How to get date for every year of july month using NSDate .I am getting the data from the web service which I called. And now I am showing the full data in the graph which is very huge. The data which we are having is from 1998 to till now. so I want to show the data only every year of july. For this I need the help. Can anyone help me?
Well, NSDate is a specific date and time and not just month and year. If you're fine with something like every July 1 at 12 AM (or whatever time/day) then you can use NSDateComponents to set the components of the date.
NSDateComponents *comps = [[NSDateComponents alloc] init];
[comps setMonth:5];
[comps setYear:2004];
NSCalendar *gregorian = [[NSCalendar alloc]
initWithCalendarIdentifier:NSGregorianCalendar];
NSDate *date = [gregorian dateFromComponents:comps];
[comps release];
[gregorian release];
This is straight from the Apple documentation. If you want to get the next year, then you can use dateByAddingTimeInterval: on your NSDate to return a new date (or you can use the original NSDateComponents and setYear: in a loop).
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Is it possible to code a custom date picker for iOS in objective C to display only the last 30 days from today in this format: Day, Month Day, Year
I am trying to build a view that will display a list of item (fetched from API) based on the date selection but I only want the user to select from the last 30 days only. The entire date should be scrollable, not individual date or month.
Yes, overlapping the month.
For example:
Fri, May 19, 2017 ... scroll all the way back to... Wed, Apr 19, 2017
Thanks.
I think you want something like this.
NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSCalendarIdentifierGregorian];
NSDate *currentDate = [NSDate date];
NSDateComponents *comps = [[NSDateComponents alloc] init];
[comps setMonth: -1];
// or
//[comps setDay: -30];
NSDate *minDate = [calendar dateByAddingComponents:comps toDate:currentDate options:0];
[datePicker setMaximumDate:currentDate];
[datePicker setMinimumDate:minDate];
is there a way to get the first date of the current quarter of the year? I already know how to get the current Day of the week, month and year... i use this code:
NSCalendar* calendar = [NSCalendar currentCalendar];
NSDateComponents* comps = [calendar components:
NSCalendarUnitYearForWeekOfYear |
NSCalendarUnitYear|
NSCalendarUnitMonth|
NSCalendarUnitWeekOfMonth|
NSCalendarUnitWeekday
fromDate:[NSDate date]];
[comps setWeekday:2]; // 2: monday
NSDate * firstDayOfTheWeek = [calendar dateFromComponents:comps];
[comps setWeekday:1]; // 1: Sunday
NSDate *lastDayOfTheWeek = [calendar dateFromComponents:comps];
[comps setDay:1];
NSDate * firstDayOfTheMonth = [calendar dateFromComponents:comps];
Humm... It seems that using:
[comps setMonth:1];
is a buyable option provided, I determine the current month to plot the quarter (and encapsulate it into a switch statement), guess this might be easier but, what about other countries that have different way of measuring the "Quarter". for my current requirement, this will have to do but if someone can give me a better way of getting the current date of the current quarter.
I need to filter search results based on values that were added yesterday. I have seen plenty on finding yesterday using:
NSCalendar *cal = [NSCalendar currentCalendar];
NSDateComponents *components = [cal components:( NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit ) fromDate:[[NSDate alloc] init]];
[components setHour:-24];
[components setMinute:0];
[components setSecond:0];
NSDate *yesterday = [cal dateByAddingComponents:components toDate:[NSDate date] options:0];
predicate = [NSPredicate predicateWithFormat:#"created_at >= %#", yesterday];
But this finds 24 hours since this exact moment in time. I need to filter yesterday as 12:01am-12:00pm. So the actual 24 hour period that was yesterday.
I'm guessing that I need to do something along the lines of:
1. Take the current date
2. Find the time from the current date to 12:01am of the same day
3. Then subtract 24 hours from that date
I feel confident I can do #3 (and #1 of course), but I'm not sure how to go about #2. I maybe over thinking it but I can't seem to grasp how to say: "Ok, it's 8:03am, I need to remove 8 hours and 2 minutes which will put me at 12:01am".
Start with some date of today, for example "now":
NSCalendar *cal = [NSCalendar currentCalendar];
NSDate *now = [NSDate date];
Subtract one day to get some date of yesterday:
NSDateComponents *minusOneDay = [[NSDateComponents alloc] init];
[oneDay setDay:-1];
NSDate *nowMinusOneDay = [cal dateByAddingComponents:minusOneDay toDate:now options:0];
Compute start and end date of the "day calendar unit" that contains yesterday's date:
NSDate *startOfYesterday;
NSTimeInterval lengthOfYesterday;
[cal rangeOfUnit:NSDayCalendarUnit startDate:&startOfYesterday interval:&lengthOfYesterday forDate:nowMinusOneDay];
NSDate *endOfYesterday = [startOfYesterday dateByAddingTimeInterval:lengthOfYesterday];
This should work even if a daylight savings time transition occurs between today and yesterday.
Generally one should avoid to use explicit time intervals such as "24 hours", because not every day has that length.
I have the simplest of tasks that I can't figure out how to do correctly. With the snippet below I can find out the beginning of a month.
NSCalendar *cal = [NSCalendar currentCalendar];
NSDate *beginning = nil;
[cal rangeOfUnit:NSMonthCalendarUnit startDate:&beginning interval:NULL forDate:self];
return beginning;
Now I want to determine the end of that same month (the last second at 23:59:59 would suit my purposes). My first thought was to start at the first day of the next month and subtract a second. But I couldn't break down the date in an NSDateComponent instance to [dateComponents setMonth:[dateComponents month] + 1], because in the case of December that method wouldn't accept 12 + 1 = 13 to get to January, right?
Then how would I get to the last second of a month?
Do this to get the beginning of next month:
NSDateComponents *comps = [[NSDateComponents alloc] init];
[comps setMonth:1];
NSDate *beginningOfNextMonth = [cal dateByAddingComponents:comps toDate:beginning options:0];
[comps release];
Alright, I think I have it. I'm using the rangeOfUnit:inUnit:forDate: method to determine the length of the current month in days, and add the corresponding NSTimeInterval to the month's start date.
- (NSDate *)firstSecondOfTheMonth {
NSCalendar *cal = [NSCalendar currentCalendar];
NSDate *beginning = nil;
if ([cal rangeOfUnit:NSMonthCalendarUnit startDate:&beginning interval:NULL forDate:self])
return beginning;
return nil;
}
- (NSDate *)lastSecondOfTheMonth {
NSDate *date = [self firstSecondOfTheMonth];
NSCalendar *cal = [NSCalendar currentCalendar];
NSRange month = [cal rangeOfUnit:NSDayCalendarUnit inUnit:NSMonthCalendarUnit forDate:date];
return [date dateByAddingTimeInterval:month.length * 24 * 60 * 60 - 1];
}
Note: Although this code works as I intended it to work, the answer that #spacehunt gave more clearly communicates the purpose.
The last second of the month... Most of the time, that boils down to taking the first second of the next month, and subtracting one second.
But are you asking the right question? What's the meaning of that last second? My guess is that you want to express a time interval starting from (and including) the first second of month N, and ending right before the first second of month N+1.
I would like to know the dates of all Monday's in a month using NSCalendar in Objective-C. So Please help me.
Thanks in advance
I blogged a solution for this a few months ago
http://brandontreb.com/case-of-the-mondays/
From https://discussions.apple.com/thread/1700102?start=0&tstart=0 and the Apple NSCalendar reference:
How about using something like this -
NSDateComponents *comps = [[NSDateComponents alloc] init];
[comps setYear:1965]; // Year of the calendar month
[comps setMonth:1]; // Month
[comps setDay:6]; // Any day
NSDate *date = [gregorian dateFromComponents:comps];
[comps release];
Then, once you have the NSDate, do this:
NSDate * testDate = [NSDate date];
NSString * weekdayString = [testDate descriptionWithCalendarFormat:#"%A" timeZone:nil
locale:[[NSUserDefaults standardUserDefaults] dictionaryRepresentation]];
NSLog(#"Day of the week: %#", weekdayString);
// weekdayString should look like "Monday", etc.
So, you can loop through the month's days until;
[weekdayString isEqualToString:#"Monday"] // or your desired day
And then just add 7 days to get the other 4 or so dates.
This may not be the prettiest solution, but it should work.