title: Action Creators Undefined
body: <p>I'm new to redux, and I'm trying to update my app's state by dispatching the action creator function fetching() in my container file. When I try running my app, I get a "Cannot read property 'fetching' of undefined" error. Why is that?</p>
  
  <pre><code>//popular reducer
  const FETCHING = 'FETCHING'
  
  export function fetching() {
    return {
      type: FETCHING,
    }
  }
  
  const initialState = {
    isFetching: false,
  }
  
  export default function popular(state = initialState, action) {
    switch (action.type) {
      case FETCHING:
        return {
          isFetching: true,
        }
      default:
        return state
    }
  }
  
  //Popular Container
  import { bindActionCreators } from 'redux'
  import { connect } from 'react-redux'
  import * as popularActionCreators from 'redux/popular'
  import PropTypes from 'prop-types'
  
  class PopularContainer extends React.Component {
  
    handleFetch() {
      this.props.fetching() //Cannot read property 'fetching' of undefined
    }  
  }
  
  PopularContainer.propTypes = {
    isFetching: PropTypes.bool.isRequired,
    fetching: PropTypes.func.isRequired,
  }
  
  function mapStateToProps(state) {
    return {
      isFetching: state.isFetching
    }
  }
  
  function mapDispatchToProps(dispatch) {
    return bindActionCreators(popularActionCreators, dispatch)
  }
  
  export default connect(
    mapStateToProps,
    mapDispatchToProps
  )(PopularContainer)
  </code></pre>