Question

嗨我想在用户点击注释时获取索引号。我有以下代码..

class ShopLocation: NSObject, MKAnnotation{

 var identifier = "Shop location"
 var title: String?
 var subtitle: String?
 var coordinate: CLLocationCoordinate2D

    init(name:String,lat:CLLocationDegrees,long:CLLocationDegrees,addInfo:String){
        title = name
        coordinate = CLLocationCoordinate2DMake(lat, long)
        subtitle = addInfo
    }

}
    class LocationList: NSObject {


        var shop = [ShopLocation]()

          override init(){
            shop += [ShopLocation(name:"t1", lat:35.673647,long:139.727686,addInfo:"info")]

            shop += [ShopLocation(name:"t2", lat:35.671928,long:139.760815,addInfo:"info")]

            shop += [ShopLocation(name:"t3", lat:35.713232,long:139.793467,addInfo:"info")]
    }

注释显示在地图上。我想获取索引，例如，如果t1被点击，我得到索引为1.

我不知道该怎么写

func mapView(_ mapView: MKMapView, didSelect view: MKAnnotationView) {
    LocationList().shop.index(of: )

}

谢谢！

Answer 1

请尝试以下代码：

func mapView(_ mapView: MKMapView, didSelect view: MKAnnotationView) {
    guard let annotation = view.annotation else {
        return
    }
    for (index, item) in LocationList().shop.enumerated() {
        if let title = view.annotation?.title {
            if item.name! == title! {
                print(index)
                break
            }
        }
    }

Answer 2

我认为ShopLocation已经符合MKAnnotation，如果没有，那么请使其符合并将其传递给MKAnnotationView的初始化程序。这将通过delegate

在view.annotation方法中提供

既然您可以访问ShopLocation个实例，我会想到两个解决方案，可以在shop

中找到它的索引

符合Equatable - 这将启用index(of:)的{{1}}方法（实际上为Array Collection符合的Array

extension ShopLocation: Equatable {
    static func ==(lhs: ShopLocation, rhs: ShopLocation) -> Bool {
        // place here the conditions for two instances to be equal
    }

// ... later in the code

func mapView(_ mapView: MKMapView, didSelect view: MKAnnotationView) {
    guard let shopLocation = view.annotation as? ShopLocation else {
        // this early returns if the annotation is not a shop location,
        // if you don't wan't that you can use an if-let instead
        return
    }
    let index = LocationList().shop.index(of: shopLocation)
    // do what you need with the index
}

使用index(where:)的{{1}}方法（实际上是Array：）
```
Collection
```

就个人而言，我建议采用方法＃1，即使Apple建议将值类型符合Equatable。符合func mapView(_ mapView: MKMapView, didSelect view: MKAnnotationView) { guard let shopLocation = view.annotation as? ShopLocation else { // this early returns if the annotation is not a shop location, // if you don't wan't that you can use an if-let instead return } let index = LocationList().shop.index(where: { shopLocation in return // same conditions as for the Equatable }) // do what you need with the index }有助于减少代码，并支持除此处提到的Equatable之外的许多其他功能。

Answer 3

   func mapView(_ mapView: MKMapView, didSelect view: MKAnnotationView) {
        var index = shops.index(of: view.annotation! as! ShopLocation)!
    }

这份工作对我而言。

从注释中获取数组索引

3 个答案: