问题
For my iOS app (building in iOS7),i need to show user's current location when the app load.I am using Google Maps iOS SDK. I am following this
Google Map
But i can't figure it out. Please help if you go through the path.
回答1:
It seems Google Maps iOS SDKcannot access to the device position.
So you have to retrieve the position by using CLLocationManagerof iOS.
First, add the CoreLocation.framework to your project :
- Go in
Project Navigator - Select your project
- Click on the tab
Build Phases - Add the
CoreLocation.frameworkin theLink Binary with Libraries
Then all you need to do is to follow the basic exemple of Apple documentation.
Create a
CLLocationManagerprobably in yourViewDidLoad:if (nil == locationManager) locationManager = [[CLLocationManager alloc] init]; locationManager.delegate = self; //Configure Accuracy depending on your needs, default is kCLLocationAccuracyBest locationManager.desiredAccuracy = kCLLocationAccuracyKilometer; // Set a movement threshold for new events. locationManager.distanceFilter = 500; // meters [locationManager startUpdatingLocation];
With the CLLocationManagerDelegate every time the position is updated, you can update the user position on your Google Maps :
- (void)locationManager:(CLLocationManager *)manager
didUpdateLocations:(NSArray *)locations {
// If it's a relatively recent event, turn off updates to save power.
CLLocation* location = [locations lastObject];
NSDate* eventDate = location.timestamp;
NSTimeInterval howRecent = [eventDate timeIntervalSinceNow];
if (abs(howRecent) < 15.0) {
// Update your marker on your map using location.coordinate.latitude
//and location.coordinate.longitude);
}
}
回答2:
Forget my previous answer. It works well if you use the native MapKit.framework.
In fact GoogleMaps for iOS do all the work for you. You don't have to use CoreLocation directly.
The only thing you have to do is to add yourMapView.myLocationEnabled = YES; and the framework will do everything. (Except center the map on you position).
What I have done : I simply followed the steps of the following documentation. And I got a map centered on Sydney but if I zoomed out and moved to my place (if you use a real device, otherwise use simulator tools to center on Apple's location), I could see the blue point on my position.
Now if you want to update the map to follow your position, you can copy Google example MyLocationViewController.m that is included in the framework directory. They just add a observer on the myLocation property to update the camera properties:
@implementation MyLocationViewController {
GMSMapView *mapView_;
BOOL firstLocationUpdate_;
}
- (void)viewDidLoad {
[super viewDidLoad];
GMSCameraPosition *camera = [GMSCameraPosition cameraWithLatitude:-33.868
longitude:151.2086
zoom:12];
mapView_ = [GMSMapView mapWithFrame:CGRectZero camera:camera];
mapView_.settings.compassButton = YES;
mapView_.settings.myLocationButton = YES;
// Listen to the myLocation property of GMSMapView.
[mapView_ addObserver:self
forKeyPath:@"myLocation"
options:NSKeyValueObservingOptionNew
context:NULL];
self.view = mapView_;
// Ask for My Location data after the map has already been added to the UI.
dispatch_async(dispatch_get_main_queue(), ^{
mapView_.myLocationEnabled = YES;
});
}
- (void)dealloc {
[mapView_ removeObserver:self
forKeyPath:@"myLocation"
context:NULL];
}
#pragma mark - KVO updates
- (void)observeValueForKeyPath:(NSString *)keyPath
ofObject:(id)object
change:(NSDictionary *)change
context:(void *)context {
if (!firstLocationUpdate_) {
// If the first location update has not yet been recieved, then jump to that
// location.
firstLocationUpdate_ = YES;
CLLocation *location = [change objectForKey:NSKeyValueChangeNewKey];
mapView_.camera = [GMSCameraPosition cameraWithTarget:location.coordinate
zoom:14];
}
}
@end
With the doc I gave you and the samples included in the framework you should be able to do what you want.
回答3:
Xcode + Swift + Google Maps iOS
Step by step recipe:
1.) Add key string to Info.plist (open as source code):
<key>NSLocationWhenInUseUsageDescription</key>
<string>This app needs your location to function properly</string>
2.) Add CLLocationManagerDelegate to your view controller class:
class MapViewController: UIViewController, CLLocationManagerDelegate {
...
}
3.) Add CLLocationManager into your class:
var mLocationManager = CLLocationManager()
var mDidFindMyLocation = false
4.) Ask for permission and add observer:
override func viewDidLoad() {
super.viewDidLoad()
mLocationManager.delegate = self
mLocationManager.requestWhenInUseAuthorization()
yourMapView.addObserver(self, forKeyPath: "myLocation", options: NSKeyValueObservingOptions.new, context: nil)
...
}
5.) Wait for authorization and enable location in Google Maps:
func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
if (status == CLAuthorizationStatus.authorizedWhenInUse) {
yourMapView.isMyLocationEnabled = true
}
}
6.) Add observable for change of location:
override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
if (!mDidFindMyLocation) {
let myLocation: CLLocation = change![NSKeyValueChangeKey.newKey] as! CLLocation
// do whatever you want here with the location
yourMapView.camera = GMSCameraPosition.camera(withTarget: myLocation.coordinate, zoom: 10.0)
yourMapView.settings.myLocationButton = true
mDidFindMyLocation = true
print("found location!")
}
}
That's it!
回答4:
On any iOS device, get the user's location with Core Location. Specifically, you want the CLLocation class (and CLLocationManager).
回答5:
Is delegate method didTapMyLocationButton is not way?
https://developers.google.com/maps/documentation/ios/reference/protocol_g_m_s_map_view_delegate-p#ac0e0171b811e839d9021800ca9fd33f4
- (BOOL)didTapMyLocationButtonForMapView:(GMSMapView *)mapView {
return YES;
}
And you can get location by
(lldb) po mapView.myLocation
<+37.33243033,-122.03088128> +/- 386.93m (speed -1.00 mps / course -1.00) @ 5/19/14, 6:22:28 PM Moscow Standard Time
回答6:
The current location won't show on the simulator... connect a real device and give it a try I spent 2 days running in the simulator and don't know that it doesn't simulate locations
回答7:
there are many methods... I used this method and it works in all cases. Google gives you everything with the reponse in json format and its on you how you deal with that data.
Some steps are there to load google map in your project.
find the api key from this link https://developers.google.com/places/ios-api/ sign in with your google account and add your project and create a ios key. then use this in your project
enable all the api needed for google map
a-googlemaps sdk for ios b-googlemap direction api c-" " javasripts api d- picker api e- places api for ios f distance matrix api
in appdelegate method...
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
[GMSServices provideAPIKey:@"xxxxxxxx4rilCeZeUhPORXWNJVpUoxxxxxxxx"];
return YES;
}
- add all needed library and frameworks in your project if google map is not working it means you have to add required framework all the best play with google map
来源：https://stackoverflow.com/questions/20967496/google-maps-ios-sdk-getting-current-location-of-user