I have a datepicker and 2 buttons. And I want to set the datepicker value programmatically when I click the button. Like when I press the first button the datepicker value becomes today's date and 00:00:00: time and when I press the second button the datepicker value becomes today's date and 23:59:59 time.
How to do that?
Simple task, assuming that you already added two functions beging invoked on button pressing you need something like this:
-(IBAction)beginPressed:(id)sender
{
NSDate * now = [[NSDate alloc] init];
NSCalendar *cal = [NSCalendar currentCalendar];
NSDateComponents * comps = [cal components:NSYearCalendarUnit|NSMonthCalendarUnit|NSDayCalendarUnit fromDate:now];
[comps setHour:0];
[comps setMinute:0];
[comps setSecond:0];
NSDate * date = [cal dateFromComponents:comps];
[self.datePicker setDate:date animated:TRUE];
}
-(IBAction)endPressed:(id)sender
{
NSDate * now = [[NSDate alloc] init];
NSCalendar *cal = [NSCalendar currentCalendar];
NSDateComponents * comps = [cal components:NSYearCalendarUnit|NSMonthCalendarUnit|NSDayCalendarUnit fromDate:now];
[comps setHour:23];
[comps setMinute:59];
[comps setSecond:59];
NSDate * date = [cal dateFromComponents:comps];
[self.datePicker setDate:date animated:TRUE];
}
I think the part with setting the components wasn't clear to you, check the API of the above classes and you will find more.
Edit: I changed the calendar to the current default calendar and initialized the calendar with now.
NSDateFormatter *dateFormat;
dateFormat = [[NSDateFormatter alloc] init];
[dateFormat setDateFormat:#"h:mm a"];
NSDate *exampleDateFromString =[dateFormat dateFromString:#"8:48 AM"];
date-picker.minimumDate=exampleDateFromString;
[date-picker setDate:exampleDateFromString];
For those wondering how to do this in Swift:
let now = NSDate()
let cal = NSCalendar.currentCalendar()
let comp = cal.components([.Year, .Month, .Day], fromDate: now)
comp.hour = 0 // or whatever you need
comp.minute = 0
let date = cal.dateFromComponents(comp)!
picker.setDate(date, animated: true)
Related
What is the most efficient way to obtain an NSDate object that represents midnight of the current day?
New API in iOS 8
iOS 8 includes a new method on NSCalendar called startOfDayForDate, which is really easy to use:
let startOfToday = NSCalendar.currentCalendar().startOfDayForDate(NSDate())
Apple's description:
This API returns the first moment date of a given date.
Pass in [NSDate date], for example, if you want the start of "today".
If there were two midnights, it returns the first. If there was none, it returns the first moment that did exist.
Update, regarding time zones:
Since startOfDayForDate is a method on NSCalendar, it uses the NSCalendar's time zone. So if I wanted to see what time it was in New York, when today began in Los Angeles, I could do this:
let losAngelesCalendar = NSCalendar.currentCalendar().copy() as! NSCalendar
losAngelesCalendar.timeZone = NSTimeZone(name: "America/Los_Angeles")!
let dateTodayBeganInLosAngeles = losAngelesCalendar.startOfDayForDate(NSDate())
dateTodayBeganInLosAngeles.timeIntervalSince1970
let dateFormatter = NSDateFormatter()
dateFormatter.dateStyle = .MediumStyle
dateFormatter.timeStyle = .ShortStyle
dateFormatter.timeZone = NSTimeZone(name: "America/New_York")!
let timeInNewYorkWhenTodayBeganInLosAngeles = dateFormatter.stringFromDate(dateTodayBeganInLosAngeles)
print(timeInNewYorkWhenTodayBeganInLosAngeles) // prints "Jul 29, 2015, 3:00 AM"
Try this:
NSDate *const date = NSDate.date;
NSCalendar *const calendar = NSCalendar.currentCalendar;
NSCalendarUnit const preservedComponents = (NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay);
NSDateComponents *const components = [calendar components:preservedComponents fromDate:date];
NSDate *const normalizedDate = [calendar dateFromComponents:components];
NSCalendar *cal = [[[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar] autorelease];
[cal setTimeZone:[NSTimeZone systemTimeZone]];
NSDateComponents * comp = [cal components:( NSYearCalendarUnit| NSMonthCalendarUnit | NSDayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit) fromDate:[NSDate date]];
[comp setMinute:0];
[comp setHour:0];
[comp setSecond:0];
NSDate *startOfToday = [cal dateFromComponents:comp];
If you mean midnight as 23:59 then set component's hour as 23 and minutes as 59.
Swift:
let cal = NSCalendar.currentCalendar()
//tip:NSCalendarUnit can be omitted, but with the presence of it, you can take advantage of Xcode's auto-completion
var comps = cal.components(NSCalendarUnit.YearCalendarUnit | .MonthCalendarUnit | .DayCalendarUnit | .HourCalendarUnit | .MinuteCalendarUnit | .SecondCalendarUnit, fromDate: NSDate())
comps.hour = 0
comps.minute = 0
comps.second = 0
let midnightOfToday = cal.dateFromComponents(comps)!
Swift 2.2:
let cal = NSCalendar.currentCalendar()
let comps = cal.components([.Year, .Month, .Day, .Hour, .Minute, .Second], fromDate: NSDate())
comps.hour = 0
comps.minute = 0
comps.second = 0
let midnightOfToday = cal.dateFromComponents(comps)!
Objective-C:
NSCalendar *cal = [NSCalendar currentCalendar];
NSDateComponents *comps = [cal components:(NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay | NSCalendarUnitHour | NSCalendarUnitMinute) fromDate:[NSDate date]];
[comps setHour:0];
[comps setMinute:0];
[comps setSecond:0];
NSDate *midnightOfToday = [cal dateFromComponents:comps];
You could use the following method to get the midnight value for an NSDate.
- (NSDate *)dateAtBeginningOfDayForDate:(NSDate *)inputDate
{
// Use the user's current calendar and time zone
NSCalendar *calendar = [NSCalendar currentCalendar];
NSTimeZone *timeZone = [NSTimeZone systemTimeZone];
[calendar setTimeZone:timeZone];
// Selectively convert the date components (year, month, day) of the input date
NSDateComponents *dateComps = [calendar components:NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit fromDate:inputDate];
// Set the time components manually
[dateComps setHour:0];
[dateComps setMinute:0];
[dateComps setSecond:0];
// Convert back
NSDate *beginningOfDay = [calendar dateFromComponents:dateComps];
return beginningOfDay;
}
Thkis is taken from here website.
From iOS8, you can use startDayForDate.
So, in order to get the start of today (Objective -C):
NSDate * midnight;
midnight = [[NSCalendar currentCalendar] startOfDayForDate: [NSDate date]];
try this:
NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDate *now = [NSDate date];
NSDateComponents *components = [gregorian components:NSDayCalendarUnit | NSMonthCalendarUnit | NSYearCalendarUnit fromDate:now];
NSDateFormatter* df = [[NSDateFormatter alloc]init];
[df setDateFormat:#"MM/dd/yyyy HH:mm:ss.SSS"];
NSLog(#"%#",[df stringFromDate:[gregorian dateFromComponents:components]]);
NSDate *now = [NSDate date];
NSDate *beginningOfToday = nil;
[[NSCalendar currentCalendar] rangeOfUnit:NSDayCalendarUnit startDate:&beginningOfToday interval:NULL forDate:now];
You could use NSCalendar's dateBySettingHour:minute:second:ofDate:options:
So it would be as easy as doing:
NSCalendar *calendar = [NSCalendar currentCalendar];
calendar.timeZone = [NSTimeZone timeZoneWithName:#"UTC"];
NSDate *midnight = [calendar dateBySettingHour:0 minute:0 second:0 ofDate:[NSDate date] options:0];
let calendar = NSCalendar.currentCalendar()
let unitFlags: NSCalendarUnit = [.Year, .Month, .Day, .Minute, .Second]
let components = calendar.components(unitFlags , fromDate: NSDate())
components.hour = 0
components.minute = 0
components.second = 0
//Gives Midnight time of today
let midnightOfToday = calendar.dateFromComponents(components)!
I am getting date value date: 2013-06-07 18:30:00 +0000. I am trying to subtract 30 minutes from this, but it not giving proper time.
I've tried this
NSTimeInterval secondsPerHour = 60*30;
NSDate *newDate = [date dateByAddingTimeInterval:-secondsPerHour];
Reason : The negative of a unsigned int is a positive number. This should work:
NSDate *newDate = [date dateByAddingTimeInterval:-(NSTimeInterval)((u_int32_t)30*60)];
EDIT : Alternative use NSDateComponents.
NSDateComponents *dateComponents = [[NSDateComponents alloc] init];
[dateComponents setMinute:-30];
NSDate *halfHourAgo = [[NSCalendar currentCalendar] dateByAddingComponents:dateComponents toDate:yourDateHere options:0];
NSLog(#"\ncurrentDate: %# \n halfHourAgo: %#", yourDateHere, halfHourAgo);
in Swift 5
let minus30Min = Date().addingTimeInterval(-30 * 60)
you can use:
NSDate *minusOneHr = [[NSDate date] dateByAddingTimeInterval:-30*60];
You could try NSDateComponents, something like that:
NSDate* yourDate = [NSDate dateWithTimeIntervalSinceNow:0]; // your date, to substract 30 mins
NSDateComponents *dc = [[NSCalendar currentCalendar] components:(NSYearCalendarUnit| NSMonthCalendarUnit | NSDayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit) fromDate:yourDate];
[dc setMinute:[dc minute] - 30];
NSDate* date = [[NSCalendar currentCalendar] dateFromComponents:dc]; // 30 mins before now
Or that:
NSDate* yourDate = [NSDate dateWithTimeIntervalSinceNow:0]; // your date, to substract 30 mins
NSDateComponents *components = [[NSDateComponents alloc] init];
[components setMinute:-30];
NSDate* date = [[NSCalendar currentCalendar] dateByAddingComponents:components toDate:yourDate options:0]; // 30 mins before now
Copy paste this code in viewDidLoad and check the results first.
NSDate *today = [[NSDate alloc] init];
NSLog(#"Today %#", today);
NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDateComponents *offsetComponents = [[NSDateComponents alloc] init];
[offsetComponents setMinute:-30]; // If you want to change Month,Year,Day,Hour etc. Just change the "setMinute" to setMonth,setYear,setDay,setHour
NSDate *dateComp = [gregorian dateByAddingComponents:offsetComponents toDate:today options:0];
NSLog(#"Desired Day %#", dateComp);
let dateMinusThirtyMinutes = Date().subtract(30.minutes)
I am new to iPhone developer,
I made a one custom date in that custom date i want to add 1 month or 3 month or 6 month according to frequency.
i want to add month till newDate is less then today's date.
here is my code snippet,
while ([today compare:temp] == NSOrderedDescending)
{
NSLog(#"inside----- today=%#,temp=%#",today,temp);
//add to dates
NSDateComponents *newComponents= [[NSDateComponents alloc] init];
if([FrequencySelText isEqualToString:#"Monthly"]){
[newComponents setMonth:1];
}
if([FrequencySelText isEqualToString:#"Quarterly"]){
[newComponents setMonth:3];
}
if([FrequencySelText isEqualToString:#"Half - Yearly"]){
[newComponents setMonth:6];
}
if([FrequencySelText isEqualToString:#"Yearly"]){
[newComponents setMonth:12];
}
// get a new date by adding components
NSDate* temp= [[NSCalendar currentCalendar] dateByAddingComponents:newComponents toDate:temp options:0];
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:#"dd/MM/yyyy"];
NSString *newDate = [formatter stringFromDate:temp];
NSLog(#"new date=%#",newDate);
}
My Log shows: inside----- today=2012-07-11 14:41:27 +0000,temp=2012-04-12 03:00:00 +0000
I am getting Exc_bad_access at this line, NSDate* temp= [[NSCalendar currentCalendar] dateByAddingComponents:newComponents toDate:temp options:0];
Any help will bw appreciated.
Providing value to temp again then no need provide NSDate object type again. Here u already have NSDate *temp then why r u using same name again for NSDate object
temp= [[NSCalendar currentCalendar] dateByAddingComponents:newComponents toDate:temp options:0]
Maybe try this one:
NSDateComponents *dateComponents = [[[NSDateComponents alloc] init] autorelease];
NSCalendar *gregorian = [[[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar] autorelease];
[dateComponents setMonth:1]; // Sample Add
NSDate *tempDate = [gregorian dateByAddingComponents:dateComponents toDate: temp options:0];
NSString *strTempDate = [dateFormat stringFromDate:tempDate];
// New Date on strTempDate
I need to get an NSDate object for 00:00(beginning of the day) from [NSDate date], let's say if currently it is 11:30am(returned by [NSDate date]), on 01/06/2012, now I need to have an NSDate for 00:00am on 01/06/2012.
I haven't tried this, but what is in my mind is:
NSDate *now = [NSDate date];
NSCalendar *calendar = [NSCalendar currentCalendar];
NSDateComponents *components = [calendar components:(NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit) fromDate:now];
[components setHour:0];
[components setMinute:0];
[components setSecond:0];
NSDate *morningStart = [calendar dateFromComponents:components];
So I first get current date(say it is 01/06/2012), and construct a NSDateComponent for the date, then I set hour/minute/second to 0 and the year/month/day should not be changed(ie. 01/06/2012) then I create an NSDate for this component setting and can I get a date of 00:00:00 01/06/2012?
What you doing is correct, but when you NSLog morningStart the date will be displayed in GMT time zone
If you wanna make sure that the date is correct, convert it to NSString
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:#"yyyy-MMM-dd HH:mm:ss"];
NSString *strFromDate = [formatter stringFromDate:morningStart]; // this will return 2012-Jun-21 00:00:00
Converting NSDate to NSString can be helpful but if you need to keep a NSDate object for further processing, here is your solution to have your real morningStart NSDate object set at 00:00:00 time, with care of the timezone as well... As you will see you were not so far from the solution :
NSDate *now = [NSDate date];
NSCalendar *calendar = [NSCalendar currentCalendar];
NSDateComponents *components = [calendar components:(NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit) fromDate:now];
NSTimeZone* destinationTimeZone = [NSTimeZone systemTimeZone];
int timeZoneOffset = [destinationTimeZone secondsFromGMTForDate:now] / 3600;
[components setHour:timeZoneOffset];
[components setMinute:0];
[components setSecond:0];
NSDate *morningStart = [calendar dateFromComponents:components];
It's very easy to do this in iOS8 using startOfDayForDate:
let date = NSDate()
let calendar = NSCalendar.currentCalendar(calendarIdentifier: NSGregorianCalendar)
let dateAtStartOfDay = calendar.startOfDayForDate(date)
OR you may do it in the traditional way in Swift as follows:
let date = NSDate()
let calendar = NSCalendar.currentCalendar(calendarIdentifier: NSGregorianCalendar)
// Use a mask to extract the required components from today's date
let components = calendar.components(.CalendarUnitYear | .CalendarUnitMonth | .CalendarUnitDay, fromDate: date)
let dateAtStartOfDay = calendar.dateFromComponents(components)!
print(dateAtStartOfDay)
(Note: NSDates are stored relative to GMT. So print will display the relative local time. A clear understanding of TimeZone's is essential to using NSDates properly.)
Does anyone know if there is a way to set the first day of the week on a NSCalendar, or is there a calendar that already has Monday as the first day of the week, instead of Sunday.
I'm currently working on an app that is based around a week's worth of work, and it needs to start on Monday, not Sunday. I can most likely do some work to work around this, but there will be a lot of corner cases. I'd prefer the platform do it for me.
Thanks in advance
Here's some the code that I'm using. it's saturday now, so what I would hope is that weekday would be 6, instead of 7. that would mean that Sunday would be 7 instead of rolling over to 0
NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
[gregorian setFirstWeekday:0];
unsigned unitFlags = NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit | NSWeekCalendarUnit | NSWeekdayCalendarUnit;
NSDateComponents *todaysDate = [gregorian components:unitFlags fromDate:[NSDate date]];
int dayOfWeek = todaysDate.weekday;
Edit: This does not check the edge case where the beginning of the week starts in the prior month. Some updated code to cover this: https://stackoverflow.com/a/14688780/308315
In case anyone is still paying attention to this, you need to use
ordinalityOfUnit:inUnit:forDate:
and set firstWeekday to 2. (1 == Sunday and 7 == Saturday)
Here's the code:
NSCalendar *gregorian = [[[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar] autorelease];
[gregorian setFirstWeekday:2]; // Sunday == 1, Saturday == 7
NSUInteger adjustedWeekdayOrdinal = [gregorian ordinalityOfUnit:NSWeekdayCalendarUnit inUnit:NSWeekCalendarUnit forDate:[NSDate date]];
NSLog(#"Adjusted weekday ordinal: %d", adjustedWeekdayOrdinal);
Remember, the ordinals for weekdays start at 1 for the first day of the week, not zero.
Documentation link.
This code constructs a date that is set to Monday of the current week:
NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDate *today = [NSDate date];
NSDate *beginningOfWeek = nil;
BOOL ok = [gregorian rangeOfUnit:NSWeekCalendarUnit startDate:&beginningOfWeek
interval:NULL forDate: today];
setFirstWeekday: on the NSCalendar object.
Sets the index of the first weekday for the receiver.
- (void)setFirstWeekday:(NSUInteger)weekday
Should do the trick.
In my opinion this settings should be dynamic according to the user locale.
Therefore one should use:
NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
[gregorian setLocale:[NSLocale currentLocale]];
This will cause the calendar to set the first week day according to the user locale automatically. Unless you are developing your app for a specific purpose/user locale (or prefer to allow the user to choose this day).
I've done it like this.
NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDate *today = [NSDate date];
NSDateComponents *compForWeekday = [gregorian components:(NSWeekdayCalendarUnit) fromDate:today];
NSInteger weekDayAsNumber = [compForWeekday weekday]; // The week day as number but with sunday starting as 1
weekDayAsNumber = ((weekDayAsNumber + 5) % 7) + 1; // Transforming so that monday = 1 and sunday = 7
I had trouble with a lot of the answers here. . maybe it was just me. .
Here's an answer that works for me:
- (NSDate*)firstDayOfWeek
{
NSCalendar* cal = [[NSCalendar currentCalendar] copy];
[cal setFirstWeekday:2]; //Override locale to make week start on Monday
NSDate* startOfTheWeek;
NSTimeInterval interval;
[cal rangeOfUnit:NSWeekCalendarUnit startDate:&startOfTheWeek interval:&interval forDate:self];
return startOfTheWeek;
}
- (NSDate*)lastDayOfWeek
{
NSCalendar* cal = [[NSCalendar currentCalendar] copy];
[cal setFirstWeekday:2]; //Override locale to make week start on Monday
NSDate* startOfTheWeek;
NSTimeInterval interval;
[cal rangeOfUnit:NSWeekCalendarUnit startDate:&startOfTheWeek interval:&interval forDate:self];
return [startOfTheWeek dateByAddingTimeInterval:interval - 1];
}
Update:
As pointed out (elsewhere) by #vikingosegundo, in general its best to let the local determine which day is the start of the week, however in this case the OP was asking for the start of the week to occur on Monday, hence we copy the system calendar, and override the firstWeekDay.
The problem with Kris' answer is the edge case where the beginning of the week starts in the prior month. Here's some easier code and it also checks the edge case:
// Finds the date for the first day of the week
- (NSDate *)getFirstDayOfTheWeekFromDate:(NSDate *)givenDate
{
NSCalendar *calendar = [NSCalendar currentCalendar];
// Edge case where beginning of week starts in the prior month
NSDateComponents *edgeCase = [[NSDateComponents alloc] init];
[edgeCase setMonth:2];
[edgeCase setDay:1];
[edgeCase setYear:2013];
NSDate *edgeCaseDate = [calendar dateFromComponents:edgeCase];
NSDateComponents *components = [calendar components:NSYearCalendarUnit|NSMonthCalendarUnit|NSWeekCalendarUnit|NSWeekdayCalendarUnit fromDate:edgeCaseDate];
[components setWeekday:1]; // 1 == Sunday, 7 == Saturday
[components setWeek:[components week]];
NSLog(#"Edge case date is %# and beginning of that week is %#", edgeCaseDate , [calendar dateFromComponents:components]);
// Find Sunday for the given date
components = [calendar components:NSYearCalendarUnit|NSMonthCalendarUnit|NSWeekCalendarUnit|NSWeekdayCalendarUnit fromDate:givenDate];
[components setWeekday:1]; // 1 == Sunday, 7 == Saturday
[components setWeek:[components week]];
NSLog(#"Original date is %# and beginning of week is %#", givenDate , [calendar dateFromComponents:components]);
return [calendar dateFromComponents:components];
}
I see misunderstanding in the other messages. The first weekday, whichever it is, has number 1 not 0. By default Sunday=1 as in the "Introduction to Date and Time Programming Guide for Cocoa: Calendrical Calculations":
"The weekday value for Sunday in the Gregorian calendar is 1"
For the Monday as a first workday the only remedy I have is brute force condition to fix the calculation
NSCalendar *cal=[[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDateComponents *comps = [cal components:NSWeekdayCalendarUnit fromDate:[NSDate date]];
// set to 7 if it's Sunday otherwise decrease weekday number
NSInteger weekday=[comps weekday]==1?7:[comps weekday]-1;
Below also covers the edge case,
- (NSDate *)getFirstDayOfTheWeekFromDate:(NSDate *)givenDate
{
NSCalendar *calendar = [NSCalendar currentCalendar];
NSDateComponents *components = [calendar components:NSYearCalendarUnit|NSMonthCalendarUnit|NSWeekCalendarUnit|NSWeekdayCalendarUnit fromDate:givenDate];
[components setWeekday:2]; // 1 == Sunday, 7 == Saturday
if([[calendar dateFromComponents:components] compare: curDate] == NSOrderedDescending) // if start is later in time than end
{
[components setWeek:[components week]-1];
}
return [calendar dateFromComponents:components];
}
You can just change .firstWeekday of the calendar.
NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSCalendarIdentifierGregorian];
calendar.firstWeekday = 2;
Then use rangeOfUnit:startDate:interval:forDate: to get the first day
NSDate *startOfWeek;
[calendar rangeOfUnit:NSCalendarUnitWeekOfYear startDate:&startOfWeek interval:nil forDate:[NSdate date]];
Try this:
NSCalendar *yourCal = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar]
[yourCal setFirstWeekday:0];
Iv found out the way to display any weekday name using nscalender..using the following code..
Just open your console from xcode menu bar to see the results.Copy Paste the following code in your viewDidLoad method to get the first day of the week
NSDate *today = [NSDate date];
NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
[dateFormat setDateFormat:#"MM/dd/yyyy :EEEE"];
NSString *dateString = [dateFormat stringFromDate:today];
NSLog(#"date: %#", dateString);
[dateFormat release];
NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDateComponents *components = [gregorian components:NSWeekdayCalendarUnit | NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit fromDate:today];
[components setDay:([components day]-([components weekday]-1))];
NSDate *beginningOfWeek = [gregorian dateFromComponents:components];
NSDateFormatter *dateFormat_first = [[NSDateFormatter alloc] init];
[dateFormat_first setDateFormat:#"MM/dd/yyyy :EEEE"];
NSString *dateString_first = [dateFormat_first stringFromDate:beginningOfWeek];
NSLog(#"First_date: %#", dateString_first);
The Output will be:
date: 02/11/2010 :Thursday
First_date: 02/07/2010 :Sunday
since i had run this program on 2/11/2010 u will get the desired output depending on the current date.
Similarly if u want to get the first working day of the week i.e Monday's date then just modify the code a bit:
CHANGE :[components setDay:([components day]-([components weekday]-1))];
TO
[components setDay:([components day]-([components weekday]-2))];
to get Mondays date for that week..
Similarly u can try to find the date of any of seven workdays by changing the integer -1,-2 and so on...
Hope u r question is answered..
Thanks,
Bonson Dias
The ISO 8601 calendar appears to have it's first weekday set to monday by default.
Using the Calendar nextWeekend (iOS 10 or later) and ordinality (thanks #kris-markel). I've gotten Monday as first of the week for the en_US calendar.
Here is an example of it with fallback to firstWeekday:
extension Calendar {
var firstWorkWeekday: Int {
guard #available(iOS 10.0, *) else{
return self.firstWeekday
}
guard let endOfWeekend = self.nextWeekend(startingAfter: Date())?.end else {
return self.firstWeekday
}
return self.ordinality(of: .weekday, in: .weekOfYear, for: endOfWeekend) ?? self.firstWeekday
}
}
The Swift solution (note, use .yearForWeekOfYear, not .year):
let now = Date()
let cal = Calendar.current
var weekComponents = cal.dateComponents([.yearForWeekOfYear, .weekOfYear,
.weekday], from: now)
//weekComponents.weekday = 1 // if your week starts on Sunday
weekComponents.weekday = 2 // if your week starts on Monday
cal.date(from: weekComponents) // returns date with first day of the week
… is there a calendar that already has Monday as the first day of the week, instead of Sunday.
Someday, there will be.
My simple way of doing this is to get Monday = 0, Sunday = 6:
NSDateComponents *dateComponents = [[NSCalendar currentCalendar] components:NSWeekdayCalendarUnit fromDate:[NSDate date]];
NSInteger dayNumStartingFromMonday = ([dateComponents weekday] - 2 + 7) % 7; //normal: Sunday is 1, Monday is 2