Can i sort a Array in Swift with custom logic for sorting

Question

I have been through almost all question of stackoverflow regarding it's answer where it says

array.sort({
    $0.name < $1.name
})

But I do not want this at all...

I have Array containing custom objects and I want to sort it as per it's one of the variable name status ... but not is ascending or descending order ... that sorting depends on the status...

Here is the equivalent Objective C code

@interface NSString (StatusComparison)
- (NSComparisonResult)statusCompare:(NSString*)otherStatus;
@end
@implementation NSString (WeekdayComparison)
- (NSComparisonResult)statusCompare:(NSString*)otherDay {

NSArray *allStatus = [NSArray arrayWithObjects:@"Immediate",@"Near",@"Far",@"Unknown",ENTER_IN_REGION,EXIT_REGION,START_MONITORING,FAIL,NOT_STARTED, nil];

    NSUInteger selfIndex = [allStatus indexOfObject:self];
    NSUInteger otherDayIndex = [allStatus indexOfObject:otherDay];

    if (selfIndex < otherDayIndex) {
        return NSOrderedAscending;
    }
    else if (selfIndex > otherDayIndex) {
        return NSOrderedDescending;
    } else {
        return NSOrderedSame;
    }
}
@end

NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"status" ascending:YES selector:@selector(statusCompare:)];
NSArray *sortDescriptors = [NSArray arrayWithObjects:sortDescriptor, nil];
self.dataArray = [self.dataArray sortedArrayUsingDescriptors:sortDescriptors];

How can I do the same thing in Swift. Please read the entire question before marking it as duplicate... It's not duplicate

This still is a duplicate. I cannot see how this is any different, except you're using a custom ordering for sorting. What is the point that does not make this a dup? — Tobi Nary
– Tobi Nary, Commented Nov 25, 2015 at 12:09
You can not use that < > logic here ... it doesn't solve the problem ... solution of the problem is in the answers given below ... which differes from generic answer — Mihir Mehta
– Mihir Mehta, Commented Nov 25, 2015 at 13:28
Yes, you can. And the answer below does, too. And no, it does not differ from the generic answer 'use code to describe the order you'd like to impose'. — Tobi Nary
– Tobi Nary, Commented Nov 25, 2015 at 13:34
@JanGreve yes i got it ... but the indexOf thing was not generic and i was missing tht... which i couldn't find anywhere else — Mihir Mehta
– Mihir Mehta, Commented Nov 25, 2015 at 13:59

vadian · Accepted Answer · 2015-11-25 12:59:42Z

3

The Swift equivalent is

dataArray.sortInPlace {
  return allStatus.indexOf($0.status)! < allStatus.indexOf($1.status)!
}

The allStatus array could be declared in the sort closure as well as somewhere in global scope or before the closure in local scope.

In Swift it might be preferable to declare the allStatus contents as enum type with Int raw value type and the status property in your custom class as the enum type. The benefit is a predictable number of cases and no potential optionals.

For example

enum Status : Int {
  case Immediate = 0, Near, Far, Unknown, FAIL
  var stringValue : String  { return String(self) }
}


dataArray.sortInPlace {
  return $0.status.rawValue < $1.status.rawValue
}

You can still get the string representation of the enum cases with

dataArray[0].status.stringValue

edited Nov 25, 2015 at 12:59

answered Nov 25, 2015 at 12:26

vadian

286k32 gold badges378 silver badges379 bronze badges

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

Comments

sunshinejr · Accepted Answer · 2015-11-25 12:24:58Z

0

Simple example in Swift would be:

["Near", "Immediate", "Far"].sort { (status1, status2) in
    let statuses = ["Immediate", "Near", "Far", "Unknown"]
    guard let index1 = statuses.indexOf(status1), index2 = statuses.indexOf(status2) else {
        return false
    }

    return index1 < index2
} // Prints ["Immediate", "Near", "Far"]

answered Nov 25, 2015 at 12:24

sunshinejr

4,8442 gold badges24 silver badges32 bronze badges

Comments

Samurai Girl · Accepted Answer · 2015-11-25 12:10:20Z

-1

array.sort({
    $0.name < $1.name 
})

This is just a short hand for passing closure as an argument. You can have a complete function with two arguments, which you can pass to this sort method.

Have a look at this Swift closures

answered Nov 25, 2015 at 12:10

Samurai Girl

9982 gold badges8 silver badges13 bronze badges

Collectives™ on Stack Overflow

Can i sort a Array in Swift with custom logic for sorting

3 Answers 3

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related