CODEWITHSUNDEEP
iosios7ios8
NullHypothesis
NullHypothesis

Reputation: 4506

Another pair of eyes for my date picking strategy?

I'd like to group dates for a given week, with the starting day being what the user chooses in their preferences. For example my preference may be that my work week starts on a Friday, and so Friday to Thursday should be my week. Sunday-Saturday. Monday-Sunday, etc.

So I'd like to present the user with a date picker, and although they can pick any calendar day, I'd like to have the collection of dates start with their starting day.

For example if I pick a random Wednesday next month, and my preferences are for a starting work week of Monday, then my collection of dates should start at Monday. The code must be able to walk backwards 2 days, find that monday, then walk forwards until Sunday.

My strategy was to do just that - loop backwards until the start date is found and simply add 6 days to end on a Saturday.

Before I go about it this way, is there a better way (or maybe some sort of specifics in iOS that would make this easier for me than somewhere else)?

Upvotes: 0

Views: 65

Answers (2)

zaph
zaph

Reputation: 112857

Examine the NSCalendar class. In particular is the method: setFirstWeekday:.

Example code:

NSDate *today = [NSDate date]; // Or a date of your choice
NSLog(@"today: %@", today);

NSCalendar *caledar = [NSCalendar currentCalendar];
[caledar setFirstWeekday:5]; // Sunday is 1
NSDate *beginningOfWeek;
[caledar rangeOfUnit:NSWeekCalendarUnit
           startDate:&beginningOfWeek
            interval:NULL
             forDate:today];
NSLog(@"beginningOfWeek: %@", beginningOfWeek);

NSLog output:

today: 2014-07-22 14:45:01 +0000
beginningOfWeek: 2014-07-17 04:00:00 +0000

Upvotes: 1

Austin
Austin

Reputation: 5655

Have you looked at NSDateComponents? You can specify a specific day of the week.

NSCalendar *calendar = [NSCalendar currentCalendar];
NSDateComponents *pickedDateComponents = [calendar components:NSCalendarUnitWeekday fromDate:pickedDate];
NSInteger saturday = 7; // In the Gregorian calendar, 1 is Sunday, 2 is Monday, etc..
NSDateComponents *daysUntilSaturdayComponents = [NSDateComponents new];
daysUntilSaturdayComponents.weekday = saturday - pickedDateComponents.weekday;
NSDate *saturdayAfterPickedDate = [calendar dateByAddingComponents:daysUntilSaturdayComponents toDate:pickedDate options:0];

Upvotes: 0

Related Questions