android gnss 框架在Android中, gps 数据通过gnss location框架获取，Location以分层的方式实现, 从上到下依次为
应用框架: 提供android.location API
定位管理器: LocationManager定位提供者: LocationProvider位置信息: Location定位监听者: LocationListener
Framework Services: 服务实现, 主要涉及文件如下
frameworks/base/location/java/android/location/*frameworks/base/services/core/java/com/android/server/location/*frameworks/base/services/core/java/com/android/server/LocationManagerService.javaframeworks/base/services/core/java/com/android/server/location/GnssLocationProvider.java
JNI: 封装GNSS hal层接口(IGnss)给GnssLocationProvider使用体现
frameworks/base/services/core/jni/com_android_server_location_GnssLocationProvider.cpp
HAL层: 实现了IGnss接口和IGnss服务
hardware/libhardware/include/hardware/gps.h
hardware/interfaces/gnss/1.0/ ====>android.hardware.gnss@1.0.sohardware/interfaces/gnss/1.0/default/ ====>android.hardware.gnss@1.0-impl.so android.hardware.gnss@1.0-service
hardware/interfaces/gnss/1.1/ ====>android.hardware.gnss@1.1.sohardware/interfaces/gnss/1.1/default/ ====>android.hardware.gnss@1.1-service
gps 用法VIM3 板子在安卓9上已经集成usb gps 功能，通过usb接口插入gps 接收器，然后安装gps apk，可以查看当前位置的经纬度等信息，也可以安装地图软件查看定位
注意1) 从GPS模块启动到获取第一次定位数据，可能需要比较长的时间2) 在没有网络的情况下也能使用，但是gps设备需要放置在室外才能接收到卫星信号
使用gps定位，需要先打开设置中的Location 开关，Droid Settings > More settings > Device Preferences > Loacation,Location 选择 on,命令查看location_providers_allowed 将为gps
123130|console:/ $ settings list secure |grep location_providers_allowed location_providers_allowed=gpsconsole:/ $
apk 运行如下
android gps 位置数据api 说明android frameworks 中封装了标准的api让应用去获取gps相关的数据，比如经纬度数据通过frameworks/base/location/java/android/location/Location.java这个类中的方法去获取，具体可以参考安卓源代码frameworks/base/tests/LocationTracker中的实现，Location 中获取经纬度api 如下
123456789101112131415161718192021583 /**584 * Get the latitude, in degrees.585 *586 *
All locations generated by the {@link LocationManager}587 * will have a valid latitude.588 */589 public double getLatitude() {590 return mLatitude;591 }600 /**601 * Get the longitude, in degrees.602 *603 *
All locations generated by the {@link LocationManager}604 * will have a valid longitude.605 */606 public double getLongitude() {607 return mLongitude;608 }
经纬度信息由GnssLocationProvider提供，如下
1201-01 13:11:01.483 3735 3757 I GnssLocationProvider: WakeLock released by handleMessage(REPORT_LOCATION, 1, Location[gps 22.570539,113.863433 hAcc=1 et=+6m35s993ms alt=153.4 vel=0.03909778 vAcc=??? sAcc=??? bAcc=??? {Bundle[{satellites=6, maxCn0=33, meanCn0=22}]}])
22.570539,113.863433 分别代表的是经纬度数据