DropdownAlert.js

import React from 'react'
import DropdownAlert from 'react-native-dropdownalert'
import DropdownAlertReduxActions from '../Redux/DropdownAlertRedux'
import I18n from 'react-native-i18n'
import { Colors } from '../Themes'
import { connect } from 'react-redux'

class Dropdown extends React.Component {
  dropdown: DropdownAlert

  componentWillReceiveProps ({alert}) {
    if (!alert) {
      return
    }

    this.dropdown.alertWithType(alert.type, I18n.t(alert.title), I18n.t(alert.message))
  }

  alertClosed () {
    this.props.clear()
  }

  render () {
    const {alert} = this.props

    return (
      <DropdownAlert
        warnColor={Colors.primaryYellow}
        errorColor={Colors.primaryRed}
        successColor={Colors.primaryGreen}
        ref={ref => { this.dropdown = ref }}
        closeInterval={(alert && alert.closeInterval) || 2500}
        onClose={() => this.alertClosed()}
      />
    )
  }
}

const mapStateToProps = (state) => {
  return {
    alert: state.dropdownAlert.alert
  }
}

const mapDispatchToProps = (dispatch) => {
  return {
    clear: () => dispatch(DropdownAlertReduxActions.clearAlert())
  }
}

export default connect(mapStateToProps, mapDispatchToProps)(Dropdown)

DropdownAlertRedux.js

import { createActions, createReducer } from 'reduxsauce'
import Immutable from 'seamless-immutable'

/* ------------- Types and Action Creators ------------- */
const {Types, Creators} = createActions({
  alertError: ['title', 'message', 'closeInterval'],
  alertInfo: ['title', 'message', 'closeInterval'],
  alertWarn: ['title', 'message', 'closeInterval'],
  alertSuccess: ['title', 'message', 'closeInterval'],
  clearAlert: null
})

export const DropdownAlertTypes = Types
export default Creators

/* ------------- Initial State ------------- */

export const INITIAL_STATE = Immutable({alert: null})

export const log = (state, type, {title, message}) => Immutable({alert: {title, message, type}})
export const error = (state, action) => log(state, 'error', action)
export const info = (state, action) => log(state, 'info', action)
export const warn = (state, action) => log(state, 'warn', action)
export const success = (state, action) => log(state, 'success', action)
export const clear = () => INITIAL_STATE

/* ------------- Hookup Reducers To Types ------------- */

export const reducer = createReducer(INITIAL_STATE, {
  [Types.ALERT_ERROR]: error,
  [Types.ALERT_INFO]: info,
  [Types.ALERT_WARN]: warn,
  [Types.ALERT_SUCCESS]: success,
  [Types.CLEAR_ALERT]: clear
})

using.md

In Containers/RootContainer.js add:

<Dropdown />