UIDatePicker show only Sunday's date only?

Question

How we can set UIDatePicker values to show only Sunday's date in swift iOS ?

Answer 1

finally, I myself found solution. In didSelectRow Method check if the selected day is sunday??? if yes then ok but if not then reload component to select date of nearest sunday.

func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {

    if component == 0 {
        pickerView.reloadComponent(1)
    }

    let titleLabel = pickerView.viewForRow(row, forComponent: component) as? UILabel
    titleLabel?.font = UIFont(name: BCGConstants.Fonts.Name.ProximaNovaBold, size: 27)!

    var dayValue = pickerView.selectedRowInComponent(1) + 1
    let monthValue = pickerView.selectedRowInComponent(0) + 1
    var yearValue = 0

    let unitFlags: NSCalendarUnit = [.Day, .Month, .Year, .Weekday]
    let currentDateComponents = NSCalendar.currentCalendar().components(unitFlags, fromDate: NSDate())

    if monthValue > currentDateComponents.month || (dayValue >= currentDateComponents.day && monthValue == currentDateComponents.month ) {
        yearValue = currentDateComponents.year
    } else {
        yearValue = currentDateComponents.year + 1
    }


    debugPrint("\(self.isGivenDaySunday(dayValue, selectedMonth: monthValue, selectedYear: yearValue)) day = \(dayValue) month = \(monthValue) )")

    let sundayCheck = self.isGivenDaySunday(pickerView.selectedRowInComponent(1) + 1, selectedMonth: pickerView.selectedRowInComponent(0) + 1, selectedYear: yearValue)

   if sundayCheck.isSunday {

        self.startDateTextField.text = sundayCheck.sundayDate?.fullStyleDateString
        self.newBootcamp?.startDate = sundayCheck.sundayDate!


    } else {


        //            titleLabel?.font = UIFont(name: BCGConstants.Fonts.Name.ProximaNovaBold, size: 27)!
        //            titleLabel?.textColor = UIColor.lightGrayColor()

        if dayValue > 15 {
            dayValue = pickerView.selectedRowInComponent(1) - (7 - sundayCheck.nextSundayAsWeekDay)

            pickerView.selectRow(dayValue, inComponent: 1, animated: true)
        } else {
            dayValue = pickerView.selectedRowInComponent(1) + sundayCheck.nextSundayAsWeekDay

            pickerView.selectRow(dayValue, inComponent: 1, animated: true)
        }


        var confirmSunday = self.isGivenDaySunday(dayValue + 1, selectedMonth: monthValue, selectedYear: yearValue)
      //  Added by mohsin : Reason bug : selecting previous day
        if confirmSunday.sundayDate?.isLessThanDate(NSDate()) == true {

             confirmSunday = self.isGivenDaySunday(dayValue, selectedMonth: monthValue, selectedYear: yearValue + 1)
            //TODO: Need to be verify again : If not working fine then you must try to change next commented statement and uncomment it
            // dayValue = pickerView.selectedRowInComponent(1) + sundayCheck.nextSundayAsWeekDay

            pickerView.selectRow(dayValue - 1, inComponent: 1, animated: true)

        }

        self.startDateTextField.text = confirmSunday.sundayDate?.fullStyleDateString
        self.newBootcamp?.startDate = confirmSunday.sundayDate!

        debugPrint(confirmSunday.sundayDate?.fullStyleDateString)


    }

}

Method which checks sunday is following one

func isGivenDaySunday(selectedDay: Int, selectedMonth: Int, selectedYear: Int) -> (isSunday: Bool, nextSundayAsWeekDay: Int, sundayDate: NSDate?) { let unitFlags: NSCalendarUnit = [.Day, .Month, .Year, .Weekday]

    let selectedDateComponents = NSDateComponents()

    selectedDateComponents.month = selectedMonth
    selectedDateComponents.day = selectedDay
    selectedDateComponents.year = selectedYear

    let selectedDate = NSCalendar(identifier: NSCalendarIdentifierGregorian)?.dateFromComponents(selectedDateComponents)

    let newSelectedDateComponent = NSCalendar.currentCalendar().components(unitFlags, fromDate: selectedDate!)

    if newSelectedDateComponent.weekday == 1 { // 1 means SUNDAY as per Gregorian
        return (true, 0, selectedDate)
    } else {
       return (false, 8 - newSelectedDateComponent.weekday, nil) 

    }

}