我正在Xcode 9 beta,iOS 11中使用Google地图。
我收到如下错误输出到日志:
主线程检查器:在后台线程上调用的UI API:-[UIApplication applicationState] PID:4442,TID:837820,线程名称:com.google.Maps.LabelingBehavior,队列名称:com.apple.root.default-qos.overcommit ,QoS:21
为什么会发生这种情况,因为几乎可以肯定我没有在代码中更改主线程中的任何接口元素。
override func viewDidLoad() {
let locationManager = CLLocationManager()
locationManager.requestAlwaysAuthorization()
locationManager.requestWhenInUseAuthorization()
if CLLocationManager.locationServicesEnabled() {
locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters
locationManager.startUpdatingLocation()
}
viewMap.delegate = self
let camera = GMSCameraPosition.camera(withLatitude: 53.7931183329367, longitude: -1.53649874031544, zoom: 17.0)
viewMap.animate(to: camera)
}
func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
let locValue:CLLocationCoordinate2D = manager.location!.coordinate
print("locations = \(locValue.latitude) \(locValue.longitude)")
}
func mapView(_ mapView: GMSMapView, willMove gesture: Bool) {
}
func mapView(_ mapView: GMSMapView, idleAt position: GMSCameraPosition) {
if(moving > 1){
moving = 1
UIView.animate(withDuration: 0.5, delay: 0, animations: {
self.topBarConstraint.constant = self.topBarConstraint.constant + (self.topBar.bounds.height / 2)
self.bottomHalfConstraint.constant = self.bottomHalfConstraint.constant + (self.topBar.bounds.height / 2)
self.view.layoutIfNeeded()
}, completion: nil)
}
moving = 1
}
// Camera change Position this methods will call every time
func mapView(_ mapView: GMSMapView, didChange position: GMSCameraPosition) {
moving = moving + 1
if(moving == 2){
UIView.animate(withDuration: 0.5, delay: 0, animations: {
self.topBarConstraint.constant = self.topBarConstraint.constant - (self.topBar.bounds.height / 2)
self.bottomHalfConstraint.constant = self.bottomHalfConstraint.constant - (self.topBar.bounds.height / 2)
self.view.layoutIfNeeded()
}, completion: nil)
}
DispatchQueue.main.async {
print("Moving: \(moving) Latitude: \(self.viewMap.camera.target.latitude)")
print("Moving: \(moving) Longitude: \(self.viewMap.camera.target.longitude)")
}
}
mapView(_:didChange)
您将print
语句分派到主队列。您还不在主要队列中吗?如果没有,您也必须将animate
呼叫分派到主队列。我建议您dispatchPrecondition(condition: .onQueue(.main))
在这些UI更新之前插入一些,以确保。