/**
     * 计算两点的距离
     *
     * @param fromPoint
     * @param toPoint
     * @return 返回String类型带距离单位
     */
    public static String measureDistanceStr(LatLng fromPoint, LatLng toPoint) {
        String distanceStr = "";
        if (fromPoint != null && toPoint != null) {
            long distance = MapUtil.measureDistance(fromPoint, toPoint);
            if (distance >= 1000) {
                if (distance % 1000 == 0) {
                    distanceStr = distance / 1000 + "km";
                } else {
                    if ((distance % 1000 + "").length() < 3) {
                        distanceStr = distance / 1000 + ".0km";
                    } else {
                        long l1 = (distance % 1000) / 100;
                        distanceStr = distance / 1000 + "." + l1 + "km";
                    }
                }
            } else {
                distanceStr = distance + "m";
            }
        }
        return distanceStr;
    }

    //测量两点的距离
    public static long measureDistance(LatLng fromPoint, LatLng toPoint) {
        double EARTH_RADIUS = 6378137;
        long distance = 0;
        double startLongitude = fromPoint.longitude;
        double startLatitude = fromPoint.latitude;
        double endLongitude = toPoint.longitude;
        double endLatitude = toPoint.latitude;
        double radLatitude1 = startLatitude * Math.PI / 180.0;
        double radLatitude2 = endLatitude * Math.PI / 180.0;
        double a = Math.abs(radLatitude1 - radLatitude2);
        double b = Math.abs(startLongitude * Math.PI / 180.0 - endLongitude * Math.PI / 180.0);
        double s = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(a / 2), 2)
                + Math.cos(radLatitude1) * Math.cos(radLatitude2) * Math.pow(Math.sin(b / 2), 2)));
        s = s * EARTH_RADIUS;
        distance = Math.round(s * 10000) / 10000; // 返回距离单位是米
        return distance;
    }