iOS CLLocationManager 在一个单独的类中

Question

我有多个需要获取用户位置的视图控制器，所以我想创建一个单独的类，视图控制器可以调用该类来获取用户的最新位置。

locationManager:didUpdateToLocation:fromLocation 返回 void。计算出用户的经纬度后，如何将经纬度数据传回 ViewController？

我可以尝试在我的 locationManaging 类中编写 getter 和 setter，但如果我这样做了，我怎么知道何时从我的 ViewController 类中调用 latitude getter 和 longitude getter 方法？如何让 ViewController 的主线程等待来自 locationManaging 类的纬度和经度值？

谢谢！

Answer 1

正如 user1071136 所说，单例位置管理器可能是您想要的。创建一个类，一个 NSObject 的子类，只有一个属性，CLLocationManager。

LocationManagerSingleton.h：

#import <MapKit/MapKit.h>

@interface LocationManagerSingleton : NSObject <CLLocationManagerDelegate>

@property (nonatomic, strong) CLLocationManager* locationManager;

+ (LocationManagerSingleton*)sharedSingleton;

@end

LocationManagerSingleton.m：

#import "LocationManagerSingleton.h"

@implementation LocationManagerSingleton

@synthesize locationManager;

- (id)init {
    self = [super init];

    if(self) {
        self.locationManager = [CLLocationManager new];
        [self.locationManager setDelegate:self];
        [self.locationManager setDistanceFilter:kCLDistanceFilterNone];
        [self.locationManager setHeadingFilter:kCLHeadingFilterNone];
        [self.locationManager startUpdatingLocation];
        //do any more customization to your location manager
    }

    return self;
}    

+ (LocationManagerSingleton*)sharedSingleton {
    static LocationManagerSingleton* sharedSingleton;
    if(!sharedSingleton) {
        static dispatch_once_t onceToken;
        dispatch_once(&onceToken, ^{
            sharedSingleton = [LocationManagerSingleton new];
        }
    }

    return sharedSingleton;
}

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation {
    //handle your location updates here
}

- (void)locationManager:(CLLocationManager *)manager didUpdateHeading:(CLHeading *)newHeading {
    //handle your heading updates here- I would suggest only handling the nth update, because they
    //come in fast and furious and it takes a lot of processing power to handle all of them
}

@end

要获取最近收到的位置，只需使用[LocationManagerSingleton sharedSingleton].locationManager.location。预热 GPS 可能需要几秒钟才能获得准确的位置。

Answer 2

创建一个具有latitude 和longitude 属性、startLocating 和endLocating 的单例类。在类中，创建一个CLLocationManager 实例，并将其委托设置为单例。在startLocating 和endLocating 中，调用CLLocationManager 实例的相应方法。使委托方法更新latitude 和longitude 属性。在其他ViewControllers 中，请阅读此单例的latitude 和longitude 属性。

要知道何时从另一个 ViewController 读取这些属性，请在这些属性上设置观察者（请参阅 NSKeyValueObserving Protocol Reference

在执行此操作之前，请在 Internet 上查找现有代码。

完成此操作后，使用许可许可证将其上传到 GitHub。

Answer 3

根据上面的答案，这是我所做的，你可以在github上找到完整的例子https://github.com/irfanlone/CLLocationManager-Singleton-Swift

只需将此文件导入您的项目，然后您可以选择实施 LocationUpdateProtocol 或收听位置更新通知

import MapKit

protocol LocationUpdateProtocol {
    func locationDidUpdateToLocation(location : CLLocation)
}

/// Notification on update of location. UserInfo contains CLLocation for key "location"
let kLocationDidChangeNotification = "LocationDidChangeNotification"

class UserLocationManager: NSObject, CLLocationManagerDelegate {

    static let SharedManager = UserLocationManager()

    private var locationManager = CLLocationManager()

    var currentLocation : CLLocation?

    var delegate : LocationUpdateProtocol!

    private override init () {
        super.init()
        self.locationManager.delegate = self
        self.locationManager.desiredAccuracy = kCLLocationAccuracyBest
        self.locationManager.distanceFilter = kCLLocationAccuracyHundredMeters
        locationManager.requestAlwaysAuthorization()
        self.locationManager.startUpdatingLocation()
    }

    // MARK: - CLLocationManagerDelegate

    func locationManager(manager: CLLocationManager, didUpdateToLocation newLocation: CLLocation, fromLocation oldLocation: CLLocation) {
        currentLocation = newLocation
        let userInfo : NSDictionary = ["location" : currentLocation!]

        dispatch_async(dispatch_get_main_queue()) { () -> Void in
            self.delegate.locationDidUpdateToLocation(self.currentLocation!)
            NSNotificationCenter.defaultCenter().postNotificationName(kLocationDidChangeNotification, object: self, userInfo: userInfo as [NSObject : AnyObject])
        }
    }

}

用法：

class ViewController: UIViewController, LocationUpdateProtocol {

    var currentLocation : CLLocation!

    override func viewDidLoad() {
        super.viewDidLoad()

        NSNotificationCenter.defaultCenter().addObserver(self, selector: "locationUpdateNotification:", name: kLocationDidChangeNotification, object: nil)

        let LocationMgr = UserLocationManager.SharedManager
        LocationMgr.delegate = self

    }

    // MARK: - Notifications

    func locationUpdateNotification(notification: NSNotification) {
        let userinfo = notification.userInfo
        self.currentLocation = userinfo!["location"] as! CLLocation
        print("Latitude : \(self.currentLocation.coordinate.latitude)")
        print("Longitude : \(self.currentLocation.coordinate.longitude)")

    }

    // MARK: - LocationUpdateProtocol

    func locationDidUpdateToLocation(location: CLLocation) {
        currentLocation = location
        print("Latitude : \(self.currentLocation.coordinate.latitude)")
        print("Longitude : \(self.currentLocation.coordinate.longitude)")
    }

}

Answer 4

这是我在 swift 中实现位置管理器单例时所做的。它基于user1071136的策略，以及this swift pattern。

//
//  UserLocationManager.swift
//
//  Use: call SharedUserLocation.currentLocation2d from any class


import MapKit

class UserLocation: NSObject, CLLocationManagerDelegate {

    var locationManager = CLLocationManager()

    // You can access the lat and long by calling:
    // currentLocation2d.latitude, etc

    var currentLocation2d:CLLocationCoordinate2D?


    class var manager: UserLocation {
        return SharedUserLocation
    }

    init () {
        super.init()
        if self.locationManager.respondsToSelector(Selector("requestAlwaysAuthorization")) {
            self.locationManager.requestWhenInUseAuthorization()
        }
        self.locationManager.delegate = self
        self.locationManager.desiredAccuracy = kCLLocationAccuracyBest
        self.locationManager.distanceFilter = 50
        self.locationManager.startUpdatingLocation()
    }

    func locationManager(manager: CLLocationManager!, didUpdateLocations locations: [AnyObject]!) {
        self.currentLocation2d = manager.location.coordinate

    }
}

let SharedUserLocation = UserLocation()

Answer 5

在学习单例类获取用户位置的过程中，我下载了这段代码https://github.com/irfanlone/CLLocationManager-Singleton-Swift。在使用它在 Xcode8.3.3 Swift 3 上运行后，我无法在调试控制台中获得任何输出。事实上，我什至无法显示这个位置授权 dlalog。我怀疑来自单例的数据没有传递给视图控制器，但我无法解决这个问题，你能看出什么问题吗？谢谢。

Swift 3 的更正代码是：

//The singleton:
import MapKit

protocol LocationUpdateProtocol {
func locationDidUpdateToLocation(_ location : CLLocation)
}

let kLocationDidChangeNotification = "LocationDidChangeNotification"

class UserLocationManager: NSObject, CLLocationManagerDelegate {

static let SharedManager = UserLocationManager()

fileprivate var locationManager = CLLocationManager()

var currentLocation : CLLocation?

var delegate : LocationUpdateProtocol!

fileprivate override init () {
    super.init()
    self.locationManager.delegate = self
    self.locationManager.desiredAccuracy = kCLLocationAccuracyBest
    self.locationManager.distanceFilter = kCLLocationAccuracyHundredMeters
    locationManager.requestAlwaysAuthorization()
    self.locationManager.startUpdatingLocation()
}

// MARK: - CLLocationManagerDelegate
func locationManager(manager: CLLocationManager,didUpdateToLocation newLocation: CLLocation, fromLocation oldLocation: CLLocation) {
    currentLocation = newLocation
    let userInfo : NSDictionary = ["location" : currentLocation!]


    DispatchQueue.main.async() { () -> Void in
        self.delegate.locationDidUpdateToLocation(self.currentLocation!)
        NotificationCenter.default.post(name: Notification.Name(kLocationDidChangeNotification), object: self, userInfo: userInfo as [NSObject : AnyObject])
    }
}

}



  // The ViewController
    import UIKit
    import CoreLocation

 class ViewController: UIViewController, LocationUpdateProtocol {

var currentLocation : CLLocation!

override func viewDidLoad() {
    super.viewDidLoad()

    NotificationCenter.default.addObserver(self, selector: #selector(ViewController.locationUpdateNotification(_:)), name: NSNotification.Name(rawValue: kLocationDidChangeNotification), object: nil)

    let LocationMgr = UserLocationManager.SharedManager
    LocationMgr.delegate = self

}

// MARK: - Notifications

func locationUpdateNotification(_ notification: Notification) {
    let userinfo = notification.userInfo
    self.currentLocation = userinfo!["location"] as! CLLocation
    print("Latitude : \(self.currentLocation.coordinate.latitude)")
    print("Longitude : \(self.currentLocation.coordinate.longitude)")

}

// MARK: - LocationUpdateProtocol

func locationDidUpdateToLocation(_ location: CLLocation) {
    currentLocation = location
    print("Latitude : \(self.currentLocation.coordinate.latitude)")
    print("Longitude : \(self.currentLocation.coordinate.longitude)")
}


}