echarts map设置背景图片

       `  {
          map: name,
          roam: false,
          zoom: 1,
          layoutSize: this.height,
          layoutCenter: ['30%', '43%'],
          itemStyle: {
            color: {
              image: this.bg,      //设置背景图片
              repeat: 'no-repeat' // 是否平铺，可以是 'repeat-x', 'repeat-y', 'no-repeat'
            }
          },
          label: {
            show: false
          },
          zlevel: 3,
          silent: true
        },`