如何检查 LatLng 点是否位于 google maps android 上 geojson 层上的多边形内

Question

Currently, I am working on a location-based project. In this project I've added a GeoJsonLayer as below:

As can be seen in the image, the red marker is inside a box. Is there any way to check if the marker is inside a box (polygon) or not on google maps?

Inside the onMapReady() function I have added the GeoJson layer as follow: `

try {
    GeoJsonLayer layer = new GeoJsonLayer(mMap, R.raw.gokulpeth_area, MapsActivity.this);
    layer.getDefaultPolygonStyle().setStrokeColor(Color.WHITE);
    layer.addLayerToMap();
} catch (IOException | JSONException e) {
    e.printStackTrace();
}

` Please help me to achieve the task.

Answer 1

You can use containsLocation(double latitude, double longitude, java.util.List<LatLng> polygon, boolean geodesic) method from Maps SDK for Android Utility Library :

public static boolean containsLocation(double latitude, double longitude, java.util.List polygon, boolean geodesic)

Computes whether the given point lies inside the specified polygon. The polygon is always considered closed, regardless of whether the last point equals the first or not. Inside is defined as not containing the South Pole -- the South Pole is always outside. The polygon is formed of great ci rcle segments if geodesic is true, and of rhumb (loxodromic) segments otherwise.