Google Maps Android 从 GeoJsonFeature 获取 LatLng 点数组

Question

单击作为 geojson 功能的线时，如何获取点列表？我需要访问每条线的各个点吗？这不起作用：lineStringFeature.getPolylineOptions().getPoints()。非常感谢。

// Set a listener for geometry clicked events.
layer.setOnFeatureClickListener(new GeoJsonLayer.OnFeatureClickListener() {
    @Override
    public void onFeatureClick(Feature feature) {
        GeoJsonFeature lineStringFeature;
        GeoJsonLineStringStyle lineStringStyle = new GeoJsonLineStringStyle();
        lineStringFeature = (GeoJsonFeature) feature;
        lineStringStyle.setColor(Color.GREEN);
        lineStringStyle.setZIndex(10f);
        lineStringStyle.setWidth(6f);
        lineStringFeature.setLineStringStyle(lineStringStyle);

        // this doesn't work how do you get an array of LatLngs
        lineStringFeature.getPolylineOptions().getPoints().get(0);
    }
}

Answer 1

GeoJsonFeature 对象有一个 getGeometry() 方法返回几何（如果你确定类型，你可以将它转换为 GeoJsonLineString），GeoJsonLineString 对象有一个 getCoordinates() 方法返回带有坐标的List<LatLng>：

if ("LineString".equalsIgnoreCase(lineStringFeature.getGeometry().getType())) {
    List<LatLng> coordinates = ((GeoJsonLineString) lineStringFeature.getGeometry()).getCoordinates();
    // Do something with the coordinates
} else if ("MultiLineString".equalsIgnoreCase(lineStringFeature.getGeometry().getType())) {
    for (GeoJsonLineString linestring : ((GeoJsonMultilineString) lineStringFeature.getGeometry()).getLineStrings()) {
        List<LatLng> coordinates = linestring.getCoordinates();
        // Do something with the coordinates. Take into account that one MultiLinestring is composed of several Linestrings
    }
}