如何在Mapbox iOS SDK中为FillLayer多边形添加交互？

不用自己添加UITapGestureRecognizer，Mapbox iOS SDK提供了更精准的图层要素交互处理方案，步骤如下：

1. 启用FillLayer的交互属性 #

创建FillLayer时，必须开启isInteractive，这样SDK才会监听该图层内要素的点击事件：

// 加载本地GeoJSON数据源
let geoJSONURL = Bundle.main.url(forResource: "你的GeoJSON文件名", withExtension: "geojson")!
let shapeSource = MGLShapeSource(identifier: "polygon-source", url: geoJSONURL, options: nil)
mapView.style?.addSource(shapeSource)

// 创建并配置FillLayer
let fillLayer = MGLFillLayer(identifier: "polygon-layer", source: shapeSource)
fillLayer.isInteractive = true // 关键：开启图层交互
fillLayer.fillColor = UIColor.blue.withAlphaComponent(0.6)
mapView.style?.addLayer(fillLayer)

2. 实现MapView代理方法处理点击 #

让你的ViewController遵守MGLMapViewDelegate协议，实现专门的要素点击回调方法，直接获取被点击的多边形要素：

// 先设置代理
mapView.delegate = self

// 实现点击回调
func mapView(_ mapView: MGLMapView, didSelect annotationOrFeature: MGLAnnotation & MGLFeature) {
    // 过滤出当前目标图层的要素
    guard let feature = annotationOrFeature as? MGLFeature,
          feature.layerIdentifier == "polygon-layer" else {
        return
    }
    
    // 获取多边形的自定义属性（比如GeoJSON里的name、id等字段）
    let featureName = feature.attributes["name"] as? String ?? "未命名区域"
    
    // 示例：弹出弹窗展示信息
    let callout = MGLCalloutView()
    callout.titleText = featureName
    callout.subtitleText = "点击了该多边形"
    mapView.showCallout(for: annotationOrFeature, animated: true)
}

补充：处理其他手势（如长按） #

如果需要长按等其他交互，同样使用Mapbox提供的代理方法：

func mapView(_ mapView: MGLMapView, didLongPressOn mapPoint: MGLMapPoint, feature: MGLFeature?) {
    guard let feature = feature, feature.layerIdentifier == "polygon-layer" else { return }
    // 处理长按逻辑
}

内容的提问来源于stack exchange，提问作者nickcoding2