMessage);
begin
  inherited;
  if Assigned(FOnParentColorChanged) then
    FOnParentColorChanged(Self);
end;

procedure TJvScrollBar.CMMouseEnter(var Msg: TMessage);
begin
  if not FOver then
  begin
    FSaved := Application.HintColor;
    // for D7...
    if csDesigning in ComponentState then
      Exit;
    Application.HintColor := FHintColor;
    if FHotTrack then
      Ctl3D := True;
    FOver := True;
  end;
  if Assigned(FOnMouseEnter) then
    FOnMouseEnter(Self);
end;

procedure TJvScrollBar.CMMouseLeave(var Msg: TMessage);
begin
  if FOver then
  begin
    Application.HintColor := FSaved;
    if FHotTrack then
      Ctl3D := False;
    FOver := False;
  end;
  if Assigned(FOnMouseLeave) then
    FOnMouseLeave(Self);
end;

procedure TJvScrollBar.SetHotTrack(Value: Boolean);
begin
  FHotTrack := Value;
  if FHotTrack then
    Ctl3D := False;
end;

end.

