title: Legend not updating
body: <p>I seem to be having a problem with the legend udating</p>
  
  <p>When the data changes in the stor the pie chart updates but the legend does not.</p>
  
  <p>But to surprise its getting updated once when we reset the pie chart, as am using Reset option in interactions.</p>
  
  <p>I don't know what the exact problem why legend is not updating first time itself.</p>
  
  <p>when I use hard code values for the store then legend was getting updated at the first itself. For the dynamic values only the legend was not updating intially.</p>
  
  <p>Please refer Some part of my code,</p>
  
  <pre><code>    PieChart = new Ext.chart.Chart( {
  
                                 cls: 'pie1',
  
                                 theme: 'Demo',
  
                                 store: store1
                                 shadow: true,
  
                                 animate: true,
  
     legend: {
       position: 'top'
  
      //  dock: false
  },
     interactions: [ {
  
                     type: 'reset',
                    confirm: true
                    }],
  
  
  series:
      [ {
  
          type: 'pie',
  
          renderer: function(sprite, storeItem, barAttr, m, store11) {
  
              barAttr.fill = colors1[m % colors1.length];
  
              return barAttr;
  
          },
  
          field: 'data1',
  
          showInLegend: true,
  
          highlight: false,
  
          donut: 15,
  
          listeners: {
  
              'labelOverflow': function(label, item) {
  
                  item.useCallout = true;
  
              }
  
          },
  
          callouts: {
  
              renderer: function(callout, storeItem) {
  
                  callout.label.setAttributes( {
  
                      text: storeItem.get('Horizontal')
  
                  }, true);
  
              },
  
              filter: function() {
  
                  return false;
  
              },
  
              box: {
  
                  //no config here.
  
              },
  
              lines: {
  
                  'stroke-width': 2,
  
                  offsetFromViz: 10
  
              },
  
              label: {
  
                  font: 'italic 14px Arial'
  
              },
  
              styles: {
  
                  font: '14px Arial'
  
              }
  
          },
  
          label: {
  
              field: 'Horizontal',
  
              display: 'rotate',
  
              font: '5px Arial'
  
          }
  
      }]
  </code></pre>
  
  <p>Any ideas?</p>