one off actions

index.jsx

function onError (field) {
  this.refs[field].focus()
}

<Button onPress={() => this.props.register(this.state, onError)}>
  Or Register
</Button>

function register ({username, password, email}, cb) {
  return (dispatch, getState) => {
      dispatch(requestRegister())

      return fetch(API_REGISTER_URL}, {
        method: 'POST',
        headers,
        body: JSON.stringify({
          username,
          email,
          password
        })
      })
        .then(response => response.json())
        .catch(error => console.error(error.message))
        .done(json => {
          if (json.success) {
            dispatch(receiveRegister(json))
          } else if (json.data.errors.email) {
            dispatch(failRegister('Invalid email.'))
            cb('email')
          } else if (json.data.errors.username) {
            dispatch(failRegister('Invalid username.'))
            cb('username')
          }
        })
    }
  }
}