快速火力基地按距离排序

Question

我正在尝试按距离对数组进行排序。我已经将所有内容都连接起来以抓取距离，但不确定如何从用户位置从最近到最远进行排序。我已经将以下代码用于 MKMapItem，但不确定如何应用于我当前的数组。

func sortMapItems()  {
self.mapItems = self.mapItems.sorted(by: { (b, a) -> Bool in
return self.userLocation.location!.distance(from: a.placemark.location!) > self.userLocation.location!.distance(from: b.placemark.location!)
})
}

火力基地呼叫

databaseRef.child("Businesses").queryOrdered(byChild: "businessName").observe(.childAdded, with: { (snapshot) in
let key = snapshot.key
if(key == self.loggedInUser?.uid) {
print("Same as logged in user, so don't show!")
} else {
if let locationValue = snapshot.value as? [String: AnyObject] {
let lat = Double(locationValue["businessLatitude"] as! String)
let long = Double(locationValue["businessLongitude"] as! String)
let businessLocation = CLLocation(latitude: lat!, longitude: long!)
let latitude = self.locationManager.location?.coordinate.latitude
let longitude = self.locationManager.location?.coordinate.longitude
let userLocation = CLLocation(latitude: latitude!, longitude: longitude!)
let distanceInMeters : Double = userLocation.distance(from: businessLocation)
let distanceInMiles : Double = ((distanceInMeters.description as String).doubleValue * 0.00062137)
let distanceLabelText = "(distanceInMiles.string(2)) miles away"
var singleChildDictionary = locationValue
singleChildDictionary["distanceLabelText"] = distanceLabelText as AnyObject
self.usersArray.append(singleChildDictionary as NSDictionary)
/*
func sortMapItems()  {
self.mapItems = self.mapItems.sorted(by: { (b, a) -> Bool in
return self.userLocation.location!.distance(from: a.placemark.location!) > self.userLocation.location!.distance(from: b.placemark.location!)
})
}
*/
}

//insert the rows
self.followUsersTableView.insertRows(at: [IndexPath(row:self.usersArray.count-1,section:0)], with: UITableViewRowAnimation.automatic)
}
}) { (error) in
print(error.localizedDescription)
}
}

Answer 1

首先在代码中进行这些更改

singleChildDictionary["distanceInMiles"] = distanceInMiles

然后你可以这样排序：

self.usersArray = self.usersArray.sorted {
!($0["distanceInMiles"] as! Double > $1["distanceInMiles"] as! Double)
}