react-navigation/docs/guides/Redux-Integration.md
Kevin Cooper 655b46b60b Improve the Redux docs (#1172)
* [ReduxExample] Programmatically generate initial state

* [ReduxExample] Return original state if nextState is null

* [Docs] Add getStateForAction to redux integration example

* [Docs] Add link to ReduxExample app

* [Docs] Give each example a 'DRY' README linking to real docs

* [Docs] Clean up the Contributors guide a bit

* [Docs] Remove numbers from sections in Contributors guide

They don't seem very meaningful, and don't need to be done in order
2017-04-25 11:48:54 +02:00

3.1 KiB

Redux Integration

To handle your app's navigation state in redux, you can pass your own navigation prop to a navigator. Your navigation prop must provide the current state, as well as access to a dispatcher to handle navigation options.

With redux, your app's state is defined by a reducer. Each navigation router effectively has a reducer, called getStateForAction. The following is a minimal example of how you might use navigators within a redux application:

import { addNavigationHelpers } from 'react-navigation';

const AppNavigator = StackNavigator(AppRouteConfigs);

const initialState = AppNavigator.router.getStateForAction(AppNavigator.router.getActionForPathAndParams('Login'));

const navReducer = (state = initialState, action) => {
  const nextState = AppNavigator.router.getStateForAction(action, state);

  // Simply return the original `state` if `nextState` is null or undefined.
  return nextState || state;
};

const appReducer = combineReducers({
  nav: navReducer,
  ...
});

class App extends React.Component {
  render() {
    return (
      <AppNavigator navigation={addNavigationHelpers({
        dispatch: this.props.dispatch,
        state: this.props.nav,
      })} />
    );
  }
}

const mapStateToProps = (state) => ({
  nav: state.nav
});

const AppWithNavigationState = connect(mapStateToProps)(App);

const store = createStore(appReducer);

class Root extends React.Component {
  render() {
    return (
      <Provider store={store}>
        <AppWithNavigationState />
      </Provider>
    );
  }
}

Once you do this, your navigation state is stored within your redux store, at which point you can fire navigation actions using your redux dispatch function.

Keep in mind that when a navigator is given a navigation prop, it relinquishes control of its internal state. That means you are now responsible for persisting its state, handling any deep linking, integrating the back button, etc.

Navigation state is automatically passed down from one navigator to another when you nest them. Note that in order for a child navigator to receive the state from a parent navigator, it should be defined as a screen.

Applying this to the example above, you could instead define AppNavigator to contain a nested TabNavigator as follows:

const AppNavigator = StackNavigator({
  Home: { screen: MyTabNavigator },
});

In this case, once you connect AppNavigator to Redux as is done in AppWithNavigationState, MyTabNavigator will automatically have access to navigation state as a navigation prop.

Full example

There's a working example app with redux here if you want to try it out yourself.

Mocking tests

To make jest tests work with your react-navigation app, you need to change the jest preset in the package.json, see here:

"jest": {
  "preset": "react-native",
  "transformIgnorePatterns": [
    "node_modules/(?!(jest-)?react-native|react-navigation)"
  ]
}