使位置离线

时间:2017-10-24 08:48:57

标签: android android-location android-gps

我希望在离线时获取当前locatoin的经度和纬度值,并将当前位置保存到其数据库中。当移动数据和wifi关闭但GPS开启时,是否可以获得设备的经度和纬度?

1 个答案:

答案 0 :(得分:10)

只需使用此代码即可。确保用户未在其位置设置中选择仅限wifi或仅选择网络。它必须是高精度或仅限GPS。这段代码将起作用。

public class Location extends AppCompatActivity {
LocationManager locationManager;
Context mContext;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_location);
    mContext=this;
    locationManager=(LocationManager) mContext.getSystemService(Context.LOCATION_SERVICE);
    locationManager.requestLocationUpdates( LocationManager.GPS_PROVIDER,
            2000,
            10, locationListenerGPS);
    isLocationEnabled();

}

LocationListener locationListenerGPS=new LocationListener() {
    @Override
    public void onLocationChanged(android.location.Location location) {
        double latitude=location.getLatitude();
        double longitude=location.getLongitude();
        String msg="New Latitude: "+latitude + "New Longitude: "+longitude;
        Toast.makeText(mContext,msg,Toast.LENGTH_LONG).show();
    }

    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) {

    }

    @Override
    public void onProviderEnabled(String provider) {

    }

    @Override
    public void onProviderDisabled(String provider) {

    }
};


protected void onResume(){
    super.onResume();
    isLocationEnabled();
}

private void isLocationEnabled() {

    if(!locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)){
        AlertDialog.Builder alertDialog=new AlertDialog.Builder(mContext);
        alertDialog.setTitle("Enable Location");
        alertDialog.setMessage("Your locations setting is not enabled. Please enabled it in settings menu.");
        alertDialog.setPositiveButton("Location Settings", new DialogInterface.OnClickListener(){
            public void onClick(DialogInterface dialog, int which){
                Intent intent=new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
                startActivity(intent);
            }
        });
        alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener(){
            public void onClick(DialogInterface dialog, int which){
                dialog.cancel();
            }
        });
        AlertDialog alert=alertDialog.create();
        alert.show();
    }
    else{
        AlertDialog.Builder alertDialog=new AlertDialog.Builder(mContext);
        alertDialog.setTitle("Confirm Location");
        alertDialog.setMessage("Your Location is enabled, please enjoy");
        alertDialog.setNegativeButton("Back to interface",new DialogInterface.OnClickListener(){
            public void onClick(DialogInterface dialog, int which){
                dialog.cancel();
            }
        });
        AlertDialog alert=alertDialog.create();
        alert.show();
    }
}
}

requestLocationUpdates方法的参数如下:

provider:我们要注册的提供者的名称。 minTime:位置更新之间的最小时间间隔(以毫秒为单位)。 minDistance:位置更新之间的最小距离(以米为单位)。 listener:一个LocationListener,它的onLocationChanged(Location)方法将为每个位置更新调用。

权限:

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />

为低于棒棒糖的版本添加以上权限,以及为marshmallow及更高版本添加运行时权限。