百度地图Android(安卓)SQLITE在本地如何实现按距离排序、范围查找

在Android客户端上实现按距离排序，需要使用javase数组工具类和集合工具类中提供的sort方法，sort就是使用Comparator接口来处理排序。

Arrays.sort(T[],Comparator<? super T> c);Collections.sort(List list,Comparator<? super T> c);

// 自定义比较器：    private static class SbLocationComparator implements Comparator {        private LatLng pCenter;        SbLocationComparator(LatLng pCenter) {            this.pCenter = pCenter;        }        public int compare(Object object1, Object object2) {// 实现接口中的方法            SbLocation p1 = (SbLocation) object1;            int distance1 = (int) DistanceUtil.getDistance2(pCenter.latitude, pCenter.longitude,                    Double.valueOf(p1.getLatitude()),                    Double.valueOf(p1.getLongitude()));            SbLocation p2 = (SbLocation) object2;            int distance2 = (int) DistanceUtil.getDistance2(pCenter.latitude, pCenter.longitude,                    Double.valueOf(p2.getLatitude()),                    Double.valueOf(p2.getLongitude()));            //L.d("compare:+distance1=>" + distance1 + " distance2=>" + distance2);            return distance1 - distance2;        }    }

import java.text.DecimalFormat;public class DistanceUtil {    // 地球平均半径    private static final double EARTH_RADIUS = 6378137;    // 把经纬度转为度（°）    private static double rad(double d) {        return d * Math.PI / 180.0;    }    /**     * 根据两点间经纬度坐标（double值），计算两点间距离，单位：千米     * @author ershuai     * @param lng1     * @param lat1     * @param lng2     * @param lat2     * @return     */    public static double getDistance(double lng1, double lat1, double lng2, double lat2) {        double radLat1 = rad(lat1);        double radLat2 = rad(lat2);        double a = radLat1 - radLat2;        double b = rad(lng1) - rad(lng2);        double s = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(a / 2), 2) + Math.cos(radLat1) * Math.cos(radLat2) * Math.pow(Math.sin(b / 2), 2)));        s = s * EARTH_RADIUS;        s = s / 1000;        DecimalFormat df = new DecimalFormat("#.00");        s = Double.parseDouble(df.format(s));        return s;    }/**     * 根据两点间经纬度坐标（double值），计算两点间距离，单位：千米     * @author ershuai     * @param pCenter_latitude     * @param pCenter_longitude     * @param latitude     * @param longitude     * @return     */    public static double getDistance2(double pCenter_latitude,double pCenter_longitude,double latitude,double longitude) {        double radLat1 = rad(pCenter_latitude);        double radLat2 = rad(latitude);        double a = radLat1 - radLat2;        double b = rad(pCenter_longitude) - rad(longitude);        double s = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(a / 2), 2) + Math.cos(radLat1) * Math.cos(radLat2) * Math.pow(Math.sin(b / 2), 2)));        s = s * EARTH_RADIUS;        return s;    }    public static void main(String[] args) {        double distance1 = getDistance(104.046115, 30.6030110000, 104.074666, 30.611842);        System.out.println("Distance is: " + distance1 + " km");    }}

LatLng pCenter//输入中心点
Collections.sort(trandomList, new SbLocationComparator(pCenter));

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