解决方法深拷贝一下需变动的数组，因为如果不拷贝map改变了数组(数组里的元素为引用类型)，而react禁止改变props

  getOnlineData = (roommates, onlineRoommates) => {
    const newRoommates =JSON.parse(JSON.stringify(roommates))
    return (newRoommates.map(item => {
      onlineRoommates.map(element => {
        if (`${item.user_type}:${item.user_id}` === element.userId) {
          item.isOnline = true
          item.hasVideo = element.hasVideo
          item.hasAudio = element.hasAudio
        }
      })
      return this.renderItem(item)
    }))
  }
  render () {
    const { roommates, onlineRoommates } = this.props
 
    return (
      <div className={styles.container}>
        {this.getOnlineData(roommates, onlineRoommates)}
      </div>
    )
  }