How to sort date? - ios

Question

i have array Like :
<__NSArrayM 0x79f3a4a0>(
{
"act_date" = "02/03/2015";
"act_id" = 3;
"act_name" = test2;
},
{
"act_date" = "03/03/2015";
"act_id" = 4;
"act_name" = test3;
},
{
"act_date" = "01/03/2015";
"act_id" = 5;
"act_name" = test1;
}
)
i want to sort array with date.
i tried this method :
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:#"MM/dd/yyyy"];
NSMutableArray *tempArray = [NSMutableArray array];
for (NSString *dateString in tblList)
{
NSDate *date = [formatter dateFromString:[dateString valueForKey:#"act_date"]];
[tempArray addObject:date];
}
[tempArray sortUsingComparator:^NSComparisonResult(NSDate *date1, NSDate *date2) {
// return date2 compare date1 for descending. Or reverse the call for ascending.
return [date2 compare:date1];
}];
But it returns only array with date, how do I add my all data with sorted date array??

Answer 1

I would do this, if you need to convert the values of "act_date" to an proper NSDate before comparison:
NSDateFormatter *_dateFormatter = [[NSDateFormatter alloc] init];
[_dateFormatter setDateFormat:#"MM/dd/yyyy"];
NSArray *_yourOriginalArray = // ...
NSArray *_sortedArray = [_yourOriginalArray sortedArrayUsingComparator:^NSComparisonResult(NSDictionary * obj1, NSDictionary * obj2) {
return [[_dateFormatter dateFromString:[obj2 valueForKey:#"act_date"]] compare:[_dateFormatter dateFromString:[obj1 valueForKey:#"act_date"]]];
}];
then the _sortedArray will have the items sorted.

Answer 2

You are taking out Date from your array, it is not need, you can still sort array of dictionary by using method like below.
NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:#"act_date" ascending:YES];
NSArray *sortedArray = [tblList sortedArrayUsingDescriptors:#[sortDescriptor]];

Answer 3

You can use a simple NSSortDescriptor
NSSortDescriptor * sortDescriptor = [[NSSortDescriptor alloc] initWithKey:#"act_date" ascending:YES selector:#selector(compare:)];
array = [array sortedArrayUsingDescriptors:#[sortDescriptor]];
If you want you can add more descriptor to sort for instance by act_id. The priority is set by the oreder of sort descriptors in the array that you pass to the method -sortUsingDescriptor
[EDIT]
As pointed out by holex act_date is a string and it should be converted to NSdate by using NSDateFormatter. Or you will just sort strings.

Answer 4

I am sorting an array of dictionaries with date-
NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:#"act_date" ascending:NO];
[mArrTimeline sortUsingDescriptors:[NSArray arrayWithObject:sortDescriptor]];

Answer 5

Try this code. May be useful to you.
NSString *strKey = #"act_date";
NSSortDescriptor *sortByName = [NSSortDescriptor sortDescriptorWithKey:strKey ascending:YES];
NSArray *sortDescriptors = [NSArray arrayWithObject:sortByName];
tempArr = (NSMutableArray *)[arr sortedArrayUsingDescriptors:sortDescriptors];