private synchronized void doShowSalesReport() {

    BackOfficeWindow window = BackOfficeWindow.getInstance();
    JTabbedPane tabbedPane = window.getTabbedPane();

    ReportViewer viewer = null;
    //        int index = tabbedPane.indexOfTab(com.floreantpos.POSConstants.SALES_REPORT);
    int index = tabbedPane.indexOfTab("Transaksi Harian");
    if (index == -1) {
      //            viewer = new ReportViewer(new SalesReport());
      viewer = new ReportViewer(new DailyTxnReport());
      //            tabbedPane.addTab(POSConstants.SALES_REPORT, viewer);
      tabbedPane.addTab("Transaksi Harian", viewer);
    } else {
      viewer = (ReportViewer) tabbedPane.getComponentAt(index);
    }
    tabbedPane.setSelectedComponent(viewer);

    window.setVisible(true);
  }