在Firestore Swift中在Google地图上显示多个位置

Question

我正在尝试在Google地图上显示位置，我从Firestore获取了经度和纬度。

我创建了一个存储纬度和经度的结构

struct Location {

var latitude: String = ""
var longitute: String = ""
}

这是我的firestore代码，用于获取经度和纬度

for document in snapshot!.documents {
self.location.append(Location(latitude: "\(document.data()["Latitude"] ?? "")", longitute: "\(document.data()["longitude"] ?? "")"))
print(self.location)

    guard let long = document.data()["Latitude"] as? String else { return}
    guard let lat = document.data()["longitude"] as? String else { return}
    let markerStart = GMSMarker(position: CLLocationCoordinate2D(latitude: Double(long) ?? 0.0, longitude: Double(lat) ?? 0.0))
    markerStart.map = self.mapView
}

我正在控制台中找到位置，但是当我将其转换为Doubles并试图在Google地图上显示时，它无法正常工作。请帮忙吗？

 Document Value is ["userid": 24xDkrtBV6cJrBvRD3U0PmyBF3o2, "createddatetime": FIRTimestamp: seconds=1546584489 nanoseconds=461000000>, "user_role": sales man, "Latitude": 20.6108261, "longitude": 72.9269003, "batterypercentage": 66, "name": Keyur , "company_code": 001]

Answer 1

所以您有以下数据：

["userid": 24xDkrtBV6cJrBvRD3U0PmyBF3o2, "createddatetime": FIRTimestamp: seconds=1546584489 nanoseconds=461000000>, "user_role": sales man, "Latitude": 20.6108261, "longitude": 72.9269003, "batterypercentage": 66, "name": Keyur , "company_code": 001]

代替这种代码：

for document in snapshot!.documents {
self.location.append(Location(latitude: "\(document.data()["Latitude"] ?? "")", longitute: "\(document.data()["longitude"] ?? "")"))
print(self.location)

    guard let long = document.data()["Latitude"] as? String else { return}
    guard let lat = document.data()["longitude"] as? String else { return}
    let markerStart = GMSMarker(position: CLLocationCoordinate2D(latitude: Double(long) ?? 0.0, longitude: Double(lat) ?? 0.0))
    markerStart.map = self.mapView
}

我们可以像这样改善它

    for document in snapshot!.documents {
        self.location.append(Location(latitude: "\(document.data()["Latitude"] ?? "")", longitute: "\(document.data()["longitude"] ?? "")"))
        print(self.location)

        guard let latitude = document.data()["Latitude"] as? Double,
            let longitude = document.data()["Latitude"] as? Double else { return }

        let markerStart = GMSMarker(position: CLLocationCoordinate2D(latitude: latitude, longitude: longitude)
        markerStart.map = self.mapView
    }

程序未到达第72 73 74行的原因是由于guard let。无法将您假设的String的经纬度从Double转换为document.data()。像我上面的代码一样做，然后您可以根据需要进一步改进它。