我的所有代码都在AppDelegate.m文件中：
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
self.window = [[UIWindow alloc]initWithFrame:[[UIScreen mainScreen]bounds]];
_locationMgr = [[CLLocationManager alloc] init];
[_locationMgr setDelegate:self];
if([_locationMgr respondsToSelector:@selector(setAllowsBackgroundLocationUpdates:)])
[_locationMgr setAllowsBackgroundLocationUpdates:YES];
CLAuthorizationStatus authorizationStatus= [CLLocationManager authorizationStatus];
if([launchOptions valueForKey:UIApplicationLaunchOptionsLocationKey] != nil) {
NSLog(@"relaunching because of significant location change - restarting SLC");
[_locationMgr startMonitoringSignificantLocationChanges];
}
else
{
if (authorizationStatus == kCLAuthorizationStatusAuthorizedAlways) {
NSLog(@"launching with authorization to always use location - starting SLC");
[_locationMgr startMonitoringSignificantLocationChanges];
}
else
{
NSLog(@"launching with no authorization to always use location - requesting authorization");
if([_locationMgr respondsToSelector:@selector(requestAlwaysAuthorization)])
[_locationMgr requestAlwaysAuthorization];
}
}
if([userdefaults objectForKey:@"pfuser"] == nil) {
NSLog(@"in delegate signup");
SignUpController *signup = [[SignUpController alloc] init];
[self.window setRootViewController:signup];
}
else {
ViewController *map = [[ViewController alloc] init];
[self.window setRootViewController:map];
}
[self.window makeKeyAndVisible];
return YES;
}
- (void)startSignificantChangeUpdates
{
deviceNotFoundAlertController = [UIAlertController alertControllerWithTitle:@"START" message:@"startSignificantChangeUpdates called" preferredStyle:UIAlertControllerStyleAlert];
[deviceNotFoundAlertController addAction:deviceNotFoundAlert];
// Create the location manager if this object does not
// already have one.
if (nil == _locationMgr) {
_locationMgr = [[CLLocationManager alloc] init];
_locationMgr.delegate = self;
}
[CLLocationManager significantLocationChangeMonitoringAvailable];
[_locationMgr startMonitoringSignificantLocationChanges];
}
-(void)locationManger:(CLLocationManager *)manager didFailWithError:(NSError *)error {
NSLog(@"didFailWithError: %@", error);
deviceNotFoundAlertController = [UIAlertController alertControllerWithTitle:@"LOCATION FAIL" message:@"didFailWithError" preferredStyle:UIAlertControllerStyleAlert];
[deviceNotFoundAlertController addAction:deviceNotFoundAlert];
}
// Delegate method from the CLLocationManagerDelegate protocol.
- (void)_locationManager:(CLLocationManager *)manager
didUpdateLocations:(NSArray *)locations {
deviceNotFoundAlertController = [UIAlertController alertControllerWithTitle:@"LOCATION UPDATE" message:@"didUpdateLocations called" preferredStyle:UIAlertControllerStyleAlert];
[deviceNotFoundAlertController addAction:deviceNotFoundAlert];
// 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 (fabs(howRecent) < 15.0) {
// If the event is recent, do something with it.
NSLog(@"latitude %+.6f, longitude %+.6f\n",
location.coordinate.latitude,
location.coordinate.longitude);
}
}
似乎没有任何警报发生，看起来委托方法并未被调用。
更新
现在我有：
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
self.window = [[UIWindow alloc]initWithFrame:[[UIScreen mainScreen]bounds]];
deviceNotFoundAlert = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:nil];
...
}
// Delegate method from the CLLocationManagerDelegate protocol.
- (void)locationManager:(CLLocationManager *)manager
didUpdateLocations:(NSArray *)locations {
deviceNotFoundAlertController = [UIAlertController alertControllerWithTitle:@"LOCATION UPDATE" message:@"didUpdateLocations called" preferredStyle:UIAlertControllerStyleAlert];
[deviceNotFoundAlertController addAction:deviceNotFoundAlert];
// 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 (fabs(howRecent) < 15.0) {
// If the event is recent, do something with it.
NSLog(@"latitude %+.6f, longitude %+.6f\n",
location.coordinate.latitude,
location.coordinate.longitude);
}
}
当我测试这个应用时，我会在家里打开它，然后关闭它，这样当我离开家时，它应该在某个时候发送一个警报（或3个），但是我没有从任何委托方法中收到警报（我在那里放置了警报）。
我有一个想法，也许我必须从主
UIViewController而不是AppDelegate显示警报？这可能是我没有看到警报的原因：如何在应用程序委托中添加UIAlertController (obj-c) 更新：
这是我现在处理警报的方式：
deviceNotFoundAlertController = [UIAlertController alertControllerWithTitle:@"START" message:@"startSignificantChangeUpdates called" preferredStyle:UIAlertControllerStyleAlert];
[deviceNotFoundAlertController addAction:deviceNotFoundAlert];
alertWindow = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
alertWindow.rootViewController = [[UIViewController alloc] init];
alertWindow.windowLevel = UIWindowLevelAlert + 1;
[alertWindow makeKeyAndVisible];
[alertWindow.rootViewController presentViewController:deviceNotFoundAlertController animated:YES completion:nil];
更新
警报似乎不是问题所在，在startSignificantChangeUpdates的警报从未出现。当我距离初始位置500米时，它是否应该出现？
更新
有人能帮我理解一下吗？
您的代理对象的方法从启动相应位置服务的线程中调用。该线程本身必须具有活动运行循环，就像您的应用程序主线程中找到的那个运行循环一样。
更新
我想我已经理解了上面的引用所说的内容...而且我现在有这个 - 我明天会测试。
...
if([launchOptions valueForKey:UIApplicationLaunchOptionsLocationKey] != nil) {
NSLog(@"relaunching because of significant location change - restarting SLC");
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
[_locationMgr startMonitoringSignificantLocationChanges];
});
}
else
{
if (authorizationStatus == kCLAuthorizationStatusAuthorizedAlways) {
NSLog(@"launching with authorization to always use location - starting SLC");
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
[_locationMgr startMonitoringSignificantLocationChanges];
});
}
else
{
NSLog(@"launching with no authorization to always use location - requesting authorization");
if([_locationMgr respondsToSelector:@selector(requestAlwaysAuthorization)])
[_locationMgr requestAlwaysAuthorization];
}
}
...
我认为代码正在自己的线程上启动位置服务。我已经注意到一件事，在退出应用程序时，右上角的位置会消失。我刚刚升级到iOS 10。在iOS 9中，右上角的位置箭头会保留，但当应用程序未运行时它只会成为黑色轮廓。这可能是他们在iOS 10中更改的内容，或者现在因为我升级到10，其他东西现在不起作用了。或者这就是当位置服务在它们自己的线程上运行时发生的情况。从这里开始：iOS start Background Thread 更新
也许我没有正确地使用线程，但正如我所说，现在当我关闭应用程序时，位置服务会停止。当我没有使用线程时，位置服务箭头仍将保留在右上方，作为一个轮廓。
更新
我读到服务应该在主线程上启动 - 所以现在我有了：
CLAuthorizationStatus authorizationStatus= [CLLocationManager authorizationStatus];
NSLog(@"launching with no authorization to always use location - requesting authorization");
if([_locationMgr respondsToSelector:@selector(requestAlwaysAuthorization)]) {
[_locationMgr requestAlwaysAuthorization];
}
if([launchOptions valueForKey:UIApplicationLaunchOptionsLocationKey] != nil) {
NSLog(@"relaunching because of significant location change - restarting SLC");
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
[_locationMgr startMonitoringSignificantLocationChanges];
});
}
else if (authorizationStatus == kCLAuthorizationStatusAuthorizedAlways) {
NSLog(@"launching with authorization to always use location - starting SLC");
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
[_locationMgr startMonitoringSignificantLocationChanges];
});
}
else {
//
}
当应用程序关闭时，右侧的箭头不会显示出来，这是iOS 10中的新功能吗，不再显示它了吗？
更新
我不小心删除了：_locationMgr = [[CLLocationManager alloc] init]; 我现在加上它，现在箭头总是在那里，今天要进行测试。
更新
我测试了一下，仍然没有提示。
所需的背景模式和应用程序注册位置更新，其中包含Item0。 - ewizard