ios - 无法弄清楚如何使用 CLPlacemark 将我的当前位置正确地嵌入到消息正文中

Question

几天前我几乎没有尝试在我的 iPhone 上的消息正文中嵌入我的当前位置，但我失败了。

我想尽了所有办法，但我只得到了错误

我得到的最后一个错误是

"fatal error: unexpectedly found nil while unwrapping an Optional value"

我创建了一个 CLPlacemark 的对象，并将其设为可选，这意味着它可以有值也可以为 nil。

有什么方法可以用我当前的位置创建消息吗？

主菜单文件

import UIKit
import Social
import MessageUI
import Foundation
import CoreLocation


class MainMenu: UIViewController , MFMessageComposeViewControllerDelegate , UINavigationControllerDelegate , MFMailComposeViewControllerDelegate, CLLocationManagerDelegate {

    let locationManager = CLLocationManager()

    func messageComposeViewController(controller: MFMessageComposeViewController, didFinishWithResult result: MessageComposeResult) {
    }

    let placeMarks = Location()

    @IBAction func TapOnEmergency(sender: UIButton) {

       let textMessageRecipients = ["+123456789"]

       let messageComposer = MFMessageComposeViewController()

       let Emergency  = UIAlertController(title: "Do You Need Help ?", message: nil, preferredStyle: UIAlertControllerStyle.ActionSheet)

       let Yes = UIAlertAction(title: "YES", style: .Default) { (action) in

            if (MFMessageComposeViewController.canSendText()) {

                messageComposer.messageComposeDelegate = self
                messageComposer.recipients = textMessageRecipients

                messageComposer.body = "I'm Lost, I need some Help, Here's my Location \(self.placeMarks.currentLocation!.country)"

                self.navigationController?.presentViewController(messageComposer, animated: true){}
                self.presentViewController(messageComposer, animated: true, completion: nil)
                self.messageComposeViewController(messageComposer, didFinishWithResult: MessageComposeResultCancelled)



            } else {

                let errorAlert = UIAlertController(title: "Cannot Send Text Message", message: "Your device is not able to send text messages.", preferredStyle: UIAlertControllerStyle.Alert)

                            errorAlert.addAction(UIAlertAction(title: "OK", style: UIAlertActionStyle.Cancel, handler: nil))

                            self.presentViewController(errorAlert, animated: true, completion: nil)

            }



            let Options  = UIAlertController(title: "Do You Want to Call Your Supervisor ?", message: nil, preferredStyle: UIAlertControllerStyle.ActionSheet)

            let dialNumber = UIAlertAction(title: "YES", style: .Default) { (action) in

            let call:NSURL = NSURL(string: "tel://123456789")!
            UIApplication.sharedApplication().openURL(call)

            }

            Options.addAction(dialNumber)

            let Dismiss = UIAlertAction(title: "Dismiss", style: .Destructive) { (action) in

            }

            Options.addAction(Dismiss)


            self.presentViewController(Options, animated: true) {}


        }

        Emergency.addAction(Yes)

        let No = UIAlertAction(title: "Dismiss", style: .Destructive) { (action) in

        }

        Emergency.addAction(No)

        self.presentViewController(Emergency, animated: true) {}

    }
}

定位文件

import UIKit
import CoreLocation

class Location: UIViewController, CLLocationManagerDelegate {

    let locationManager = CLLocationManager()
    var currentLocation : CLPlacemark?
}

Answer 1

只是创建 CLPlacemark 不会为您获取位置。您将必须创建 CLLocationManager 对象，然后使用 CLLocationManager 对象的 startUpdatingLocation 方法更新您的当前位置。此外，您还必须实现委托(delegate)方法以通过这种方式接收当前位置。

import UIKit
import CoreLocation

class Location: UIViewController, CLLocationManagerDelegate {

    let locationManager = CLLocationManager()
    var currentLocation : CLPlacemark?
    var locationManager = CLLocationManager()

    private override init() {
        super.init()
        locationManager.delegate = self
    }
    func updateLocation()
    {
        locationManager.startUpdatingLocation()
    }
    func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        locationManager.stopUpdatingLocation()
        let location  : CLLocation = locations.last as CLLocation!
        //use reverse geocoding to get the address from location coordinates you got
    }

}

获得位置坐标后，您可以进行反向地理编码以获取地标或确切地址。引用Reverse Geocode Location in Swift用于反向地理编码。关于您遇到的错误，您可以在创建消息之前检查地点标记对象是否为 nil。