Check if a latitude and longitude is within a circle
What you basically need, is the distance between two points on the map:
float[] results = new float[1];
Location.distanceBetween(centerLatitude, centerLongitude, testLatitude, testLongitude, results);
float distanceInMeters = results[0];
boolean isWithin10km = distanceInMeters < 10000;
If you have already Location
objects:
Location center;
Location test;
float distanceInMeters = center.distanceTo(test);
boolean isWithin10km = distanceInMeters < 10000;
Here is the interesting part of the API used: https://developer.android.com/reference/android/location/Location.html
Check this:
private boolean isMarkerOutsideCircle(LatLng centerLatLng, LatLng draggedLatLng, double radius) {
float[] distances = new float[1];
Location.distanceBetween(centerLatLng.latitude,
centerLatLng.longitude,
draggedLatLng.latitude,
draggedLatLng.longitude, distances);
return radius < distances[0];
}