这是我的代码......
-(void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
{
location_updated = [locations lastObject];
NSLog(@"updated coordinate are %@",location_updated);
latitude1 = location_updated.coordinate.latitude;
longitude1 = location_updated.coordinate.longitude;
self.lblLat.text = [NSString stringWithFormat:@"%f",latitude1];
self.lblLon.text = [NSString stringWithFormat:@"%f",longitude1];
NSString *str = [NSString stringWithFormat:@"https://maps.googleapis.com/maps/api/geocode/json?latlng=%f,%f&sensor=false",latitude1,longitude1];
url = [NSURL URLWithString:str];
NSURLRequest *request = [NSURLRequest requestWithURL:url];
connection = [NSURLConnection connectionWithRequest:request delegate:self];
if (connection)
{
webData1 = [[NSMutableData alloc]init];
}
GMSMarker *marker = [[GMSMarker alloc] init];
marker.position = CLLocationCoordinate2DMake(latitude1,longitude1);
marker.title = formattedAddress;
marker.icon = [UIImage imageNamed:@"m2.png"];
marker.map = mapView_;
marker.draggable = YES;
}
这个方法多次调用,我不想......
在那里添加一些限制。对于位置和准确度之间的时间跨度
-(void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
{
CLLocation *newLocation = locations.lastObject;
NSTimeInterval locationAge = -[newLocation.timestamp timeIntervalSinceNow];
if (locationAge > 5.0) return;
if (newLocation.horizontalAccuracy < 0) return;
// Needed to filter cached and too old locations
//NSLog(@"Location updated to = %@", newLocation);
CLLocation *loc1 = [[CLLocation alloc] initWithLatitude:_currentLocation.coordinate.latitude longitude:_currentLocation.coordinate.longitude];
CLLocation *loc2 = [[CLLocation alloc] initWithLatitude:newLocation.coordinate.latitude longitude:newLocation.coordinate.longitude];
double distance = [loc1 distanceFromLocation:loc2];
if(distance > 20)
{
_currentLocation = newLocation;
//significant location update
}
//location updated
}
你可以写:[经理stopUpdatingLocation];经理=零;在didupdatelocation委托中
在分配LocationManager
对象时,您可以设置distanceFilter
的LocationManager
属性。距离过滤器属性是CLLocationDistance
值,可以设置为通知位置管理器有关以米为单位移动的距离。您可以按如下方式设置距离过滤器:
LocationManager *locationManger = [[CLLocationManager alloc] init];
locationManager.delegate = self;
locationManager.distanceFilter = 100.0; // Will notify the LocationManager every 100 meters
locationManager.desiredAccuracy = kCLLocationAccuracyBest;
最简单的方法:
-(void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray<CLLocation *> *)locations
{
[manager stopUpdatingLocation];
manager.delegate = nil;
//...... do something
}
如果没有委托引用,管理器找不到你的didUpdateLocations方法:-D
但是在使用startUpdatingLocation之前不要忘记再次设置它
我有类似的情况。你可以使用dispatch_once:
static dispatch_once_t predicate;
- (void)update
{
if ([CLLocationManager authorizationStatus] == kCLAuthorizationStatusNotDetermined &&
[_locationManager respondsToSelector:@selector(requestWhenInUseAuthorization)]) {
[_locationManager requestWhenInUseAuthorization];
}
_locationManager.delegate = self;
_locationManager.distanceFilter = kCLDistanceFilterNone;
_locationManager.desiredAccuracy = kCLLocationAccuracyBest;
predicate = 0;
[_locationManager startUpdatingLocation];
}
- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations {
[manager stopUpdatingLocation];
manager = nil;
dispatch_once(&predicate, ^{
//your code here
});
}
您可以使用静态变量来存储最新的位置时间戳,然后将其与最新的位置时间戳进行比较,如下所示:
- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
{
[manager stopUpdatingLocation];
static NSDate *previousLocationTimestamp;
CLLocation *location = [locations lastObject];
if (previousLocationTimestamp && [location.timestamp timeIntervalSinceDate:previousLocationTimestamp] < 2.0) {
NSLog(@"didUpdateLocations GIVE UP");
return;
}
previousLocationTimestamp = location.timestamp;
NSLog(@"didUpdateLocations GOOD");
// Do your code here
}
如果要停止更新位置管理器,请编写此方法
[locationManager stopUpdatingLocation];
对于时间限制,我不理解接受的答案中的代码,发布不同的方法。正如Rob指出的那样“当你第一次启动位置服务时,你可能会多次看到它被调用”。下面的代码作用于第一个位置,并在前120秒忽略更新的位置。它是解决原始问题“如何停止多次调用didUpdateLocations的方法”的一种方法。
在.h文件中:
@property(strong,nonatomic) CLLocation* firstLocation;
在.m文件中:
// is this the first location?
CLLocation* newLocation = locations.lastObject;
if (self.firstLocation) {
// app already has a location
NSTimeInterval locationAge = [newLocation.timestamp timeIntervalSinceDate:self.firstLocation.timestamp];
NSLog(@"locationAge: %f",locationAge);
if (locationAge < 120.0) { // 120 is in seconds or milliseconds?
return;
}
} else {
self.firstLocation = newLocation;
}
// do something with location
你可以设置一个标志(Bool)。当您实例化您的locationsManager set flag = true时,当locationManager:didUpdateLocations在您想要仅运行一次的代码块内返回set flag = false时。这样它只会运行一次。
if flag == true {
flag = false
...some code probably network call you only want to run the once
}
位置管理器将被多次调用,但是您只想执行一次代码,我认为这是您要实现的目标?
locationManager.startUpdatingLocation()连续获取位置并且didUpdateLocations方法调用多次,只需在调用locationManager.startUpdatingLocation()之前设置locationManager.distanceFilter值的值。
因为我设置200米(你可以根据你的要求改变)工作正常
locationManager = CLLocationManager()
locationManager.delegate = self
locationManager.desiredAccuracy = kCLLocationAccuracyBest
locationManager.distanceFilter = 200
locationManager.requestWhenInUseAuthorization()
locationManager.startUpdatingLocation()