学步园

procedure TForm1.ToolBar1CustomDraw(Sender: TToolBar; const ARect: TRect;
  var DefaultDraw: Boolean);
var
 i,j : Integer;
 Dct : TRect;
begin
 j := ToolBar1.Height;
 for i:=0 to (ToolBar1.Width - 1) div 2 do
 begin
  ToolBar1.Canvas.Brush.Color := RGB(255, 255, Trunc(2*255*i/ToolBar1.Width));
    Dct := Rect(ToolBar1.Left + i*2,
               ToolBar1.Top + 1,
               ToolBar1.Left + (i+1)*2,
               ToolBar1.Top + 1 + ToolBar1.Height - 2);
   ToolBar1.Canvas.FillRect(Dct);
 end;
end;