swift Ekevents to 2 dimensional array sorted by Date - swift

Question

I have an array with events which are sorted by date. I want a separate section for each day [monday], [tuesday], ....
How do I create a 2-dimensional array that looks like this?
And how do i get each event in the appropriate section?
[
[monday]
[tuesday]
[wednesday]
. .and so on ]
func getEvents(){
let calendars = eventStore.calendars(for: .event)
for calendar in calendars {
// if calendar.title == "Arbeit" {
let anfang = NSDate()
let ende = Calendar.current.date(byAdding: .day, value: 6, to: anfang as Date)!
let predicate = eventStore.predicateForEvents(withStart: anfang as Date, end: ende as Date, calendars: [calendar])
let events = eventStore.events(matching: predicate)
var found:Bool = false
for event in events {
if (allEvents.count == 0)
{
allEvents.append(event)
}
if (allEvents.count > 0)
{
found = false
if ( event.title == allEvents[allEvents.count-1].title && event.startDate == allEvents[allEvents.count-1].startDate)
{
found = true
}
}
if(!found)
{
allEvents.append(event)
}
}

Answer 1

The following solution first groups the events based start date by weekday in a dictionary and then transforms the dictionary to a 2D array sorted with todays day first
First set up a Calendar and DateFormatter to use
let locale = Locale(identifier: "en_US_POSIX")
var calendar = Calendar.current
calendar.locale = locale
let formatter = DateFormatter()
formatter.locale = locale
formatter.dateFormat = "EEEE"
Group the events
let byWeekday = Dictionary(grouping: events, by: { formatter.string(from: $0.startDate) })
Get the weekdays in the right order
let weekdays = calendar.weekdaySymbols
let todayIndex = weekdays.firstIndex(of: formatter.string(from: Date())) ?? calendar.weekdaySymbols.startIndex
let sortedWeekdays = weekdays[todayIndex..<weekdays.endIndex] + weekdays[weekdays.startIndex..<todayIndex]
and then create and fill the array
var eventsByDay = [[EKEvent]]()
for day in sortedWeekdays {
eventsByDay.append(byWeekday[day] ?? [])
}