如何在调用另一个方法之前等待 didUpdateLocations 方法被调用？

Question

我正在开发一个应用程序，我想在用户注册时存储用户的当前位置。

因此，只要用户单击注册按钮，就会调用 locationManager.startUpdatingLocation()，然后执行注册操作。

但是，即使在 didUpdateLocations 委托方法 returns 之前，也会触发注册方法的坐标，因此用户的位置在数据库中存储为 nil。

尝试在 didUpdateLocations 中调用注册方法是一团糟，因为这个委托被调用了多次。

    func signup() { 
        self.getLocation()
        let point = PFGeoPoint(latitude:locationLat, longitude:locationLon)
        ...
        newUser[PF_USER_LOCATION] = point
        newUser.signUpInBackground(block: { (succeed, error) -> Void in

            if let errorInSignup = error {
                ...    
            } else {
                ...
            }
        })
    }

    func getLocation() {
        if CLLocationManager.locationServicesEnabled() {            
            locationManager.delegate = self
            locationManager.desiredAccuracy = kCLLocationAccuracyBest
            locationManager.startUpdatingLocation()
        }
    }

    func locationManager(_ manager: CLLocationManager, didUpdateLocations  locations: [CLLocation]) {

        let locValue:CLLocationCoordinate2D = manager.location!.coordinate

        locationLat = locValue.latitude
        locationLon = locValue.latitude
    }

我只添加了部分代码。

等待收到坐标调用注册函数的正确程序是什么？

requestWhenInUseAuthorisation()在viewDidLoad()

里面

Answer 1

喜欢

func signup() { 
        self.getLocation()

    }

在这里打电话

   func locationManager(_ manager: CLLocationManager, didUpdateLocations  locations: [CLLocation]) {
          manager.stoptUpdatingLocation() // initialy stop updation
        let locValue:CLLocationCoordinate2D = manager.location!.coordinate

        locationLat = locValue.latitude
        locationLon = locValue.latitude
         let point = PFGeoPoint(latitude:locationLat, longitude:locationLon)
        ...
        newUser[PF_USER_LOCATION] = point
        newUser.signUpInBackground(block: { (succeed, error) -> Void in

            if let errorInSignup = error {
                ...    
            } else {
                ...
                // call your main view
            }
        })
    }

如何在调用另一个方法之前等待 didUpdateLocations 方法被调用？

How to wait for didUpdateLocation method to be called before calling another method?

asynchronous

cllocationmanager

ios

swift