Google geocoding - ios

Question

Thanks for the tremendous helps, I was able to get lat and lng by using Google geocoding API with swift. If anyone encounters some problems, hope this helps!
here is the code.
var components = URLComponents(string: "https://maps.googleapis.com/maps/api/geocode/json")!
let key = URLQueryItem(name: "key", value: "YOUR_KEY")
let address = URLQueryItem(name: "address", value: TOKYO)
components.queryItems = [key, address]
let task = URLSession.shared.dataTask(with: components.url!) { data, response, error in
guard let data = data, let httpResponse = response as? HTTPURLResponse, httpResponse.statusCode == 200, error == nil else {
print(String(describing: response))
print(String(describing: error))
return
}
guard let json = try! JSONSerialization.jsonObject(with: data) as? [String: Any] else {
print("not JSON format expected")
print(String(data: data, encoding: .utf8) ?? "Not string?!?")
return
}
guard let results = json["results"] as? [[String: Any]],
let geometry = results[0]["geometry"] as? [String:AnyObject],
let location = geometry["location"] as? [String:Double],
let lat = location["lat"],
let lng = location["lng"],
let status = json["status"] as? String,
status == "OK"
else{return}

Answer 1

Check this out:
var components = URLComponents(string: "https://maps.googleapis.com/maps/api/geocode/json")!
let key = URLQueryItem(name: "key", value: "AIzaSyCbFUri87RMHBX42AsOuxDQANeDCCK8LkA") // use your key
let address = URLQueryItem(name: "address", value: "Tokyo")
components.queryItems = [key, address]
let task = URLSession.shared.dataTask(with: components.url!) { data, response, error in
guard let data = data, let httpResponse = response as? HTTPURLResponse, httpResponse.statusCode == 200, error == nil else {
print(String(describing: response))
print(String(describing: error))
return
}
guard let json = try! JSONSerialization.jsonObject(with: data) as? [String: Any] else {
print("not JSON format expected")
print(String(data: data, encoding: .utf8) ?? "Not string?!?")
return
}
guard let results = json["results"] as? [[String: Any]],
let status = json["status"] as? String,
status == "OK" else {
print("no results")
print(String(describing: json))
return
}
}
task.resume()

Answer 2

Take a look at,
stringByAddingPercentEscapesUsingEncoding
for ios 8 and prior.
from ios 9,
stringByAddingPercentEncodingWithAllowedCharacters
Your code should be like,
let jsonUrl = "https://maps.googleapis.com/maps/api/geocode/json?address=Tokyo&key=Mykey"
let yourFinalString = jsonUrl.addingPercentEncoding(withAllowedCharacters: .urlHostAllowed)
guard URL(string:yourFinalString!) != nil else {
return print("error")
}
If your url string have some special characters then you have to escapes it by utf8 encoding!

Answer 3

For constructing URLs with query params I recommend to use URLComponents:
var constructor = URLComponents()
constructor.scheme = "https"
constructor.host = "maps.googleapis.com"
constructor.path = "/maps/api/geocode/json"
constructor.queryItems = [
URLQueryItem(name: "address", value: "Tokyo"),
URLQueryItem(name: "key", value: "MyKey")
]
constructor.url // https://maps.googleapis.com/maps/api/geocode/json?address=Tokyo&key=MyKey
or
var constructor = URLComponents(string: "https://maps.googleapis.com/maps/api/geocode/json")
constructor?.queryItems = [
URLQueryItem(name: "address", value: "Tokyo"),
URLQueryItem(name: "key", value: "MyKey")
]
constructor?.url // https://maps.googleapis.com/maps/api/geocode/json?address=Tokyo&key=MyKey
It will format and escape all the characters internally, using proper allowed characters list.