// 官方
 constructor(props) {
  super(props);
  ...
  const dataSource = new ListView.DataSource({
   ...
   rowHasChanged: (row1, row2) => row1 !== row2 // 这个方法
  });
 }

// !!!这样写
rowHasChanged: ( row1, row2) => true

class Message extends React.Component {
 constructor(props) {
  super(props);
  const dataSource = new ListView.DataSource({
  // 这样写，每次都执行rowHasChanged,每次都更新row
   rowHasChanged: ( row1, row2) => true
  });

  this.state = {
   dataSource,
  };
 }

 componentDidMount() {
  // 请求初始化数据
 }

 // 在这里维护长列表数据，把从接口获取来的数据赋值给state里的dataSource。
 componentWillReceiveProps(nextProps) {
  if(nextProps.message.commentList !== this.props.message.commentList){
   this.setState({
   // 注意！这里的cloneWithRows()，antd里规定用它来更新dataSource，这个不是拼接数据，用这个函数，dataSource会更新成nextProps.message.commentList。
   //所以在接受后端分页数据时，就把拼接好的数据赋值给nextProps.message.commentList（这个在model.js里写了）
    dataSource: this.state.dataSource.cloneWithRows(nextProps.message.commentList),
   });
  }
 }

// onEndReached,列表被滚动到距离最底部不足`onEndReachedThreshold`个像素的距离时调用
// 在这里写分页请求
 onEndReached = (event) => {
  const { dispatch } = this.props;
  const { email } = this.props.user;
  const { pageNum, pageSize, contentId, totalCount, commentList } = this.props.message;
  
  let hasMore = totalCount > commentList.length "message/updateStates",
   payload: {
    pageNum: pageNum+1,
    isLoading: true,
    isLongList: true
   }
  })
  setTimeout(() => {
   dispatch({
    type: "message/getCommentsByContentId",
    payload: {
     contentId,
     identity: email, 
     pageNum: pageNum+1,
     pageSize
    }
   })
  }, 1000);
 }

 render() {
 // 列表的item
  const row = (rowData, sectionID, rowID) => {
   const item = rowData;
   return (
    <div className={styles.item} key={rowID}>
      <div onClick={toggleLike}>点赞</div>
      <div className={styles.content}>{item.content}</div>
      </div>
    </div>
   );
  };

  return (
   <Fragment>
     <ListView
     ref={el => this.lv = el}
     dataSource={this.state.dataSource}
     renderHeader={() => (
      <div className={styles.sub}>
       <span>列表头，什么写点什么</span>
      </div>
     )}
     renderFooter={() => (<div style={{ padding: 10, textAlign: 'center' }}>
      { isLoading "am-list"
     pageSize={pageSize}
     useBodyScroll
     scrollRenderAheadDistance={500}
     onEndReached={this.onEndReached}
     onEndReachedThreshold={10}
    />
   </Fragment>
  );
 }
}

*getCommentsByContentId({ payload }, { call, put, select }) {
   const { data } = yield call(getCommentsByContentId, payload);
   const { message } = yield select(state=>state);
   const { commentList } = message;
   if (data.code === 200) {
    // 长列表，上一次页的数据+这次的数据，赋值给新的commentList
    let list = [...commentList, ...data.data.list]
    yield put({
     type: 'updateStates',
     payload: {
      totalCount: data.data.totalCount,
      commentList: list
     }
    });
   } else {
    Toast.fail(data.msg, 1)
   }
  },