Swift 3 - Mapbox - 自定义用户位置注释

我正在寻找更改用户位置注释的外观.我知道现在可以使用MGLUserLocationAnnotationView,但是,我不确定如何实现它.任何人都可以提供一个如何做到这一点的简单例子吗？

谢谢

1> dzensik..：

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你是对的.MapBox API MGLUserLocationAnnotationView描述非常简短.自MapBox iOS SDK 3.4.0起,用户位置视图自定义可用.另请参阅MapBox GitHub上的功能注释

需要注意的是:MGLUserLocationAnnotationView是MGLAnnotationView的子类.这意味着MGLUserLocationAnnotationView的行为就像普通的注释视图一样.

以下是如何自定义用户位置视图的示例.创建一个新类(例如CustomUserLocationAnnotationView)并覆盖layoutSubviews()以添加自定义代码.在这个例子中,我使用UIImage UserLocationIcon.png来可视化地图上的用户位置.

import Foundation
import UIKit
import Mapbox

final class CustomUserLocationAnnotationView: MGLUserLocationAnnotationView {
    override init(reuseIdentifier: String?) {
        super.init(reuseIdentifier: reuseIdentifier)
    }

    override init(frame: CGRect) {
        super.init(frame: CGRect(x: 0, y: 0, width: 30, height: 30))
    }

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

    override func layoutSubviews() {
        super.layoutSubviews()

        // Force the annotation view to maintain a constant size when the map is tilted.
        scalesWithViewingDistance = false

        layer.contentsScale = UIScreen.main.scale
        layer.contentsGravity = kCAGravityCenter

        // Use your image here
        layer.contents = UIImage(named: "UserLocationIcon")?.cgImage
    }
}

在你的UIViewController或其他任何东西(例如Service类)中,使用至少两个函数-mapViewDidFinishLoadingMap:和-mapView:viewForAnnotation:实现MGLMapViewDelegate.查看我的评论内联:

extension ViewController: MGLMapViewDelegate {
    // Wait until the map is loaded before proceed with other actions on map
    func mapViewDidFinishLoadingMap(_ mapView: MGLMapView) {
        // Show the user location here
        mapView.showsUserLocation = true
    }

    func mapView(_ mapView: MGLMapView, viewFor annotation: MGLAnnotation) -> MGLAnnotationView? {
        // Customise the user location annotation view
        if annotation is MGLUserLocation {
            var userLocationAnnotationView = mapView.dequeueReusableAnnotationView(withIdentifier: "CustomUserLocationAnnotationViewIdentifier") as? CustomUserLocationAnnotationView

            if userLocationAnnotationView == nil {
                userLocationAnnotationView = CustomUserLocationAnnotationView(reuseIdentifier: "CustomUserLocationAnnotationViewIdentifier")
            }

            // Optional: You can save the annotation object for later use in your app
            self.userLocationAnnotation = annotation

            return userLocationAnnotationView
        }

        // Customise your annotation view here...

        return customAnnotationView
    }
}

为每个注释视图实例(包括用户注释视图)调用MapView -mapView:viewForAnnotation:delegate函数.

可选:要获取CustomUserLocationAnnotationView实例,可以在代码中的任何位置使用此函数:

    // The userLocationAnnotation was previously saved in your ViewController in the -mapView:viewForAnnotation: delegate function
    let view = mapView.view(for: self.userLocationAnnotation) as? CustomUserLocationAnnotationView

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@huggie我也有同样的问题,`viewForAnnotation`没有被调用.我发现这是因为我在故事板中设置了`mapView`,然后我将`ShowUserLocation`设置为`On`.将其设置为"Default"后,我的`viewForAnnotation`被调用.在代码中使用`mapView.showsUserLocation`可以正常工作.