我有一个简单的数组或 MKAnnotations，用于在 View 加载时从 CoreData 获取的位置对象。当我删除一个位置对象时，我也手动从数组中删除了位置对象。从数组中删除后，我调用 removeAnnotations() 然后基于数组调用 addAnnotations()。我注意到 MKAnnotationView 不再位于已删除的位置，但它并未从 MapView 中删除，仅移动到 0º lat 0º lon。
我不确定为了让它从 MapView 中完全删除我做错了什么。
*** 注意:我正在学习教程，对于学习过程，我手动更新位置数组而不是使用 NSFetchedResultsController。
想法？
代码如下:
var managedObjectContext: NSManagedObjectContext! {
didSet {
NSNotificationCenter.defaultCenter().addObserverForName(NSManagedObjectContextObjectsDidChangeNotification, object: managedObjectContext, queue: NSOperationQueue.mainQueue()) { notification in
if self.isViewLoaded() {
if let dictionary = notification.userInfo {
if dictionary["inserted"] != nil {
print("*** Inserted")
let insertedLocationSet: NSSet = dictionary["inserted"] as! NSSet
let insertedLocationArray: NSArray = insertedLocationSet.allObjects
let insertedLocation = insertedLocationArray[0] as! Location
self.locations.append(insertedLocation)
} else if dictionary["deleted"] != nil {
print("*** Deleted")
let deletedLocationSet = dictionary["deleted"] as! NSSet
let deletedLocationArray = deletedLocationSet.allObjects
let deletedLocation = deletedLocationArray[0] as! Location
if let objectIndexInLocations = self.locations.indexOf(deletedLocation) {
self.locations.removeAtIndex(objectIndexInLocations)
}
}
}
}
self.drawAnnotations()
}
}
}
var locations = [Location]()
func updateLocations() { // called by viewDidLoad()
let entity = NSEntityDescription.entityForName("Location", inManagedObjectContext: managedObjectContext)
let fetchRequest = NSFetchRequest()
fetchRequest.entity = entity
locations = try! managedObjectContext.executeFetchRequest(fetchRequest) as! [Location]
drawAnnotations()
}
func drawAnnotations() {
mapView.removeAnnotations(locations)
mapView.addAnnotations(locations)
}
最佳答案
你的问题是，当你执行 mapView.removeAnnotations(locations) 时，locations 数组已经更新，删除的注释不再在该数组中，所以它没有被删除。您可以通过引用 MapView 本身的 annotations 属性来删除所有当前注释 -
func drawAnnotations() {
mapView.removeAnnotations(mapView.annotations)
mapView.addAnnotations(locations)
}
关于ios - MKAnnotationView 未从 MKMapView 中删除，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/34189208/