我有一个 MKMapView，我想在长按手势上添加注释。添加注释后，我想选择注释 View 。我认为这是一个非常简单的请求。

问题是我正在使用带有自定义 rightCalloutAccessoryView 和自定义 detailCalloutAccessoryView 的新 MKMarkerAnnotationView。目前还没有很好的记录，但是 WWDC 2017 Session 237声明当有多个标题/副标题时将显示标注。

不幸的是，我不是这种情况。当我以编程方式(和手动)选择注释时，我得到一个奇怪的双选状态，我可以在其中看到标注和标记:

下面是注释 View 代码:

import Foundation
import MapKit

@available(iOS 11.0, *)
protocol TemporaryUserAnnotationViewDelegate: class {
    func temporaryUserAnnotationViewDidTapOk(title: String?, userAnnotationView: TemporaryUserAnnotationView)
}

@available(iOS 11.0, *)
class TemporaryUserAnnotationView: MKMarkerAnnotationView {

    weak var delegate: TemporaryUserAnnotationViewDelegate?
    var textField: UITextField!

    init(annotation: TemporaryUserAnnotation) {
        super.init(annotation: annotation, reuseIdentifier: TemporaryUserAnnotationMarkerAnnotationView.reuseIdentifier)
        markerTintColor = .lbc_blue
        canShowCallout = true
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    func configure(annotation: TemporaryUserAnnotation) {
        let detailView = UIView()
        detailView.translatesAutoresizingMaskIntoConstraints = false
        textField = UITextField()
        textField.translatesAutoresizingMaskIntoConstraints = false
        textField.placeholder = "Titre"
        detailView.addSubview(textField)
        detailView.heightAnchor.constraint(equalToConstant: 21).isActive = true
        detailView.widthAnchor.constraint(equalToConstant: 100).isActive = true
        textField.centerXAnchor.constraint(equalTo: detailView.centerXAnchor).isActive = true
        textField.centerYAnchor.constraint(equalTo: detailView.centerYAnchor).isActive = true
        textField.heightAnchor.constraint(equalToConstant: 21).isActive = true
        textField.widthAnchor.constraint(equalToConstant: 100).isActive = true
        detailCalloutAccessoryView = detailView

        let rightView = UIView(frame: CGRect(origin: .zero, size: CGSize(width: 50, height: 70)))
        rightView.backgroundColor = .lbc_blue
        let button = UIButton(frame: CGRect(origin: .zero, size: CGSize(width: 50, height: 40)))
        button.setTitle("OK", for: .normal)
        button.setTitleColor(.white, for: .normal)
        button.addTarget(self, action: #selector(tapRightCalloutAccessoryViewButton), for: .touchUpInside)
        rightView.addSubview(button)
        rightCalloutAccessoryView = rightView
    }

    @objc func tapRightCalloutAccessoryViewButton() {
        delegate?.temporaryUserAnnotationViewDidTapOk(title: textField.text, userAnnotationView: self)
    }
}

这是 Controller 代码:

func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
    print(#function)
    if annotation is MKUserLocation { return nil }
    if #available(iOS 11.0, *) {
        switch annotation {
        case let temporarayUserAnnotation as TemporaryUserAnnotation:
            if let view = mapView.dequeue() as? TemporaryUserAnnotationView {
                view.annotation = annotation
                return view
            } else {
                let view = TemporaryUserAnnotationView(annotation: temporarayUserAnnotation)
                view.delegate = self
                view.configure(annotation: temporarayUserAnnotation)
                return view
            }
        default:
            return nil
        }
    } else {
        let identifier = "marker"
        if let view = mapView.dequeueReusableAnnotationView(withIdentifier: identifier) as? MKPinAnnotationView {
            view.annotation = annotation
            return view
        } else {
            return MKPinAnnotationView(annotation: annotation, reuseIdentifier: identifier)
        }
    }
}

我只是这样添加注释:

func addUserAnnotation(coordinate: CLLocationCoordinate2D) {
    let annotation = TemporaryUserAnnotation(coordinate: coordinate)
    mapView.addAnnotation(annotation)
    mapView.selectAnnotation(annotation, animated: true)
}

我还尝试实现 mapView(_:didAdd:) 方法，但结果在标注前面的标记 View 更糟。

任何帮助将不胜感激!谢谢!

最佳答案

我发现了以下解决方法:添加注释时，请稍等片刻，然后再以编程方式选择它:

func addUserAnnotation(coordinate: CLLocationCoordinate2D) {
    let annotation = TemporaryUserAnnotation(coordinate: coordinate)
    mapView.addAnnotation(annotation)
    DispatchQueue.main.asyncAfter(wallDeadline: .now() + .seconds(1)) {
        self.mapView.selectAnnotation(annotation, animated: true)
    }
}

我仍然认为这应该不是必需的，所以如果您有更好的解决方案，请随时在这里发布!

关于swift - 添加注释后选择带有自定义标注的 MKMarkerAnnotationView，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/46674767/