handleOriginCurrencyChange(event) {
    var newCurrency = event.target.value;
    this.props.dispatch(actions.changeOriginCurrency(newCurrency));

    // will the dispatch above affects `this.props`?
    // cause I think the dispatch will trigger the update
    var payload = {
      originAmount: this.props.originAmount,
      originCurrency: newCurrency,
      destCurrency: this.props.destinationCurrency,
      calcOriginAmount: false,
    };


    // this one is a async ajax dispatch,
    // will the function stop here
    // when resolve then continue the func
    // finally do the last diapatch?
    this.props.dispatch(actions.fetchConversionRate(payload));

    var feePayload = {
      originAmount: this.props.originAmount,
      originCurrency: newCurrency,
      destCurrency: this.props.destinationCurrency,
    };

    this.props.dispatch(actions.fetchFees(feePayload));
  }