在MapView上检测缩放更改

let mapView = MKMapView()

// 设置地图视图的初始范围
mapView.setRegion(MKCoordinateRegion(center: CLLocationCoordinate2D(latitude: 39.916528, longitude: -104.885737), span: MKCoordinateSpan(latitudeDelta: 0.05, longitudeDelta: 0.05)))

// 设置地图视图的投影
mapView.projection = MKMapViewProjection(from: MKMapPoint(x: 0.0, y: 0.0) to: MKMapPoint(x: 1.0, y: 1.0))

// 设置投影视图
mapView.projectionView = MKMapView(frame: CGRect(x: 0, y: 0, width: 100, height: 100))

let mapView = MKMapView()

// 设置地图视图的初始范围
mapView.setRegion(MKCoordinateRegion(center: CLLocationCoordinate2D(latitude: 39.916528, longitude: -104.885737), span: MKCoordinateSpan(latitudeDelta: 0.05, longitudeDelta: 0.05)))

// 创建一个上下文
let context = CGContext(data: nil, width: 1, height: 1)

// 将地图视图绘制到上下文中
context.setFillColor(red: 0, green: 0, blue: 0, alpha: 0)
context.fill(CGRect(x: 0, y: 0, width: 100, height: 100))

// 将上下文数据传递给地图视图
mapView.draw(in: CGRect(x: 0, y: 0, width: 100, height: 100))