Question

我正在使用swift开发应用程序，我必须将用户的当前位置与从JSON文件中获取的其他位置进行比较。然后我必须显示从用户位置开始的某个范围内的所有位置。这个范围我从一个UISlider。我的意思是当用户在滑块中选择25km时，应用程序必须确定当前用户的位置并显示此范围内的所有水果。

   import UIKit
   import SwiftyJSON
   import MapKit
   import CoreLocation


 class TableViewController: UITableViewController,CLLocationManagerDelegate {
 @IBOutlet weak var Bar: UIToolbar!


@IBOutlet weak var LabelTest: UILabel! // this is the slider value, I segue it from the previous viewcontroller
var manager = CLLocationManager()

struct Fruit {
    let name : String
    let location : CLLocation
    let imageURL : NSURL
    let description : String
}
var fruits = [Fruit]()


func parseFruits() {
    guard let url = NSBundle.mainBundle().URLForResource("cities", withExtension: "json"), jsonData = NSData(contentsOfURL: url) else {
        print("Error finding JSON File")
        return
    }

    let jsonObject = JSON(data: jsonData)

    let fruitArray = jsonObject["fruits"].arrayValue
    for aFruit in fruitArray {
       let name = aFruit["Name"].stringValue
        let latitude = city["Latitude"] as! Double
        let longitude = city["Longitude"] as! Double
        let location = CLLocation(latitude: latitude, longitude: longitude)
       let imageURL = aFruit["Picture"].stringValue
    let description = aFruit["Description"].stringValue

        let fruit = Fruit(name: name,location: location,imageURL: NSURL(string:imageURL)!, description: description )
        fruits.append(fruit)
    }

    self.tableView.reloadData()
}

override func viewDidLoad() {
    super.viewDidLoad()
    parseFruits()

    // Uncomment the following line to preserve selection between presentations
    // self.clearsSelectionOnViewWillAppear = false

    // Uncomment the following line to display an Edit button in the navigation bar for this view controller.
    // self.navigationItem.rightBarButtonItem = self.editButtonItem()
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

// MARK: - Table view data source

override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
    // #warning Incomplete implementation, return the number of sections
    return 1
}

override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return fruits.count
    }



override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
     let cell: TableViewCell = tableView.dequeueReusableCellWithIdentifier("Cell") as!  TableViewCell
     let fruit = fruits[indexPath.row]
    cell.CellTitle.text = fruit.name
    cell.CellDescription.text = fruit.description


    let image = UIImage(data: NSData(contentsOfURL:(string: fruit.imageURL))!)
    cell.CellImage.image = image

    return cell
          }

目前我不是在计算用户的当前位置而我没有比较它，如果有人能告诉我该怎么做，我会很高兴。

编辑：

   func CalculateDistance() {
    let userLocation = CLLocation(latitude: lat, longitude: long)
    let destinationLocation = CLLocation(latitude:latitude, longitude: longitude)// latitude and longitude from the json file
    let distance = userLocation.distanceFromLocation(destinationLocation)
}

Answer 1

如果要计算两个位置之间的距离，可以执行以下操作：

let userLocation = CLLocation(latitude: lat, longitude: long)
let destinationLocation = CLLocation(latitude: (dest.lat as NSString).doubleValue, longitude: (dest.long as NSString).doubleValue)
let distance = userLocation.distanceFromLocation(destinationLocation)

获取userLocation，这是用户的当前位置。然后，您拥有目的地的位置，然后借助distanceFromLocation函数帮助计算距离，该CoreLocation函数是var distanceToFive = roundToFive(distance) private func roundToFive(x : Double) -> Int { return 5 * Int(round(x / 5.0)) }的一部分。

然后我做了一个方法，将距离四舍五入到最近的5米：

CLLocationManagerDelegate

您当然可以将此更改为10,20等。

修改：
并获得当前位置：
将var locationManager = CLLocationManager()添加到类继承中。声明viewDidLoad和两个变量一个用于lat，一个用于long。在self.locationManager.requestWhenInUseAuthorization() if CLLocationManager.locationServicesEnabled() { locationManager.delegate = self locationManager.desiredAccuracy = kCLLocationAccuracyBest }做

func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) { let location:CLLocationCoordinate2D = manager.location!.coordinate lat = location.latitude long = location.longitude } func locationManager(manager: CLLocationManager, didFailWithError error: NSError) { print("Error") }

然后获取用户的位置声明以下方法：

func CalculateDistance() -> Int{ let userLocation = CLLocation(latitude: lat, longitude: long) let destinationLocation = CLLocation(latitude:latitude, longitude: longitude)// latitude and longitude from the json file let distance = userLocation.distanceFromLocation(destinationLocation) return roundToFive(distance) } private func roundToFive(x : Double) -> Int { return 5 * Int(round(x / 5.0)) }

EDIT2：

data.frame

如何将用户当前位置与其他位置进行比较并在UITable View中显示？

1 个答案: