多X轴折线echarts category配置项内容和展示

      var colors = ['#5793f3', '#d14a61', '#675bba'];


option = {
    color: colors,

    tooltip: {
        trigger: 'none',
        axisPointer: {
            type: 'cross'
        }
    },
    legend: {
        data:['2015 降水量', '2016 降水量', '2017 降水量']
    },
    grid: {
        top: 70,
        bottom: 80
    },
    xAxis: [
        {
            type: 'category',
            position:'bottom',
            axisTick: {
                alignWithLabel: true
            },
            axisLine: {
                onZero: false,
                lineStyle: {
                    color: colors[1]
                }
            },
            axisPointer: {
                label: {
                    formatter: function (params) {
                        return '降水量  ' + params.value
                            + (params.seriesData.length ? '：' + params.seriesData[0].data : '');
                    }
                }
            },
            data: ['2016-1', '2016-2', '2016-3', '2016-4', '2016-5', '2016-6', '2016-7', '2016-8', '2016-9', '2016-10', '2016-11', '2016-12', '2016-10', '2016-11', '2016-12']
        },
        {
            type: 'category',
            position:'bottom',
            offset:20,
            axisTick: {
                alignWithLabel: true
            },
            axisLine: {
                onZero: false,
                lineStyle: {
                    color: colors[0]
                }
            },
            axisPointer: {
                label: {
                    formatter: function (params) {
                        return '降水量  ' + params.value
                            + (params.seriesData.length ? '：' + params.seriesData[0].data : '');
                    }
                }
            },
            data: ['2015-1', '2015-2', '2015-3', '2015-4', '2015-5', '2015-6', '2015-7', '2015-8', '2015-9', '2015-10', '2015-11', '2015-12', '2016-10', '2016-11', '2016-12']
        },
        {
            type: 'category',
            position:"bottom",
            offset:40,
            axisTick: {
                alignWithLabel: true
            },
            axisLine: {
                onZero: false,
                lineStyle: {
                    color: colors[2]
                }
            },
            axisPointer: {
                label: {
                    formatter: function (params) {
                        return '降水量  ' + params.value
                            + (params.seriesData.length ? '：' + params.seriesData[0].data : '');
                    }
                }
            },
            data: ['2015-1', '2015-2', '2015-3', '2015-4', '2015-5', '2015-6', '2015-7', '2015-8', '2015-9', '2015-10', '2015-11', '2015-12', '2016-10', '2016-11', '2016-12']
        }
    ],
    yAxis: [
        {
            type: 'value'
        }
    ],
    series: [
        {
            name: '2015 降水量',
            type: 'line',
            xAxisIndex: 0,
            smooth: true,
            data: [2.6, 5.9, 9.0, 26.4, 28.7, 70.7, 175.6, 182.2, 48.7, 18.8, 6.0, 2.3,"","",""]
        },
        {
            name: '2016 降水量',
            type: 'line',
            xAxisIndex: 1,
            smooth: true,
            data: [3.9, 5.9, 11.1, 18.7, 48.3, 69.2, 231.6, 46.6, 55.4, 18.4, 10.3, 0.7,7,8,6]
        },
        {
            name: '2017 降水量',
            type: 'line',
            xAxisIndex: 2,
            smooth: true,
            data: [13.9, 7.9, 5.1, 18.7, 18.3, 19.2, 31.6, 41.6, 55.4, 18.4, 10.3, 1.7,17,8,26]
        }
    ]
};