let myPieChart = echarts.init(document.getElementById('pies'))
if (data.length == 0) {
  myPieChart.clear()
  myPieChart.setOption({
    title: {
      text: '暂无数据',
      x: 'center',
      y: 'center',
      textStyle: {
        fontSize: 12,
        color: '#909399',
        fontWeight: 'normal'
      }
    }
  })
} else {
  myPieChart.setOption({
    title: {
      show: false
    }
  })
}