new echarts.graphic.LinearGradient怎么引入

在Vue中使用ECharts时，需要先安装ECharts并在组件中引入。在引入ECharts后，可以通过this.$echarts来访问ECharts的API。要使用new echarts.graphic.LinearGradient，需要在组件中先引入graphic模块。可以在组件中这样写：

import echarts from 'echarts/lib/echarts'
import 'echarts/lib/component/tooltip'
import 'echarts/lib/component/title'
import 'echarts/lib/component/legend'
import 'echarts/lib/chart/line'
import 'echarts/lib/chart/bar'
import 'echarts/lib/chart/pie'
import 'echarts/lib/chart/scatter'
import 'echarts/lib/chart/radar'
import 'echarts/lib/chart/map'
import 'echarts/lib/chart/treemap'
import 'echarts/lib/chart/graph'
import 'echarts/lib/chart/gauge'
import 'echarts/lib/chart/funnel'
import 'echarts/lib/chart/parallel'
import 'echarts/lib/chart/sankey'
import 'echarts/lib/chart/boxplot'
import 'echarts/lib/chart/candlestick'
import 'echarts/lib/chart/effectScatter'
import 'echarts/lib/chart/lines'
import 'echarts/lib/chart/heatmap'
import 'echarts/lib/chart/pictorialBar'
import 'echarts/lib/chart/themeRiver'
import 'echarts/lib/chart/sunburst'
import 'echarts/lib/chart/custom'
import 'echarts/lib/component/graphic'

export default {
  data() {
    return {
      chartData: {}
    }
  },
  mounted() {
    this.initChart()
  },
  methods: {
    initChart() {
      const chartDom = this.$refs.chart
      const myChart = echarts.init(chartDom)
      // 在这里使用new echarts.graphic.LinearGradient
      const gradient = new this.$echarts.graphic.LinearGradient(0, 0, 0, 1, [{
        offset: 0,
        color: '#00aaff'
      }, {
        offset: 0.7,
        color: '#998866'
      }, {
        offset: 1,
        color: '#998866'
      }])
      // 在这里使用gradient
      myChart.setOption({
        backgroundColor: gradient,
        ...
      })
      this.chartData = myChart
    }
  }
}

这样就可以在Vue组件中使用new echarts.graphic.LinearGradient了。