Cara Menampilkan Chart Kosong google piechart saat tidak ada data dalam tabel

  <script type="text/javascript">
         google.charts.load('current',  {packages: ["corechart","calendar","table"]});
        google.charts.setOnLoadCallback(drawChart);

          function drawChart()
          {
               var data = new google.visualization.DataTable();
               data.addColumn('string', 'Nama Barang');
               data.addColumn('number', 'Jumlah Transaksi');

                        data.addRows
                        ([
                              <?php
                              $coba = "";
                              $petik = "'";
                                  foreach ($dataPie_k as $row)
                                  {

                                    $coba = $coba."['$row->nama', $row->total],";
                                  }

                                      echo substr($coba,0,strlen($coba)-1);

                              ?>
                        ]);

            var options =
            {
              title: 'Rating 5',
              is3D: true,
              legend: 'none',

              pieSliceText: 'label',

            };

            var chart = new google.visualization.PieChart(document.getElementById('piechart'));

            chart.draw(data, options);

            }
    </script>

ini koding saya, saya ingin menampilkan chart kosong saat tidak ada data yang terambil