TypeError：undefined不是对象（评估'_iterator符号==='函数'？Symbol.iterator：'@@ iterator']'）

Question

我不确定导致错误的原因或解决方法。错误似乎表明它来自StudentHome组件，更具体地来说是Calendar组件。下面是StudentHome和Calendar组件，后面是错误的屏幕截图。 在此先感谢您的帮助。

StudentHome组件

import React from 'react';
import { View } from 'react-native';
import Icon from 'react-native-vector-icons/MaterialIcons';
import Calendar from './Calendar';
import StudentToolbar from './StudentToolbar';
import { MainContainer } from './common';

const navigationOptions = {
  drawerLabel: 'Home',
  drawerIcon: ({ tintColor }) =>
    <Icon name="event-note" size={24} color={tintColor} />,
};

const StudentHome = MainContainer(props => {
  return (
    <View style={{ flex: 1 }}>
      <StudentToolbar navigation={props.navigation} />
      <View style={{ flex: 1 }}>
        <Calendar />
      </View>
    </View>
  );
});

StudentHome.navigationOptions = navigationOptions;

export default StudentHome;

以下是日历组件

import { Effects, loop } from 'redux-loop';
import { NavigationActions } from 'react-navigation';
import R from 'ramda';
import CalendarHelpers from '../helpers/calendars';
import {
  LOAD_USER,
  LOAD_CALENDARS,
  LOAD_CALENDAR_EVENTS,
  CREATE_USER_EVENT,
  successActionType,
  failActionType,
} from '../actions/types';
import {
  apipost,
  showSplashLoading,
  hideSplashLoading,
  showFlashMessage,
} from '../actions';
import reducer from './builder';

const INITIAL_STATE = {
  items: {},
  error: '',
  creating: false,
};

const handlers = {
  [successActionType(LOAD_USER)]: (state, action) => ({
    ...state,
    items: action.payload.included['user-events'],
  }),

  [successActionType(LOAD_CALENDARS)]: (state, action) => {
    if (!(action.payload.included && action.payload.included['user-events'])) {
      return state;
    }

    return {
      ...state,
      items: { ...action.payload.included['user-events'] },
    };
  },

  [successActionType(LOAD_CALENDAR_EVENTS)]: (state, action) => {
    const userEvents = R.pipe(
      CalendarHelpers.getUserEventsResponse,
      R.pluck('items'),
      R.mergeAll
    )(action.payload);

    if (R.isEmpty(userEvents)) {
      return state;
    }

    return {
      ...state,
      items: { ...state.items, ...userEvents },
    };
  },

  [CREATE_USER_EVENT]: (state, action) => {
    const { resource, body } = action.payload;
    return loop(
      { ...state, creating: true, error: null },
      Effects.batch([
        Effects.constant(showSplashLoading()),
        Effects.constant(
          apipost(
            resource,
            body,
            {},
            successActionType(CREATE_USER_EVENT),
            failActionType(CREATE_USER_EVENT)
          )
        ),
      ])
    );
  },
  [successActionType(CREATE_USER_EVENT)]: (state, action) => {
    //console.warn("Printing the state");//Just the state
    //console.warn(state);
    console.warn("Printing items in state");
    console.warn(state.items);
    const event = action.payload.data;
    return loop(
      {
        ...state,
        creating: false,
        items: { ...state.items, [event.id]: event },
      },
      Effects.batch([
         Effects.constant(hideSplashLoading()),
      ])
     );
  },
  [failActionType(CREATE_USER_EVENT)]: (state, action) =>
    loop(
      { ...state, creating: false, error: action.payload },
      Effects.batch([
        Effects.constant(hideSplashLoading()),
        Effects.constant(showFlashMessage(action.payload)),
      ])
    ),
};

export default reducer(handlers, INITIAL_STATE);