Mac Catalyst应用中Map View的Annotation View弹出框内容被截断求助

方法1：自定义Callout View（推荐） #

系统默认Callout在Mac Catalyst环境下存在布局适配问题，直接自定义Callout内容视图可以完全控制文本显示：

class CustomCalloutView: UIView {
    private let addressLabel: UILabel = {
        let label = UILabel()
        label.numberOfLines = 0
        label.lineBreakMode = .byWordWrapping
        label.translatesAutoresizingMaskIntoConstraints = false
        return label
    }()
    
    init(address: String) {
        super.init(frame: .zero)
        addSubview(addressLabel)
        addressLabel.text = address
        
        NSLayoutConstraint.activate([
            addressLabel.leadingAnchor.constraint(equalTo: leadingAnchor, constant: 8),
            addressLabel.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -8),
            addressLabel.topAnchor.constraint(equalTo: topAnchor, constant: 8),
            addressLabel.bottomAnchor.constraint(equalTo: bottomAnchor, constant: -8)
        ])
        
        // 模拟系统Callout样式
        backgroundColor = .white
        layer.cornerRadius = 8
        layer.borderColor = UIColor.lightGray.cgColor
        layer.borderWidth = 1
    }
    
    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
}

// 在MapView的代理方法中配置标注视图
func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
    guard let customAnnotation = annotation as? YourAnnotationModel else { return nil }
    
    let reuseID = "LocationPin"
    var pinView = mapView.dequeueReusableAnnotationView(withIdentifier: reuseID) as? MKPinAnnotationView
    
    if pinView == nil {
        pinView = MKPinAnnotationView(annotation: customAnnotation, reuseIdentifier: reuseID)
        pinView?.canShowCallout = true
        // 替换系统默认详情视图为自定义视图
        pinView?.detailCalloutAccessoryView = CustomCalloutView(address: customAnnotation.address)
        pinView?.calloutOffset = CGPoint(x: -5, y: 5)
    } else {
        pinView?.annotation = customAnnotation
        // 更新自定义视图的文本内容
        if let calloutView = pinView?.detailCalloutAccessoryView as? CustomCalloutView {
            calloutView.addressLabel.text = customAnnotation.address
        }
    }
    
    return pinView
}

方法2：调整系统Callout的文本约束（临时方案） #

通过遍历系统Callout的子视图，修改详情Label的布局属性，注意该方法可能随系统版本更新失效：

func mapView(_ mapView: MKMapView, didSelect view: MKAnnotationView) {
    // 延迟执行确保Callout已完成加载
    DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
        view.calloutView?.subviews.forEach { subview in
            guard let label = subview as? UILabel,
                  let address = (view.annotation as? YourAnnotationModel)?.address,
                  label.text == address else { return }
            
            label.numberOfLines = 0
            label.preferredMaxLayoutWidth = 250 // 设置最大换行宽度
            label.sizeToFit()
        }
    }
}

方法3：清理文本内容 #

检查地址文本是否包含多余换行或特殊字符，统一处理后再赋值：

// 清理地址文本
let cleanedAddress = customAnnotation.address
    .replacingOccurrences(of: "\n", with: " ")
    .trimmingCharacters(in: .whitespacesAndNewlines)

内容的提问来源于stack exchange，提问作者Manish