react-native-SubmissionsReducer.js

import ActionTypes from '../constants/ActionTypes';

let SubmissionsReducer = (state = {}, action) => {
  let newState;

  switch (action.type) {
  case ActionTypes.RECEIVE_SUBMISSIONS_LIST:
    newState = {};
    action.submissions.forEach((s) => {
      newState[s.id] = s;
    });
    return newState;
  default:
    return state;
  }
};

export default SubmissionsReducer;