Reactjs 如果selectedItem redux状态将被其他组件使用，那么我将选择选项2，否则选择选项4。我目前也有类似的问题，您最终使用了哪个选项？我目前正在使用选项2。但是选项2会一直有效吗？我的印象是componentWillReceiveProps仅在道具

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如果selectedItem redux状态将被其他组件使用，那么我将选择选项2，否则选择选项4。我目前也有类似的问题，您最终使用了哪个选项？我目前正在使用选项2。但是选项2会一直有效吗？我的印象是componentWillReceiveProps仅在道具更改时运行，而不一定在第一次渲染时运行。因此，如果您的道具没有发生变化，这个生命周期方法将不会运行，您的操作也不会被调度。不过，也许我误解了该生命周期方法的语义。@AdamDonahue React文档清楚地指出：注意，即使道具没有更改，React也可能调用此方法，因此，如果您只想处理更改，请确保比较当前值和下一个值。当父组件导致组件重新渲染时，可能会发生这种情况@我想你误解了。我的意思是，如果您的初始道具集从未更改，那么componentWillReceiveProps可能无法运行。至少，这是我对该生命周期方法文档的以下部分的解释：“React不会在装载期间使用初始道具调用componentWillReceiveProps。它只会在某些组件道具可能更新时调用此方法。”显然，上面的选项2是不完整的。或者可以，除非你以某种方式强制改变道具。

const fetchList = graphql(
  dataListQuery, {
    options: ({ listId }) => ({
      variables: {
        listId,
      },
    }),
    props: ({ data: { loading, dataList } }) => {
      return {
        loading,
        list: dataList,
      };
    }
  }
);

const enhance = compose(
  connect(
    function mapStateToProps(state) {
      return {
        selectedItem: getSelectedItem(state),
      };
    }, {
      selectItem, // action creator
    }
  ),
  graphql(
    dataListQuery, {
      options: ({ listId }) => ({
        variables: {
          listId,
        },
      }),
      props: ({ data: { loading, dataList } }) => ({
        loading,
        items: dataList,
      }),
    }
  ),
  lifecycle({
    componentWillReceiveProps(nextProps) {
      const {
        loading,
        items,
        selectedItem,
        selectItem,
      } = nextProps;
      if (!selectedItem && !loading && items && items.length) {
        selectItem(items[items.length - 1].id);
      }
    }
  })
);

class yourComponent extends Component{
    componentWillReceiveProps(nextProps) {
      const {
        loading,
        items,
        selectedItem,
        selectItem,
      } = nextProps;
      if (!selectedItem && !loading && items && items.length) {
        selectItem(items[items.length - 1].id);
      }
    }
  render(){...}
}

// Connect redux and graphQL to the Component
const yourComponentWithGraphQL = graphql(...)(yourComponent);
export default connect(mapStateToProps, mapDispatchToProps)(yourComponentWithGraphQL)

const enhance = compose(
  connect(
    function mapStateToProps(state) {
      return {
        selectedItem: getSelectedItem(state),
      };
    }, {
      selectItem, // action creator
    }
  ),
  graphql(
    dataListQuery, {
      options: ({ listId }) => ({
        variables: {
          listId,
        },
      }),
      props: ({ data: { loading, dataList } }) => {
        if (!loading && dataList && dataList.length) {
          selectItem(dataList[dataList.length - 1].id);
        }
        return {
          loading,
          items: dataList,
        }
      },
    }
  ),
);

componentDidUpdate(prevProps, prevState) {

    if (this.props.data !== prevProps.data) {
        dispatch some action that set whatever you need to set
    }
}

const enhance = compose(
    connect(),
    graphql(dataListQuery, {
      options: ({ listId }) => ({
        variables: {
          listId,
        },
      }),
      props: ({ data: { loading, dataList } }) => ({
        isLoading:loading,
        isData:!!dataList,
        dataList
       }),
    }
  ),
withLoader
)(Component)

    function withLoader(WrappedComponent) {
        class comp extends React.PureComponent {
           render(){
              return this.props.isData?<WrappedComponent {...this.props}/>:<Loading/>
           }
        }
    }

export default compose(
  connect(
    state => ({ /* ... */ }),
    dispatch => ({ 
      someReduxAction: (payload) => dispatch({ /* ... */ }),
      anotherReduxAction: (payload) => dispatch({ /* ... */ }),
    }),
  ),
  graphqlWithDone(someQuery, {
    name: 'someQuery',
    options: props => ({ /* ... */ }),
    props: props => ({ /* ... */ }),
    makeDone: props => dataFromQuery => props.someReduxAction(dataFromQuery)
  }),
  graphqlWithDone(anotherQuery, {
    name: 'anotherQuery',
    options: props => ({ /* ... */ }),
    props: props => ({ /* ... */ }),
    makeDone: props => dataFromQuery => props.anotherReduxAction(dataFromQuery)
  })
)(SomeComponent)

const graphqlWithDone = (query, queryConfig) => (Wrapped) => {

  const enhance = graphql(query, {
    ...queryConfig,
    props: (props) => ({
      queryData: { ...( props[queryConfig.name] || props.data ) },
      queryProps: queryConfig.props(props),
    })
  })

  class GraphQLWithDone extends Component {
    state = {
      isDataHandled: false
    }

    get wrappedProps () {
      const resultProps = { ...this.props };
      delete resultProps.queryData;
      delete resultProps.queryProps;
      return {  ...resultProps, ...this.props.queryProps }
    }

    get shouldHandleLoadedData () {
      return (
        !this.props.queryData.error &&
        !this.props.queryData.loading &&
        !this.state.isDataHandled
      )
    }

    componentDidUpdate() {
      this.shouldHandleLoadedData &&
      this.handleLoadedData(this.props.queryData);
    }

    handleLoadedData = (data) => {
      if (!makeDone || !isFunction(makeDone)) return;
      const done = makeDone(this.wrappedProps)
      this.setState({ isDataHandled: true }, () => { done(data) })
    }

    render() {
      return <Wrapped {...this.wrappedProps}  />
    }
  }

  return enhance(GraphQLWithDone)
}