Let's recap what happened when the user tapped on one feed on the FeedsList screen:
_handleFeedPress(feed) {
selectFeed(feed);
this.props.navigation.navigate('FeedDetail', { feedUrl: feed.url });
}The navigate method was called on the navigation property to open the FeedDetail screen. As a parameter, the _handleFeedPress function passed feedUrl, so it can retrieve the feed data and display it to the user. This is a necessary step since the data we have in our store for the selected feed can be obsolete. So, it's better to re-fetch that data before showing it to the user so we are sure it's 100% updated. We could also do a more complex check instead of retrieving the whole feed every time the user selects a feed, but we will stay with the given approach in order to keep simplicity in this app.
Let's start by retrieving the updated list of entries in the componentWillMount method:
/*** src/screens/FeedDetail.js ***/
import React from 'react';
import { observer...