unit DesignerOverridesUnit;
interface
uses ExtCtrls;
type
  // Cвоя копия TPanel, отличающаяся от системной тем, что у этой ParentBackground default False;
  // А то есть задизайненные формочки, где прозрачные панели показывают неприглядное исподнее...
  // Нужно, чтоб по умолчанию панели продолжали быть непрозрачными.
  // Заодно умеет перекрашиваться в спец-светлый, если обнаруживает себя лежащей на TTabSheet
  TPanel = class(TCustomPanel)
  protected
    procedure SetParent(AParent: TWinControl); override;
  public
    constructor Create(AOwner: TComponent); override;
    property DockManager;
  published
    property Align;
    property Alignment;
    property Anchors;
    property AutoSize;
    property BevelEdges;
    property BevelInner;
    property BevelKind;
    property BevelOuter;
    property BevelWidth;
    property BiDiMode;
    property BorderWidth;
    property BorderStyle;
    property Caption;
    property Color;
    property Constraints;
    property Ctl3D;
    property UseDockManager default True;
    property DockSite;
    property DoubleBuffered;
    property DragCursor;
    property DragKind;
    property DragMode;
    property Enabled;
    property FullRepaint;
    property Font;
    property Locked;
    property Padding;
    property ParentBiDiMode;
    property ParentBackground default False;
    property ParentColor;
    property ParentCtl3D;
    property ParentDoubleBuffered;
    property ParentFont;
    property ParentShowHint;
    property PopupMenu;
    property ShowCaption;
    property ShowHint;
    property TabOrder;
    property TabStop;
    property Touch;
    property VerticalAlignment;
    property Visible;
    property StyleElements;
    property OnAlignInsertBefore;
    property OnAlignPosition;
    property OnCanResize;
    property OnClick;
    property OnConstrainedResize;
    property OnContextPopup;
    property OnDockDrop;
    property OnDockOver;
    property OnDblClick;
    property OnDragDrop;
    property OnDragOver;
    property OnEndDock;
    property OnEndDrag;
    property OnEnter;
    property OnExit;
    property OnGesture;
    property OnGetSiteInfo;
    property OnMouseActivate;
    property OnMouseDown;
    property OnMouseEnter;
    property OnMouseLeave;
    property OnMouseMove;
    property OnMouseUp;
    property OnResize;
    property OnStartDock;
    property OnStartDrag;
    property OnUnDock;
  end;

implementation
uses ComCtrls, Themes, UxTheme;
{ TPanel }

constructor TPanel.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
  ParentBackground := False;
end;

procedure TPanel.SetParent(AParent: TWinControl);
var
  p: TWinControl;
  TabTheme: HTHEME;
  TabColor: Cardinal;
begin
  inherited;
  p := AParent;
  while Assigned(p) and not (p is TTabSheet) do
    p := p.Parent;
  if Assigned(p) then
    if ThemeServices.ThemesEnabled then
      begin
        TabTheme := ThemeServices.Theme[teTab];
        try
          if GetThemeColor(TabTheme, TABP_AEROWIZARDBODY, 0, TMT_FILLCOLORHINT, TabColor) = S_OK then
            Color := TabColor;
        finally
//          CloseThemeData(TabTheme);
        end;
      end;
end;