testItemId为后台返回匹配图标的变量名 

sportsTargetsData:{
  suggestSportTargetId: "2",
  unlocks: [{ testItemId: 'vo2max_high_knee', sportTargetName: '心肺能力', indexName: '心肺能力', sportTargetId: '1' },
  { testItemId: 'grip_strength', sportTargetName: '基础力量', indexName: '基础力量', sportTargetId: '1' },
  { testItemId: 'hwbc_jz', sportTargetName: '减脂', indexName: '减脂', sportTargetId: '2' },
  { testItemId: 'hwbc_zj', sportTargetName: '增肌', indexName: '增肌', sportTargetId: '3' },
  { testItemId: 'oneleg_stand', sportTargetName: '平衡性', indexName: '平衡性', sportTargetId: '4' },
  { testItemId: 'vertical_jump', sportTargetName: '爆发力', indexName: '爆发力', sportTargetId: '5' },],
  locks: [
    { testItemId: 'reaction_duration', sportTargetName: '灵敏性', indexName: '跳绳', sportTargetId: '1' },
    { testItemId: 'body_bend', sportTargetName: '柔韧性', indexName: '卷腹', sportTargetId: '2' },
    { testItemId: 'pushup_situp', sportTargetName: '肌肉耐力', indexName: '哑铃', sportTargetId: '3' },
  ]
} ,//接口数据

图标命名：

html:

      <block wx:for="{{ sportsTargetsData.unlocks }}" wx:key="index">
        <view class="sports-goals-item {{ index==activeIdx ? ' targetActive' : '' }}" catchtap="changeTarget" data-index="{{ index }}">
        <!-- 图标直接使用item.testItemId -->
          <image class="sports-goals-item-img" src="/static/image/sports/{{ index === activeIdx ? 'active_' + item.testItemId : item.testItemId }}.png" mode="" />
          <view class="sports-goals-item-text">
            {{ item.sportTargetName }}
          </view>
        </view>
      </block>