Swift Firebase按距离排序
我想按距离排序我的数组。我已经拥有了一切能够抓住距离的东西,但不确定如何从最接近最远的用户位置进行排序。我已经使用MKMapItem的下面的代码,但不确定如何应用到我当前的数组。Swift Firebase按距离排序
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!)
})
}
火力地堡呼叫
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)
}
}
首先要在你的代码中的这些变化
singleChildDictionary["distanceInMiles"] = distanceInMiles
然后你就可以像这样对它进行排序:
self.usersArray = self.usersArray.sorted {
!($0["distanceInMiles"] as! Double > $1["distanceInMiles"] as! Double)
}
我会在哪里申报呢?在通话中? –
我猜测第二部分可能是一个函数,可以放在文件的任何位置? –
@LukasBimba添加第一行之后singleChildDictionary [“distanceLabelText”] = distanceLabelText如AnyObject然后self.usersArray.append(singleChildDictionary作为NSDictionary的)后添加第二部分的xcode – 3stud1ant3
所以你要对我们进行排序根据distanceLabelText ersArray? – 3stud1ant3
是的,这将是完美的 –
你想在哪里排序usersArray,为什么? – 3stud1ant3