实现效果：

index.json文件：

{
    "component": true,
    "usingComponents": {
        "ec-canvas":"../../components/ec-canvas/ec-canvas"
    }
}

index.wxss 文件：

 <view class="pie-charts">
  <view class="lengendTitle">
  <image src="{{tipImg}}" class="tipLineImg" />
  <text class="tipTitle">时/分</text>
  </view>
    <ec-canvas
      id="mychart-dom-bar"
      canvas-id="mychart-bar"
      ec="{{ ec }}"
    ></ec-canvas>
  </view>

inex.js 文件配置：

import * as echarts from '../ec-canvas/echarts';
function initChart(canvas, width, height) {
  const chart = echarts.init(canvas, null, {
    width: width,
    height: height
  });
  canvas.setChart(chart);

  var option = {
    grid: {
      show: false,
      top: '9%',
      right: '5%',
      left: '10%'
    },
    xAxis: {
      type: 'category',
      axisLine: {
        show: true,
        lineStyle: {
          type: "dashed"
        }
      },
      data: ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '10', '11', '12', '13', '14']
    },
    yAxis: {
      type: 'value',
      splitLine: {
        show: false,
      },
      axisLine: {
        show: true,
        lineStyle: {
          type: "dashed"
        }
      }
    },
    series: [{
      data: [0, 40, 10, 40, 25, 60, 40, 10, 60, 25, 0, 40, 10, 40, 25],
      type: 'line',
      smooth: true,
      itemStyle: {
        normal: {
          color: '#ffb71b',
          lineStyle: {        // 系列级个性化折线样式  
            width: 4,
            type: 'solid',
            color: new echarts.graphic.LinearGradient(0, 0.4, 0.7, 1, [{
              offset: 0,
              color: '#ffb71b'
            } , {
              offset: 0.4,
              color: '#b75cee'
            }, {
              offset: 0.7,
              color: '#66acfc'
            }, {
              offset: 1,
            color: '#3843fa'
          }]),//线条渐变色  
          }
        },
      }
    }]
  };
  chart.setOption(option);
  return chart;
}
Component({
  /**
   * 组件的属性列表
   */
  properties: {

  },

  /**
   * 组件的初始数据
   */
  data: {
    ec: {
      onInit: initChart
    },
    tipImg: '../../img/lineTip.png'
  },

index.wxss文件：

.pie-charts {
  width: 100%;
  height: 500rpx;
  margin: 20px 0 0 10px;
}

.lengendTitle {
  display: flex;
  align-items: center;
  justify-content: center;
  padding-top: 20rpx;
}

.tipTitle {
  font-size: 28rpx;
  color: #ffffff;
  margin-left: 10rpx;
  letter-spacing: 5rpx;
}

.tipLineImg {
  width: 20rpx;
  height: 20rpx;
  padding-top: 7rpx;
}