星期一星期开始时，日标签不正确

Question

星期一星期开始时的日标签不正确。使用具有挪威语区域设置的应用程序，从星期一开始检测星期并正确绘制图表，但标签仍然从星期日开始。因此，本周被确定为“25.-31。mai”被标记为“søn.man.ti。...”（Sun Mon Tue ...），而不是“man.ti。ons .......”（星期一星期三...）。如何解决这个问题？

import UIKit

class STPYDateHelper: NSObject {

/**
Gets the day abbreviations for the week

:returns: The array of abbreviations
*/
class func dayAbbreviations() -> [String] {
    let calendar = NSCalendar.currentCalendar()
    calendar.timeZone = NSTimeZone.systemTimeZone()
    var comps = NSDateComponents()
    comps.day = 21
    comps.month = 12
    comps.year = 2014
    var date = calendar.dateFromComponents(comps)
    var strings = [String]()
    for var day = 0; day < 7; day++ {
        strings.append(STPYFormatter.sharedInstance.string(date!, format: "eee"))
        date = date?.nextDay()
    }
    return strings
  }
  }

  extension NSDate {

/**
Gets the next days date

:returns: The date
*/
func nextDay() -> NSDate {
    return dateByAddingTimeInterval(86400)
}

/**
Gets the last date of the previous day

:returns: The date
*/
func endOfPreviousDay() -> NSDate {
    return dateByAddingTimeInterval(-1)
}

/**
Gets the date for the beginning of the day

:returns: The date
*/
func beginningOfDay() -> NSDate {
    let calendar = NSCalendar.currentCalendar()
    calendar.timeZone = NSTimeZone.systemTimeZone()
    var dateComps = calendar.components(.CalendarUnitYear | .CalendarUnitMonth | .CalendarUnitDay, fromDate: self)
    dateComps.hour = 0
    dateComps.minute = 0
    dateComps.second = 0
    return calendar.dateFromComponents(dateComps)!
}

/**
Gets the date for the beginning of the week

:returns: The date
*/
func beginningOfWeek() -> NSDate {
    let calendar = NSCalendar.currentCalendar()
    calendar.timeZone = NSTimeZone.systemTimeZone()
    var date : NSDate?
    var interval : NSTimeInterval = 0
    calendar.rangeOfUnit(.CalendarUnitWeekOfYear, startDate: &date, interval: &interval, forDate: self)
    if let date = date {
        return date.beginningOfDay()
    }
    return NSDate()
}

/**
Gets the key for the beginning of the week

:returns: The key
*/
func beginningOfWeekKey() -> String {
    return beginningOfWeek().key()
}

/**
Gets a Steppy date key for the date

:returns: The key
*/
func key() -> String {
    return STPYFormatter.sharedInstance.string(self, format: "yyyy-MM-dd")
}

/**
Creates new NSDate instance from the Steppy date key

:param: key The Steppy date key
*/
convenience init(key : String) {
    self.init(timeInterval:0, sinceDate:STPYFormatter.sharedInstance.date(key, format: "yyyy-MM-dd"))
}
}