barecharts 柱状配置项内容和展示

      option = {
    backgroundColor:'#000000',
    legend: {},
    tooltip: {},
    dataset: {
        source: [
            ['product', '2015', '2016', '2017'],
            ['Matcha Latte', 43.3, 85.8, 93.7],
            ['Milk Tea', 83.1, 73.4, 55.1],
            ['Cheese Cocoa', 86.4, 65.2, 82.5],
            ['Walnut Brownie', 72.4, 53.9, 39.1]
        ]
    },
    xAxis: {type: 'category'},
    yAxis: {},
    series: [
        
        {type: 'bar',barGap:'-30%'},
        {type: 'bar',barGap:'-30%'},
        {type: 'bar',barGap:'-30%'}
    ]
};