I'm trying to covert the address to respected latitude and longitude values i.e Geocoding.
From Google definition:
What is Geocoding?
Geocoding is the process of converting addresses (like "1600 Amphitheatre Parkway, Mountain View, CA") into geographic coordinates (like latitude 37.423021 and longitude -122.083739), which you can use to place markers or position the map.
I am trying the same in iOS using Swift.
My code is working fine. But some addresses are not converting into lat, lng values. I am sure the address I'm searching is 100% valid.
Here is my code
override func viewDidLoad() {
super.viewDidLoad()
var address = "Kloten Airport, Switzerland" // This Address not working
var geocoder = CLGeocoder()
geocoder.geocodeAddressString(address, {(placemarks: [AnyObject]!, error: NSError!) -> Void in
if let placemark = placemarks?[0] as? CLPlacemark {
let title = ABCreateStringWithAddressDictionary(placemark.addressDictionary, false)
println(title);
let location = CLLocationCoordinate2D(
latitude: placemark.location.coordinate.latitude,
longitude: placemark.location.coordinate.longitude
)
}
})
}
I tried different addresses to geocode like Houston USA (this worked well), "Rautistrasse 12" (this also worked well), but when I search the address Kloten Airport, Switzerland this not worked for me.
Is there any bug, in iOS geocodeAddressString, or something I'm doing wrong?
I think you are expecting the iOS geocoding to perform as well as Google's geocoding. It certainly won't, though.
It is not working because Apple's geocoding is not as good as Google's geocoding.
To see what I mean, put
Kloten Airport, Sweden
into the iOS Maps app. It gives nothing. Put it into maps.google.com and you see the airport.
Related
I posted this issue on GitHub, though it has been over a week and no response from the developers, so hoping to get an answer here.
Using the example code, plus adding a bit to show placemarks returned from ForwardGeocodeOptions, I came up with this testing code:
(Swift 3, Xcode 8)
func mapView(_ mapView: MGLMapView, regionDidChangeAnimated animated: Bool) {
geocodingDataTask?.cancel()
self.outputText.text = ""
// Variables.userLat and Variables.userLng are set through locationManager
let options = ReverseGeocodeOptions(coordinate: CLLocationCoordinate2D(latitude: Variables.userLat, longitude: Variables.userLng))
geocodingDataTask = geocoder.geocode(options) { [unowned self] (placemarks, attribution, error) in
if let error = error {
NSLog("%#", error)
} else if let placemarks = placemarks, !placemarks.isEmpty {
self.resultsLabel.text = placemarks[0].qualifiedName
let foptions = ForwardGeocodeOptions(query: self.inputText.text!)
// To refine the search, you can set various properties on the options object.
foptions.allowedISOCountryCodes = ["US"]
foptions.focalLocation = CLLocation(latitude: Variables.userLat, longitude: Variables.userLng)
let neLat = Variables.userLat + 1.0
let neLng = Variables.userLng + 1.0
foptions.allowedRegion?.northEast = CLLocationCoordinate2D(latitude: neLat, longitude: neLng)
let swLat = Variables.userLat - 1.0
let swLng = Variables.userLng - 1.0
foptions.allowedRegion?.southWest = CLLocationCoordinate2D(latitude: swLat, longitude: swLng)
foptions.allowedScopes = [.address, .pointOfInterest]
let _ = geocoder.geocode(foptions) { (placemarks, attribution, error) in
guard let placemark = placemarks?.first else {
return
}
let coordinate = placemark.location.coordinate
print("\(coordinate.latitude), \(coordinate.longitude)")
self.inputLat.text = coordinate.latitude.description
self.inputLng.text = coordinate.longitude.description
var string = ""
for mark in placemarks! {
if string != "" {
string += "\n"
}
string += mark.qualifiedName
}
self.outputText.text = string
}
} else {
self.resultsLabel.text = "No results"
}
}
}
That gives me a mini-app to test out the data that is returned when I change locations in the Xcode Simulator.
screenshot 2017-07-12 13 54 09
As you can see from this shot, I have centered the map in Jenks, OK (a small town just outside of Tulsa, OK - sort of a 'central US' location.)
When searching for a common place in that area ("Walmart" - which is based in nearby Arkansas, so there are plenty of them around), you can see that only 2 'local' Walmart's come back in the search.
Now, let's move to Bentonville, AR - the home of Walmart......
And, we get two top new results, but the others are the same (and much farther away than Tulsa, OK.....)
We found that if we add the town to the first of the search, the results are much better:
(similar results are true for every search we did - various cities around the US and with other 'common places' like Quiznos (similar results as Walmart when in their home town of Denver, CO...)
As you can see from my code, I tried using the allowedRegion?.northEast and southWest (as I understand it, those should set the search area to about 100 miles around the location, though I'm not sure I set that up right), though no difference was found from this setup (i.e., with/without I get the same results).
The only 'better' results were by putting in the town name along with the 'common' one (though, oddly, different results were returned if the town name was before or after the common one - I didn't check exactly, though I think they are 'best' (i.e., locations are all pretty near) from putting the town name after the common one)
What can I do to get better results without having to tell the user to enter the town name (not a very desirable plan! :)
Thank you in advance for tips - the lookup is a key part of the app (not the test stuff shown in the pictures! ) and users expect to pull up several 'nearby' common places (in this case, we would expect to see all 5 results within something like 20 miles - certainly no more than 100 miles away), so it is an important thing for us that this work much more reliably than we are seeing now.
Why does CLGeocoder reverseGeocodeLocation return a placemark with different lat/long when it looks up address?
Background: In terms of a user "long pressing" on the map to drop a pin, but my code reverse Geocoding this to be able to put an area name on the Pin, but then the PIN dropped is in a different location (i.e. not a good user experience). So I'm looking for a way to utilise the lat/long the user actually selected, but then just look up the location name.
Example: With code below I see:
Input: -28.7780218895614, 152.978574011267
OUTPUT: -28.864405, 153.0001191
Code:
import UIKit
import CoreLocation
import PlaygroundSupport
// Initial Test Co-ordinate
let locInput = CLLocation(latitude: -28.778021889561444, longitude: 152.97857401126666)
print("Input: \(locInput.coordinate.latitude), \(locInput.coordinate.longitude)")
// Initiate Reverse Geocoding
let geocoder: CLGeocoder = CLGeocoder()
print("About to call reverse geocoding function")
geocoder.reverseGeocodeLocation(locInput) { placemarks, error in
guard let placemarks = placemarks else {fatalError("No Placemarks Provided \(error?.localizedDescription)")}
for p in placemarks {
print("OUTPUT: \(p.location!.coordinate.latitude), \(p.location!.coordinate.longitude)")
}
}
// Enable Asynch
PlaygroundPage.current.needsIndefiniteExecution = true
It's a correct behaviour. The placemark will returns it's associated location. Which obviously could differ from the input one. When you provide a location to the geocoder, this one will "infer" the placemark you want to get.
Suppose this:
a: Associated location with the empire state building.
b: Location you provided from an long press for instance.
-------
| |
| a | --> CLPlacemark: Empire state building, location: a
| b|
-------
You were right in your assumptions. :)
I am trying to convert the location address to coordinates and open it inside the maps app, but I am getting this error when the function is called.
[Client] Geocode error: <private>. That is the only thing printed inside the console.
#IBAction func openinmaps(_ sender: AnyObject) {
var geocoder: CLGeocoder = CLGeocoder()
var location = "1 Infinite Loop"
geocoder.geocodeAddressString(location,completionHandler: {(placemarks: [CLPlacemark]?, error: NSError?) -> Void in
if (placemarks?.count > 0) {
var topResult: CLPlacemark = (placemarks?[0])!
var placemark: MKPlacemark = MKPlacemark(placemark: topResult)
let regionDistance:CLLocationDistance = 10000
let coordinates = CLLocationCoordinate2DMake(placemark.coordinate.latitude, placemark.coordinate.latitude)
let regionSpan = MKCoordinateRegionMakeWithDistance(coordinates, regionDistance, regionDistance)
let options = [
MKLaunchOptionsMapCenterKey: NSValue(mkCoordinate: regionSpan.center),
MKLaunchOptionsMapSpanKey: NSValue(mkCoordinateSpan: regionSpan.span)
]
let mapItem = MKMapItem(placemark: placemark)
mapItem.openInMaps(launchOptions: options)
}
})
}
My extension for CLLocationManagerDelegate was randomly crashing because of the same error: [Client] Geocode error: <private> in swift 3.0.
The thing is:
geocoder.reverseGeocodeLocation(startLocation, completionHandler: {
placemarks, error in
})
placemarks sometimes was returning nil...
So... I realised that I was playing with my HTTP proxy in order to test some request to the Google API from my device with the Charles Proxy. Removing the Manual HTTP proxy address on my iPhone did the trick and geocoder was working fine again.
I hope it helps.
PD: Nevermind...after 30 seconds or even less, app crashes with the same debug message: [Client] Geocode error:
I had the same issue, it seems there is a limit when geocoding by address and this is the error for this.
My workaround was to put sleep(1) after each geocode in my loop, find the location latitude and longitude and post them back into my database against each venue I was plotting.
This means it now doesn't need to use the geocoder to plot the annotations on the map as it just uses the lat and long to do so. This will work for fixed sets of data but for stuff on the fly you would need another way. Apparently sleep(2) will enable you to plot continuously through large volumes of data but ends up taking a while for everything to plot.
I've added a default lat and long of 0.0 into my database and upon launching the app it will scan through to find any new venues and will then geocode these and post the lat and long back. I had to do a couple of runs through originally to get ~700 venues lats and longs but I've had no trouble since.
I am making a single view application in Xcode, with Google Map SDK. I have followed instructions online and my application can successfully load the google map view. I have also enabled myLocation, so that myLocation button shows on the map view.
I understand that clicking the myLocation button will change the camera location automatically, but I'm wondering what I should do to use the data of myLocation (say to add a marker or add a path node)?
I've tried directly accessing mapView.myLocation, for example
let lat = mapView.myLocation?.coordinate.latitude
let long = mapView.myLocation?.coordinate.longitude
path.addCoordinate(CLLocationCoordinate2D(latitude: lat!, longitude: long!))
However, this will crash the applicaton and throw:
fatal error: unexpectedly found nil while unwrapping an Optional value
What does this error message mean and how should I resolve this?
The error says that myLocation property of mapView is nil. You should check if there is a value before accessing it.
if let myLocation = mapView.myLocation {
let lat = myLocation.coordinate.latitude
let long = myLocation.coordinate.longitude
path.addCoordinate(CLLocationCoordinate2D(latitude: lat, longitude: long))
}
Also verify why myLocation is nil. It might be that the user didn't allow location services.
This will not give any errors:
let lat = mapView.myLocation?.coordinate.latitude ?? give any value of latitude
let long = mapView.myLocation?.coordinate.longitude ?? give any value of longitude
I am working on an app for iOS 7 and I need to find the location of the user and then check to see what other users are also at that same location. I need it to update as soon as the user opens the app as well as update every so often and will display the users at the same location. I have looked at the available examples, but there doesn't seem to be enough on this using Parse. Can anyone give me any help on how to go about doing this, or if anyone knows of some examples similar to what I'm trying to do I would greatly appreciate it. Thanks in advance!
You need to break your problem down and tackle the various pieces -
Obtain the user's location when the app opens and periodically
The Location and Maps programming guide is a good starting point. You can use CLLocationManager to obtain your initial location and you can register for the significant location change event to get updates periodically, even when your app isn't running. Apple has example code plus there are plenty of other examples out there - Just search using "Core Location examples"
Store the user's location in your Parse database
There are examples and documentation on Parse.com showing how to do this. You can also provide a web service that allows your app to query the database for other users at the same location
Identify other users at the same location when your app isn't running
You can use Parse background jobs to trawl your database, match user locations and send push notifications to your users. Again there are examples on Parse.com showing how to set up background jobs and push notifications
this may help this will get your current location then save to parse, its just a matter of querying parse to pull the data down
func locationManager(manager: CLLocationManager!, didUpdateLocations
locations: [AnyObject]!) {
var userLocation : CLLocation = locations[0] as! CLLocation
var latitude = userLocation.coordinate.latitude
var longitude = userLocation.coordinate.longitude
var latDelta : CLLocationDegrees = 0.01
var lonDelta : CLLocationDegrees = 0.01
var span : MKCoordinateSpan = MKCoordinateSpanMake(latDelta,
lonDelta)
var location : CLLocationCoordinate2D = CLLocationCoordinate2DMake(latitude, longitude)
var region : MKCoordinateRegion = MKCoordinateRegionMake(location, span)
self.mapView.setRegion(region, animated: true)
let testObject = PFObject(className: "User")
let currentPoints = PFGeoPoint(latitude: latitude, longitude: longitude)
testObject.setValue(currentPoints, forKey: "currentLocation")
testObject.saveInBackgroundWithBlock { (success: Bool, error: NSError?) -> Void in
if (success) {
dispatch_async(dispatch_get_main_queue()) {
println("added to parse")
}
} else {
println(error)
}
}
}