如何在Swift中的func中为全局常量创造价值

Question

How do I go about setting the long and latitude value (both which display a when app runs) to a global constant? The values are currently

String(format: "4.4f", latestLocation.coordinate.latitude) 

and

String(format: "4.4f", latestLocation.coordinate.longitude)

I want to make these a global constant like userlatitude and userlongitude which can be accessed outside the function. Do I have to return someHope that makes sense.

func locationManager(manager: CLLocationManager!,
    didUpdateLocations locations: [AnyObject]!)
{
    var latestLocation = locations.last as! CLLocation

    latitude.text = String(format: "%.4f",
        latestLocation.coordinate.latitude)
    longitude.text = String(format: "%.4f",
        latestLocation.coordinate.longitude)
}

Answer 1

This way you can store Locations to NSUserDefaults :

//First Convert it to NSNumber.
let lat : NSNumber = NSNumber(double: Location.latitude)
let lng : NSNumber = NSNumber(double: Location.longitude)

//Store it into Dictionary
let locationDict = ["lat": lat, "lng": lng]

//Store that Dictionary into NSUserDefaults
NSUserDefaults.standardUserDefaults().setObject(locationDict, forKey: "Location")

After that you can access it this way anywhere you want:

//Access that stored Values
let userLoc = NSUserDefaults.standardUserDefaults().objectForKey("Location") as! [String : NSNumber]

//Get user location from that Dictionary
let userLat = userLoc["lat"]
let userLng = userLoc["lng"]

var Annotation = MKPointAnnotation()

Annotation.coordinate.latitude = userLat as! CLLocationDegrees  //Convert NSNumber to CLLocationDegrees
Annotation.coordinate.longitude = userLng as! CLLocationDegrees //Convert NSNumber to CLLocationDegrees

Answer 2

1. Define your Variable Below of import statement. Something Like,

    import UIKit let latitude = 4.0 // Do Stuff - This Variable access in Any class. Thanx Swift.... 

2. Another solution is put your value in .plist/NSUser Default and access in every class(Where should you wish to use) using appropriate key.

Answer 3

One solution could be that you store the values as NSUserDefaults, which gives you access to the values when you need it. try this link for more information http://www.codingexplorer.com/nsuserdefaults-a-swift-introduction/