检查 MKMarkerAnnotationView 是否在 MKMapView 中混乱或整理

Question

参考苹果提供的以下示例，我完成了Clustering for Points。 https://developer.apple.com/documentation/mapkit/mkannotationview/decluttering_a_map_with_mapkit_annotation_clustering

我想知道是否有任何方法在注释混乱和整理时被调用。

或

我如何才能知道特定注释是杂乱无章的，因为我需要为此运行一些代码块。

Answer 1

How I can come to know that particular annotation is cluttered and decluttered.

检查 MKClusterAnnotation.memberAnnotations 是否存在 MKAnnotation，如下所示：

func isCluttered(annotation: MKAnnotation) -> Bool {
    let clusters = mapView.annotations.filter({ [=10=] is MKClusterAnnotation }) as! [MKClusterAnnotation]
    for cluster in clusters {
        if cluster.memberAnnotations.first(where: { [=10=] === annotation }) != nil {
            return true
        }
    }
    return false
}

用法： 从 mapView 中随机选取一个注释

let annotations = mapView.annotations.filter { [=11=] is Cycle }
let randomIndex = Int(arc4random_uniform(UInt32(annotations.count)))
if (isCluttered(annotation: annotations[randomIndex])) {
    print("Cluttered")
} else {
    print("Not cluttered")
    mapView.selectAnnotation(annotations[randomIndex], animated: true)
}

check if MKMarkerAnnotationView is cluttered or decluttered in MKMapView

MKMarkerAnnotationView 是 MKAnnotationView 的子类，您可以覆盖 setSelected(_:animated:)，例如从链接的示例代码中打开 ClusterAnnotationView.swift 并粘贴：

override func setSelected(_ selected: Bool, animated: Bool) {
    let cluster = annotation as? MKClusterAnnotation
    print("\(selected ? "Selecting" : "Deselected") Clustered Annotation \(cluster?.memberAnnotations.count ?? -1)")
}

同样，您可以覆盖 CycleAnnotationView.swift 中每个 MKMarkerAnnotationView 中的 setSelected(_:animated:) 方法，粘贴所有 3 类:

override func setSelected(_ selected: Bool, animated: Bool) {
    print("\(selected ? "Selecting" : "Deselected") unclustered annotation with type: \(clusteringIdentifier!)")
}

现在运行并点击地图上的注释并检查打印消息的调试区域。

检查 MKMarkerAnnotationView 是否在 MKMapView 中混乱或整理

check if MKMarkerAnnotationView is cluttered or decluttered in MKMapView

mkmapview

swift