<template>
  <div>
    <v-chart :forceFit="true" :height="height" :data="data">
      <v-tooltip />
      <v-axis />
      <v-legend />
      <v-bar position="月份*月均降雨量" color="name" :adjust="adjust" />
    </v-chart>
  </div>
</template>

<script>
  const DataSet = require('@antv/data-set');

  const sourceData = [
    { name: 'London', 'Jan.': 18.9, 'Feb.': 28.8, 'Mar.': 39.3, 'Apr.': 81.4, 'May': 47, 'Jun.': 20.3, 'Jul.': 24, 'Aug.': 35.6 },
    { name: 'Berlin', 'Jan.': 12.4, 'Feb.': 23.2, 'Mar.': 34.5, 'Apr.': 99.7, 'May': 52.6, 'Jun.': 35.5, 'Jul.': 37.4, 'Aug.': 42.4 },
  ];

  const dv = new DataSet.View().source(sourceData);
  dv.transform({
    type: 'fold',
    fields: ['Jan.', 'Feb.', 'Mar.', 'Apr.', 'May', 'Jun.', 'Jul.', 'Aug.'],
    key: '月份',
    value: '月均降雨量',
  });
  const data = dv.rows;

  export default {
    data() {
      return {
        data,
        height: 400,
        adjust: [{
          type: 'dodge',
          marginRatio: 1 / 32,
        }],
      };
    }
  };
</script>