iphone - 不断检查 ios 中启用的位置服务

Question

我正在尝试制作一个应用程序，其中视图将检查位置服务是否已启用。如果未启用，则会弹出提示，但仍会继续搜索位置但不提示。一旦启用位置服务，它将继续其过程。

怎么做？？？

Answer 1

如果位置服务被禁用，您将无法继续获取位置。

如果您想继续搜索位置，请确保通过检查启用该服务

[CLLocationManager locationServicesEnabled]

如果启用，开始更新位置

[locationManager startUpdatingLocation];

然后在

- (void)locationManager:(CLLocationManager *)manager
    didUpdateToLocation:(CLLocation *)newLocation
           fromLocation:(CLLocation *)oldLocation {
    [locationManager stopUpdatingLocation]; // This will stop to check the location
}

删除此代码以仍然检查位置[locationManager stopUpdatingLocation];，但这不是最好的方法，请务必阅读apple documentation for the policy of getting the location

Answer 2

添加 .h 文件 int 计数器；

在你的视图的 viewDidLoad 方法中添加这个，因为它会检查你可以增加计数器的每一秒：

[NSTimer scheduledTimerWithTimeInterval:1.0     
                             target:self
                           selector:@selector(checkLocationMangerEnabled:)     
                           userInfo:nil     
                            repeats:YES];

 counter = 0;

现在选择器将是：

-(void)checkLocationMangerEnabled:(id)sender
{
   if([CLLocationManager locationServicesEnabled])
   {
      //here location is enabled
   }
   else
   { //Not enabled
     if(counter == 60) // alert will showed in every 1 min u can increase or decrese
     {
       UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Location Service Disabled" 
                                                    message:@"To re-enable, please go to Settings and turn on Location Service for this app." 
                                                   delegate:nil 
                                          cancelButtonTitle:@"OK" 
                                          otherButtonTitles:nil];
      [alert show];
      [alert release];
    }
    counter++;
   }
}

Answer 3

您可以通过此代码检查位置服务的可用性：

MKUserLocation *userLocation = map.userLocation;
    BOOL locationAllowed = [CLLocationManager locationServicesEnabled];
    BOOL locationAvailable = userLocation.location!=nil;

    if (locationAllowed==NO) {
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Location Service Disabled" 
                                                        message:@"To re-enable, please go to Settings and turn on Location Service for this app." 
                                                       delegate:nil 
                                              cancelButtonTitle:@"OK" 
                                              otherButtonTitles:nil];
        [alert show];
        [alert release];
    } else {
        if (locationAvailable==NO) 
            [self.map.userLocation addObserver:self forKeyPath:@"location" options:(NSKeyValueObservingOptionNew|NSKeyValueObservingOptionOld) context:nil];
    }