How to make 30 minute time intervals in swift 2.3 - ios

Question

startTime = 10:00 AM
endTime = 01:00 PM
Now i want to split the time in the interval of 30mins like
10:00 AM 10:30 AM 11:00 AM 11:30 AM .......... till 01:00 PM.
I tried like
let startDate : NSDate! = NSDate()
let time1 : NSDate = startDate.dateByAddingTimeInterval((60*60)/2)
let time2 : NSDate = time1.dateByAddingTimeInterval((60*60)/2)
let time3 : NSDate = time2.dateByAddingTimeInterval((60*60)/2)
let time4 : NSDate = time3.dateByAddingTimeInterval((60*60)/2)
func makeTimeInterval(startTime:String ,endTime:String) -> String
{
let timeFormat = DateFormatter()
timeFormat.dateFormat = "hh:mm a"
var fromTime:NSDate = (timeFormat.date(from:startTime) as NSDate?)!
let toTime:NSDate = (timeFormat.date(from:endTime) as NSDate?)!
var dateByAddingThirtyMinute : NSDate!
let timeinterval : TimeInterval = toTime.timeIntervalSince(fromTime as Date)
let numberOfIntervals : Double = timeinterval / 3600;
var formattedDateString : String!
for _ in stride(from: 0, to: Int(numberOfIntervals * 2), by: 1)
{
dateByAddingThirtyMinute = fromTime.addingTimeInterval(1800)
fromTime = dateByAddingThirtyMinute
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "hh:mm a"
formattedDateString = dateFormatter.string(from: dateByAddingThirtyMinute! as Date) as String?
print("Time after 30 min = \(formattedDateString)")
}
return formattedDateString
}
Tried those things and i got like 10:10,10:40..etc
how to make 30 min round of interval like 10:00,10:30...etc
Thanks in advance

Answer 1

Use the below function if user enters anytime less than 30 than it will start with very next 30 min e.g 10:20, start from 10:30. And if user give time greater than 30 then very time will be 00 e.g 10:45, start from 11:00.
func makeTimeInterval(startTime:String ,endTime:String) -> String
{
var arr = startTime.components(separatedBy: " ")[0].components(separatedBy: ":")
let str = arr[1] as String
if (Int(str)! > 0 && Int(str)! < 30){
arr[1] = "00"
}
else if(Int(str)! > 30){
arr[1] = "30"
}
let startT:String = "\(arr.joined(separator: ":")) \(startTime.components(separatedBy: " ")[1])"
let timeFormat = DateFormatter()
timeFormat.dateFormat = "hh:mm a"
var fromTime:NSDate = (timeFormat.date(from:startT) as NSDate?)!
let toTime:NSDate = (timeFormat.date(from:endTime) as NSDate?)!
var dateByAddingThirtyMinute : NSDate!
let timeinterval : TimeInterval = toTime.timeIntervalSince(fromTime as Date)
let numberOfIntervals : Double = timeinterval / 3600;
var formattedDateString : String!
for _ in stride(from: 0, to: Int(numberOfIntervals * 2), by: 1)
{
dateByAddingThirtyMinute = fromTime.addingTimeInterval(1800)
fromTime = dateByAddingThirtyMinute
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "hh:mm a"
formattedDateString = dateFormatter.string(from: dateByAddingThirtyMinute! as Date) as String?
print("Time after 30 min = \(formattedDateString)")
}
return formattedDateString
}

Answer 2

You can user Calendar Components to set minutes 00 and then calculate intervals:
func getIntervals(start: String, end: String)->[Date]{
let formatter = DateFormatter()
formatter.dateFormat = "hh:mm a"
var fromDate = formatter.date(from: start)!
let calendar = Calendar(identifier: .gregorian)
let component = calendar.dateComponents([.hour, .minute], from: fromDate)
fromDate = calendar.date(bySettingHour: component.hour!, minute: 0, second: 0, of: fromDate)!
let thirtyMin: TimeInterval = 1800
let endDate = formatter.date(from: end)!
var intervals = Int(endDate.timeIntervalSince(fromDate)/thirtyMin)
intervals = intervals < 0 ? 0 : intervals
var dates = [Date]()
for x in 0...intervals{
let date = fromDate.addingTimeInterval(TimeInterval(x)*thirtyMin)
dates.append(date)
}
return dates
}
let timeIntervals = getIntervals(start: "10:10 am", end: "1:40 pm")

Answer 3

You can use NSDateComponents class. This class allow to get some date units. You can get minutes and hours values from the date and round the minutes to nearest "good" value (sometimes you should be change hours also).
After that you can get new date with new values of hours and minutes.
Don't forget about a time zone.
NSDate* date = [NSDate date]; //start date
NSCalendar* calendar = [NSCalendar calendarWithIdentifier:NSCalendarIdentifierGregorian];
NSDateComponents* components = [calendar components:(NSCalendarUnitMinute | NSCalendarUnitHour) fromDate:date];
NSInteger minutes = [components minute];
NSInteger hours = [components hour];
NSInteger nearestGoodMinutes = [self _nearestGoodMinutesForMinutes:minutes];
BOOL shouldIncHours = [self _shouldINcHoursForMinutes:minutes];
if (shouldIncHours)
{
hours++;
}
NSDate* dateWithGoodHours = [calendar dateBySettingUnit:NSCalendarUnitHour value:hours ofDate:date options:kNilOptions];
NSDate* goodDate = [calendar dateBySettingUnit:NSCalendarUnitMinute value:nearestGoodMinutes ofDate:dateWithGoodHours options:kNilOptions];
Some explanation. NSDate does not contain any date components. Date components depend on current callendar. Also values of the components depent on current time zone. If you create NSCalendar with identifier, you will get calendar in current time zone. The time zone should be same with time zone that you use for displaying of the date to the user.
P.S.
You can do it only for the start date.

Answer 4

func format(minute: Int) {
let h = minute / 60
let m = minute % 60
timeLabel.text = "\(h.padZero()):\(m.padZero())"
}
private extension Int {
func padZero() -> String {
return String(format: "%02d", self)
}
}
Refered to this post https://github.com/onmyway133/blog/issues/340