attempting to setup navigation from within redux actions... buut failing... any help would be awesome

actions.js

import { NavigationActions } from 'react-navigation'

export function navIntro() {
  return function(dispatch) {
      dispatch(NavigationActions.navigate({ routeName: 'Intro' }))
  }
}

App.js

import React, { Component } from 'react';
import AppNavigator from './AppNavigator';
import { Provider } from 'react-redux';
import store from './store';

export default class App extends Component {
  render() {
    return (
      <Provider store={store}>
        <AppNavigator/>
      </Provider>
    )
  }
}

AppNavigator.js

import React from "react";
import { createRootNavigator } from "./router";
import { isSignedIn } from "./auth";

export default class AppNavigator extends React.Component {
  constructor(props) {
    super(props);

    this.state = {
      signedIn: false,
      checkedSignIn: false
    };
  }

  componentWillMount() {
    isSignedIn()
      .then(res => this.setState({ signedIn: res, checkedSignIn: true }))
      .catch(err => alert("An error occurred"));
  }

  render() {
    const { checkedSignIn, signedIn } = this.state;

    // If we haven't checked AsyncStorage yet, don't render anything (better ways to do this)
    if (!checkedSignIn) {
      return null;
    }

    const AppLayout = createRootNavigator(signedIn);
    return <AppLayout />;
  }
}

navigationReducer.js

import { createRootNavigator } from "../router";
export default (state, action) => createRootNavigator().router.getStateForAction(action, state);

router.js

import React from "react";
import { Platform, StatusBar } from "react-native";
import { StackNavigator } from 'react-navigation/lib/react-navigation.js';

import Home from "./screens/Home";
import Intro from "./screens/Intro";

const headerStyle = {
  marginTop: Platform.OS === "android" ? StatusBar.currentHeight : 0
};

export const createRootNavigator = () => {
  return StackNavigator(
    {
      Home: {
        screen: Home,
        path: '',
        navigationOptions: {
          tabBarLabel: "Home"
        }
      },
      Intro: {
        screen: Intro,
        path: '',
        navigationOptions: {
          tabBarLabel: "Home"
        }
      }
    },
    {
      headerMode: "none",
      mode: "modal",
      initialRouteName: "Home"
    }
  );
};