Sencha touch 2 Sencha Touch 2饼图没有标签

我尝试按照示例创建饼图，但我的图表不显示各部分的标签。我复制并使用了上面链接的示例中的精确代码

图表显示完整的颜色部分，但没有像示例中那样的标签

我的代码粘贴在下面：

    Ext.define('RevivalTimes.view.Chart', {
        extend: 'Ext.chart.PolarChart',
        xtype: 'chart',

        requires: [
            'Ext.chart.series.Pie',
            'Ext.chart.interactions.Rotate'
        ],

        config: {
            title: 'Statistics',
            iconCls: 'settings',

            layout: 'fit',

            animate: true,
            interactions: ['rotate'],
            colors: ['#115fa6', '#94ae0a', '#a61120', '#ff8809', '#ffd13e'],
            store: {
              fields: ['name', 'data1', 'data2', 'data3', 'data4', 'data5'],
              data: [
                  {name: 'metric one',   data1: 10, data2: 12, data3: 14, data4: 8,  data5: 13},
                  {name: 'metric two',   data1: 7,  data2: 8,  data3: 16, data4: 10, data5: 3},
                  {name: 'metric three', data1: 5,  data2: 2,  data3: 14, data4: 12, data5: 7},
                  {name: 'metric four',  data1: 2,  data2: 14, data3: 6,  data4: 1,  data5: 23},
                  {name: 'metric five',  data1: 27, data2: 38, data3: 36, data4: 13, data5: 33}
              ]
            },
            series: [{
                type: 'pie',
                label: {
                    field: 'name',
                    display: 'rotate'
                },
                xField: 'data3',
                donut: 30
            }]

        } //config
    });

---

标签显示时包含labelField，如下代码所示：

series: [{
    type: 'pie',
    label: {
        field: 'name',
        display: 'rotate'
    },
    xField: 'data1',
    donut: 30,

    labelField: 'name',
    showInLegend: true,
}],