echars环形图中间添加文字

option = {
   
    tooltip: {
        trigger: 'item',
        formatter: "{a} 
{b}: {c} ({d}%)"
    },
    legend: {
        orient: 'vertical',
        x: 'left',
        data:['直接访问','邮件营销','联盟广告','视频广告','搜索引擎']
    },
     graphic: [{ //环形图中间添加文字
            type: 'text', //通过不同top值可以设置上下显示
            left: 'center',
            top: '45%',
            style: {
                text: '环图中添加颜色'+'\n'+'和series平级',
                textAlign: 'center',
                fill: 'blue', //文字的颜色
                width: 30,
                height: 30,
                fontSize: 20,
                fontFamily: "Microsoft YaHei"
            }
        }],
    series: [
        {
            name:'访问来源',
            type:'pie',
            radius: ['50%', '70%'],
            avoidLabelOverlap: false,
            label: {
                normal: {
                    show: false,
                    position: 'center'
                },
                emphasis: {
                    show: true,
                    textStyle: {
                        fontSize: '30',
                        fontWeight: 'bold'
                    }
                }
            },
            labelLine: {
                normal: {
                    show: false
                }
            },
            data:[
                {value:335, name:'直接访问'},
                {value:310, name:'邮件营销'},
                {value:234, name:'联盟广告'},
                {value:135, name:'视频广告'},
                {value:1548, name:'搜索引擎'}
            ]
        }
    ]
};