title: DrillDown in multiple line graphs
body: <p>I am trying to get several line charts in one container and allow drill down in each of the line graphs. But I am not even able to plot the different line graphs at level 0. The data of the second line graph replaces the first one instead of plotting two graphs. Can you please help me out with this?</p>
  
  <p>Here is what I have: <a href="http://jsfiddle.net/JPzqn/7/" rel="nofollow">link</a></p>
  
  <pre><code>$(function () {
  var chart;
  $(document).ready(function() {
  
      var colors = Highcharts.getOptions().colors,
          categories = ['MSIE', 'Firefox', 'Chrome', 'Safari', 'Opera'],
          name = 'Browser brands 1',
          data = [{
                  y: 55.11,
                  color: colors[0],
                  drilldown: {
                      name: 'MSIE versions',
                      categories: ['MSIE 6.0', 'MSIE 7.0', 'MSIE 8.0', 'MSIE 9.0'],
                      data: [10.85, 7.35, 33.06, 2.81],
                      color: colors[0]
                  }
              }, {
                  y: 21.63,
                  color: colors[1],
                  drilldown: {
                      name: 'Firefox versions',
                      categories: ['Firefox 2.0', 'Firefox 3.0', 'Firefox 3.5', 'Firefox 3.6', 'Firefox 4.0'],
                      data: [0.20, 0.83, 1.58, 13.12, 5.43],
                      color: colors[1]
                  }
              }, {
                  y: 11.94,
                  color: colors[2],
                  drilldown: {
                      name: 'Chrome versions',
                      categories: ['Chrome 5.0', 'Chrome 6.0', 'Chrome 7.0', 'Chrome 8.0', 'Chrome 9.0',
                          'Chrome 10.0', 'Chrome 11.0', 'Chrome 12.0'],
                      data: [0.12, 0.19, 0.12, 0.36, 0.32, 9.91, 0.50, 0.22],
                      color: colors[2]
                  }
              }, {
                  y: 7.15,
                  color: colors[3],
                  drilldown: {
                      name: 'Safari versions',
                      categories: ['Safari 5.0', 'Safari 4.0', 'Safari Win 5.0', 'Safari 4.1', 'Safari/Maxthon',
                          'Safari 3.1', 'Safari 4.1'],
                      data: [4.55, 1.42, 0.23, 0.21, 0.20, 0.19, 0.14],
                      color: colors[3]
                  }
              }, {
                  y: 2.14,
                  color: colors[4],
                  drilldown: {
                      name: 'Opera versions',
                      categories: ['Opera 9.x', 'Opera 10.x', 'Opera 11.x'],
                      data: [ 0.12, 0.37, 1.65],
                      color: colors[4]
                  }
              }],
          name = 'Browser brands 2',
          data = [{
                  y: 25.11,
                  color: colors[0],
                  drilldown: {
                      name: 'MSIE versions',
                      categories: ['MSIE 6.0', 'MSIE 7.0', 'MSIE 8.0', 'MSIE 9.0'],
                      data: [10.85, 7.35, 33.06, 2.81],
                      color: colors[0]
                  }
              }, {
                  y: 41.63,
                  color: colors[1],
                  drilldown: {
                      name: 'Firefox versions',
                      categories: ['Firefox 2.0', 'Firefox 3.0', 'Firefox 3.5', 'Firefox 3.6', 'Firefox 4.0'],
                      data: [0.20, 0.83, 1.58, 13.12, 5.43],
                      color: colors[1]
                  }
              }, {
                  y: 31.94,
                  color: colors[2],
                  drilldown: {
                      name: 'Chrome versions',
                      categories: ['Chrome 5.0', 'Chrome 6.0', 'Chrome 7.0', 'Chrome 8.0', 'Chrome 9.0',
                          'Chrome 10.0', 'Chrome 11.0', 'Chrome 12.0'],
                      data: [0.12, 0.19, 0.12, 0.36, 0.32, 9.91, 0.50, 0.22],
                      color: colors[2]
                  }
              }, {
                  y: 17.15,
                  color: colors[3],
                  drilldown: {
                      name: 'Safari versions',
                      categories: ['Safari 5.0', 'Safari 4.0', 'Safari Win 5.0', 'Safari 4.1', 'Safari/Maxthon',
                          'Safari 3.1', 'Safari 4.1'],
                      data: [4.55, 1.42, 0.23, 0.21, 0.20, 0.19, 0.14],
                      color: colors[3]
                  }
              }, {
                  y: 23.14,
                  color: colors[4],
                  drilldown: {
                      name: 'Opera versions',
                      categories: ['Opera 9.x', 'Opera 10.x', 'Opera 11.x'],
                      data: [ 0.12, 0.37, 1.65],
                      color: colors[4]
                  }
              }]
          ;
  
      function setChart(name, categories, data, color) {
          chart.xAxis[0].setCategories(categories, false);
          chart.series[0].remove(false);
          chart.addSeries({
              name: name,
              data: data,
          }, false);
          chart.redraw();
      }
  
      chart = new Highcharts.Chart({
          chart: {
              renderTo: 'container',
              type: 'line'
          },
          title: {
              text: 'Browser market share, April, 2011'
          },
          subtitle: {
              text: 'Click the columns to view versions. Click again to view brands.'
          },
          legend:{
              enabled:false
          },
          xAxis: {
              categories: categories
          },
          yAxis: {
              title: {
                  text: 'Total percent market share'
              }
          },
          plotOptions: {
              line: {
                  cursor: 'pointer',
                  point: {
                      events: {
                          click: function() {
                              var drilldown = this.drilldown;
                              if (drilldown) { // drill down
                                  setChart(drilldown.name, drilldown.categories, drilldown.data, drilldown.color);
                              } else { // restore
                                  setChart(name, categories, data);
                              }
                          }
                      }
                  },
                  dataLabels: {
                      enabled: true,
                      color: colors[0],
                      style: {
                          fontWeight: 'bold'
                      },
                      formatter: function() {
                          return this.y +'%';
                      }
                  }
              }
          },
          tooltip: {
              formatter: function() {
                  var point = this.point,
                      s = this.x +':&lt;b&gt;'+ this.y +'% market share&lt;/b&gt;&lt;br/&gt;';
                  if (point.drilldown) {
                      s += 'Click to view '+ point.category +' versions';
                  } else {
                      s += 'Click to return to browser brands';
                  }
                  return s;
              }
          },
          series: [{
              name: name,
              data: data
          }],
          exporting: {
              enabled: false
             }
        });
    });
  
  });
  </code></pre>