Screen Tracking / Analytics
You might want to do some screen tracking in your apps. Since the entire navigation state is in redux, screen tracking is as simple as writing a redux middleware. Below is a simple middleware that uses routeName
as the screen name for tracking screens.
import SegmentIO from 'react-native-segment-io-analytics';
const navigationStateKey = 'navigation';
// gets the current screen from navigation state
function getCurrentScreen(getStateFn) {
const navigationState = getStateFn()[navigationStateKey];
// navigationState can be null when exnav is initializing
if (!navigationState) return null;
const { currentNavigatorUID, navigators } = navigationState;
if (!currentNavigatorUID) return null;
const { index, routes } = navigators[currentNavigatorUID];
const { routeName } = routes[index];
return routeName;
}
const screenTracking = ({ getState }) => next => action => {
if (!action.type.startsWith('EX_NAVIGATION')) return next(action);
const currentScreen = getCurrentScreen(getState);
const result = next(action);
const nextScreen = getCurrentScreen(getState);
if (nextScreen !== currentScreen) {
SegmentIO.screen(nextScreen);
}
return result;
}
export default screenTracking;
Android back button handling
React Native includes a global BackHandler
module. Rather than using this module
directly, include the AndroidBackButtonBehavior
component in routes where you'd
like to control the back button. AndroidBackButtonBehavior
accepts
isFocused
and onBackButtonPress
. If isFocused
is true, the onBackButtonPress
will fire when the user presses the back button. You need to make sure that onBackButtonPress
returns a promise that wraps the function you want to be called. Eg.
<AndroidBackButtonBehavior isFocused={someboolean}
onBackButtonPress={()=>Promise.resolve(fireMeWhenSomeBooleanIsTrue)}>
...
</AndroidBackButtonBehavior>