How to sort based on date of custom object in NSArray...?

Question

I have an Array of custom objects. Say the object is called A and this has a property called timestamp.(This is of NSDate type.)

Now I need to get the objects A filtered in different arrays for (MOnth and Year as unique key).

I have been trying to use predicates but unable to figure out how to put it on date objects.

You can look at the image below to see where exactly I need to use it...

EDIT: Removing image.

very good question i follow your post for the answer...nice attempt :) — D-eptdeveloper
– D-eptdeveloper, Commented Sep 2, 2013 at 6:19

Shaffiulla Khan · Accepted Answer · 2013-09-02 06:23:30Z

4

Here is the Code snippet which can help you

NSArray *sortedArray = [unSortedArray  sortedArrayUsingComparator: ^NSComparisonResult(DateObj *id1, DateObj *id2) {
            if(id1.timeStamp < id2.timeStamp)
                return YES;
            else
                return NO;
        }];

answered Sep 2, 2013 at 6:23

Shaffiulla Khan

10.4k16 gold badges58 silver badges54 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

Ankit Srivastava Over a year ago

This will just sort it but it will not return the unique combination of (month and year)

Martin R Over a year ago

Sorry, but this answer is wrong. 1) You cannot compare NSDate objects with <. 2) A comparator must return NSOrderedAscending (-1), NSOrderedSame (0), or NSOrderedDescending (+1), not YES or NO. - The question explicitly states "... timestamp. (This is of NSDate type.)".

Martin R Over a year ago

@ShafKhan: Even if timestamp is scalar property so that you can compare with <: Returning only YES or NO from a comparator is wrong. Have a look at the documentation of NSComparisonResult.

Martin R Over a year ago

@ShafKhan: "As NSDate timestamp returns NSTimeInterval"?? - NSDate does not have a timestamp method.

Andrey Gordeev · Accepted Answer · 2013-09-02 06:24:29Z

2

This should work:

[myArray sortUsingDescriptors:[NSArray arrayWithObject:
                                  [[NSSortDescriptor alloc] initWithKey:@"timestamp" ascending:NO]]];

answered Sep 2, 2013 at 6:24

Andrey Gordeev

32.7k16 gold badges143 silver badges169 bronze badges

1 Comment

Ankit Srivastava Over a year ago

This will just sort it but it will not return the unique combination of (month and year).

Collectives™ on Stack Overflow

How to sort based on date of custom object in NSArray...?

2 Answers 2

4 Comments

1 Comment

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

4 Comments

1 Comment

Related