title: Multiple series in Highcharts with multiple drilldowns
body: <p>I found <a href="http://jsfiddle.net/highcharts/kh5jY/" rel="nofollow">this</a> example, however I'm struggling to make it work with two series together. </p>
  
  <p>I want to have two series, each of which are drilled down to two series when we drilldown on either of the parent series. </p>
  
  <p>If I don't put in the drilldown categories for each point, I get only one series when I drill down.· If I add the drilldowns to each point as each series as the example suggests, I get nothing displayed. </p>
  
  <pre><code>        for cluster in models.Cluster.objects.all():
          qd = self.clone_query_dict()
          qd['cluster'] = cluster.id
          drilldown = {'categories': [x.name for x in get_countries().filter(
              client_clusters=cluster,
          )]}
          drilldown.update(self.drilldown_by_cluster(cluster))
          site_numbers_data.append(self.get_datum(
              qd,
              cluster.name,
              drilldown=drilldown,
          )
          avg_risk_data.append(self.get_datum(
              qd,
              cluster.name,
              drilldown=drilldown,
              avg='avg_field',
          ))
  </code></pre>
  
  <p>I'm constructing the JSON with Python:</p>
  
  <pre><code>for child in parent:
  </code></pre>
  
  <p>The code I'm templating off:</p>
  
  <pre><code>$(function () {
  var chart;
  $(document).ready(function() {
  
      var colors = Highcharts.getOptions().colors,
          categories = ['MSIE', 'Firefox', 'Chrome', 'Safari', 'Opera'],
          name = ['Browser brands'],
          data = [{
                  y: 55.11,
                  color: colors[0],
                  drilldown: {
                      categories: ['MSIE 6.0', 'MSIE 7.0', 'MSIE 8.0', 'MSIE 9.0'],
                      series: [{
                          type: 'spline',
                          name: 'MSIE versions 2000',
                          data: [10.85, 7.35, 33.06, 2.81],
                          color: colors[0]
                      },{
                          type: 'column',
                          name: 'MSIE versions 2010',
                          data: [1, 5, 10, 15],
                          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]
                  }
              }];
  
      function setChart(name, categories, data, color, type) {
          var len = chart.series.length;
          chart.xAxis[0].setCategories(categories);
          for(var i = 0; i &lt; len; i++){
              console.log(chart.series.length);
              chart.series[0].remove();
          }
          console.log('a');
          if(data.series){
              for(var i = 0; i &lt; data.series.length; i ++ ){
                  chart.addSeries({
                      name: data.series[i].name,
                      data: data.series[i].data,
                      type: data.series[i].type,
                      color: data.series[i].color || 'white'
                  });
              }
          } else {
                  chart.addSeries({
                      name: name,
                      data: data,
                      type: type,
                      color: color || 'white'
                  });
          }
      }
  
      chart = new Highcharts.Chart({
          chart: {
              renderTo: 'container',
              type: 'column'
          },
          title: {
              text: 'Browser market share, April, 2011'
          },
          subtitle: {
              text: 'Click the columns to view versions. Click again to view brands.'
          },
          xAxis: {
              categories: categories
          },
          yAxis: {
              title: {
                  text: 'Total percent market share'
              }
          },
          plotOptions: {
              column: {
                  cursor: 'pointer',
                  point: {
                      events: {
                          click: function() {
                              var drilldown = this.drilldown;
                              if (drilldown) { // drill down
                                  setChart(null, drilldown.categories, drilldown, drilldown.type);
                              } else { // restore
                                  setChart(name, categories, data, drilldown.type);
                              }
                          }
                      }
                  },
                  dataLabels: {
                      enabled: true,
                      color: colors[0],
                      style: {
                          fontWeight: 'bold'
                      },
                      formatter: function() {
                          return this.y +'%';
                      }
                  }
              },
              spline: {
                  cursor: 'pointer',
                  point: {
                      events: {
                          click: function() {
                              setChart(name, categories, data, 'column');
                          }
                      }
                  },
                  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,
              color: 'white'
          }],
          exporting: {
              enabled: false
          }
      });
  });
  </code></pre>
  
  <p>});</p>