Display annotation views on the Map screen

The Map screen at present displays a map region centered on your device location. Now that the map region has been set, you can determine which JournalEntry instances are in this region based on their coordinate property. Remember that the JournalEntry class conforms to MKAnnotation. As the view controller for the map view, the MapViewController class is responsible for providing an MKAnnotationView instance for any MKAnnotation instance within this region.

You will now modify the MapViewController class to get an array of JournalEntry instances from the createSampleJournalEntryData() method and add it to the map view. Follow these steps:

1. In the Project navigator, click on the JournalEntry file. In the createSampleJournalEntryData() method, modify the statement that creates the journalEntry2 instance, as shown:

   guard let journalEntry2 = JournalEntry(rating: 0, title: "Bad", body: "Today is a bad day...