Swift Custom NSMutableArray Sorting - ios

Question

I have a custom NSMutableArray and i want to sort it; I've looked over the internet but nothing solve my problem. what I have is the following Locations.swift
import UIKit
class Location: NSObject {
var id:String = String()
var name:String = String()
var distance:Float = Float()
}
then I create a Mutable Array from this class in my ViewController.swift
class CustomViewController: UIViewController{
var locations: NSMutableArray!
override func viewDidLoad() {
super.viewDidLoad()
locations = NSMutableArray()
locations = SqLite.getInstnace().getLocations()//get values from DB، objects of Location
}
}
how I can sort locations by the distance value??

Answer 1

I would make location an array of Location objects, and then sorting becomes easy with sortInPlace.
class CustomViewController: UIViewController{
var locations = [Location]()
override func viewDidLoad() {
super.viewDidLoad()
locations = SqLite.getInstnace().getLocations().flatMap { $0 as? Location }
}
}
Now you can sort locations like this:
locations.sortInPlace { $0.distance < $1.distance }

Answer 2

You could always use the built in sort function:
let locations = SqLite.getInstnace().getLocations().sort({
return ($0 as! Location).distance < ($1 as! Location).distance
})
if SqLite.getInstnace().getLocations() return an array as [Location] and not a NSArray then you could just do this since it will already know the elements types:
let locations = SqLite.getInstnace().getLocations().sort({
return $0.distance < $1.distance
})
This should return a sorted array in ascending order if you want descending just use > instead.
Also, there is really no need to use NSMutableArrays in Swift. Just use [Location].
Edit:
NSMutableArray can be used in swift but it considered objective-c like where as using [OBJECT_TYPE] is conventional for swift.
Take a look at the Swift 2 book array segment. None of the examples use NSArray or NSMutable array.
By declaring something with var in swift makes it mutable where as let makes something immutable