课程代码已对react-navigation-redux-helpers3.0做了适配：

• 24212eb835 - Keep react navigation new and react-navigation-redux-helpe : 此次更新适配了react-navigation-redux-helpers3.0;

react-navigation-redux-helpers3.0的两个变更:

1.reduxifyNavigator被改名为createReduxContainer，所以：

import {createReactNavigationReduxMiddleware, reduxifyNavigator} from 'react-navigation-redux-helpers';
//改为
import {createReactNavigationReduxMiddleware, createReduxContainer} from 'react-navigation-redux-helpers';
...
const AppWithNavigationState = reduxifyNavigator(RootNavigator, 'root');
//改为
const AppWithNavigationState = createReduxContainer(RootNavigator, 'root');

2.createReactNavigationReduxMiddleware的参数顺序发生了变化：

export const middleware = createReactNavigationReduxMiddleware(
    'root',
    state => state.nav
);
//改为
export const middleware = createReactNavigationReduxMiddleware(
    state => state.nav,
    'root'
);

可参考：https://git.imooc.com/coding-304/GitHub_Advanced/commit/24212eb835b6db639b82017b8090c15a14dea48f