leverdeterre/CalendarIOS7 — pull request #10 by bhirt-bpl (2014-07-29 23:33:47+00:00)
Title: performance fix for slow laggy scrolling.

NSDateFormatter has a big overhead for instantiating. If you run in the profiler, you will see that it's using a huge amount of time.

If you make sectionFormater a property of CALAgendaViewController, initialize it in viewDidLoad and reference it from -updateEventGroupByDays and -eventsAtIndexPath: you will see smooth scrolling, even on 4S iPhone.