Android上的LocationManager API似乎对一个只需要偶尔粗略估计用户位置的应用程序来说有点麻烦。
我正在开发的应用程序本身并不是一个定位应用程序，但它确实需要获取用户的位置，以便显示附近企业的列表。它不需要担心用户是否在移动或类似的事情。
以下是我想做的：
向用户显示附近位置的列表。预加载用户的位置，以便在“活动X”中需要它时，它将可用。我并不特别关心更新的准确性或频率。只要不太远，只要抓住一个位置就足够了。也许如果我想变得更漂亮，我会每隔几分钟左右更新一次位置，但这不是一个很大的优先事项。适用于任何具有GPS或网络位置提供商的设备。
这似乎并不难，但在我看来，我必须组建两个不同的位置提供商（GPS和NETWORK），并管理每个提供商的生命周期。不仅如此，我还必须在多个活动中复制相同的代码以满足#2。过去，我曾尝试使用getBestProvider（）将解决方案简化为仅使用一个位置提供程序，但这似乎只提供了最好的“理论”提供程序，而不是实际会为您提供最佳结果的提供程序。
有没有更简单的方法来实现这一点？
当前回答
实际上，我们可以使用两个提供商（GPS和网络）。他们只是分享一个公共听众：
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 10 * 1000, (float) 10.0, listener);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 90 * 1000, (float) 10.0, listener);
这是必要的，因为总是需要及时调用OnLocationChanged（）方法。
其他回答
看到所有答案后，提出问题（最简单、最稳健）。我只点击了图书馆Android ReactiveLocation。
当我制作一个位置跟踪应用程序时。然后我意识到，通过优化电池处理位置跟踪是非常典型的。
所以我想告诉新手和开发者，他们不想在未来的优化中维护他们的位置代码。使用此库。
ReactiveLocationProvider locationProvider = new
ReactiveLocationProvider(context);
locationProvider.getLastKnownLocation()
.subscribe(new Consumer<Location>() {
@Override
public void call(Location location) {
doSthImportantWithObtainedLocation(location);
}
});
要放入应用程序级别build.gradle的依赖项
dependencies {
...
compile 'pl.charmas.android:android-reactive-location2:2.1@aar'
compile 'com.google.android.gms:play-services-location:11.0.4' //you can use newer GMS version if you need
compile 'com.google.android.gms:play-services-places:11.0.4'
compile 'io.reactivex:rxjava:2.0.5' //you can override RxJava version if you need
}
使用此库的优点：
现在和将来都将积极维护这种自由。您不必担心电池优化。因为开发人员已经尽力了。易于安装，放置依赖项和播放。轻松连接到Play Services API获取最后一个已知位置订阅位置更新使用位置设置API管理地理围栏地址列表的地理编码位置活动识别使用当前位置API获取位置自动完成建议
尽管这里已经给出了答案。我只是想向全世界分享这一点，以防遇到这种情况。
我的要求是，我需要在最长30到35秒内获取用户的当前位置，所以下面是我根据Nirav Ranpara的回答制定的解决方案。
1.我制作了MyLocationManager.java类，该类处理所有GPS和网络内容
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
import com.app.callbacks.OnLocationDetectectionListener;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.provider.Settings;
import android.util.Log;
import android.widget.Toast;
public class MyLocationManager {
/** The minimum distance to GPS change Updates in meters **/
private final long MIN_DISTANCE_CHANGE_FOR_UPDATES_FOR_GPS = 2; // 2
// meters
/** The minimum time between GPS updates in milliseconds **/
private final long MIN_TIME_BW_UPDATES_OF_GPS = 1000 * 5 * 1; // 5
// seconds
/** The minimum distance to NETWORK change Updates in meters **/
private final long MIN_DISTANCE_CHANGE_FOR_UPDATES_FOR_NETWORK = 5; // 5
// meters
/** The minimum time between NETWORK updates in milliseconds **/
private final long MIN_TIME_BW_UPDATES_OF_NETWORK = 1000 * 10 * 1; // 10
// seconds
/**
* Lets just say i don't trust the first location that the is found. This is
* to avoid that
**/
private int NetworkLocationCount = 0, GPSLocationCount = 0;
private boolean isGPSEnabled;
private boolean isNetworkEnabled;
/**
* Don't do anything if location is being updated by Network or by GPS
*/
private boolean isLocationManagerBusy;
private LocationManager locationManager;
private Location currentLocation;
private Context mContext;
private OnLocationDetectectionListener mListener;
public MyLocationManager(Context mContext,
OnLocationDetectectionListener mListener) {
this.mContext = mContext;
this.mListener = mListener;
}
/**
* Start the location manager to find my location
*/
public void startLocating() {
try {
locationManager = (LocationManager) mContext
.getSystemService(Context.LOCATION_SERVICE);
// Getting GPS status
isGPSEnabled = locationManager
.isProviderEnabled(LocationManager.GPS_PROVIDER);
// Getting network status
isNetworkEnabled = locationManager
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!isGPSEnabled && !isNetworkEnabled) {
// No network provider is enabled
showSettingsAlertDialog();
} else {
// If GPS enabled, get latitude/longitude using GPS Services
if (isGPSEnabled) {
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES_OF_GPS,
MIN_DISTANCE_CHANGE_FOR_UPDATES_FOR_GPS,
gpsLocationListener);
}
if (isNetworkEnabled) {
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER,
MIN_TIME_BW_UPDATES_OF_NETWORK,
MIN_DISTANCE_CHANGE_FOR_UPDATES_FOR_NETWORK,
networkLocationListener);
}
}
/**
* My 30 seconds plan to get myself a location
*/
ScheduledExecutorService se = Executors
.newSingleThreadScheduledExecutor();
se.schedule(new Runnable() {
@Override
public void run() {
if (currentLocation == null) {
if (isGPSEnabled) {
currentLocation = locationManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER);
} else if (isNetworkEnabled) {
currentLocation = locationManager
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
}
if (currentLocation != null && mListener != null) {
locationManager.removeUpdates(gpsLocationListener);
locationManager
.removeUpdates(networkLocationListener);
mListener.onLocationDetected(currentLocation);
}
}
}
}, 30, TimeUnit.SECONDS);
} catch (Exception e) {
Log.e("Error Fetching Location", e.getMessage());
Toast.makeText(mContext,
"Error Fetching Location" + e.getMessage(),
Toast.LENGTH_SHORT).show();
}
}
/**
* Handle GPS location listener callbacks
*/
private LocationListener gpsLocationListener = new LocationListener() {
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
@Override
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onLocationChanged(Location location) {
if (GPSLocationCount != 0 && !isLocationManagerBusy) {
Log.d("GPS Enabled", "GPS Enabled");
isLocationManagerBusy = true;
currentLocation = location;
locationManager.removeUpdates(gpsLocationListener);
locationManager.removeUpdates(networkLocationListener);
isLocationManagerBusy = false;
if (currentLocation != null && mListener != null) {
mListener.onLocationDetected(currentLocation);
}
}
GPSLocationCount++;
}
};
/**
* Handle Network location listener callbacks
*/
private LocationListener networkLocationListener = new LocationListener() {
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
@Override
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onLocationChanged(Location location) {
if (NetworkLocationCount != 0 && !isLocationManagerBusy) {
Log.d("Network", "Network");
isLocationManagerBusy = true;
currentLocation = location;
locationManager.removeUpdates(gpsLocationListener);
locationManager.removeUpdates(networkLocationListener);
isLocationManagerBusy = false;
if (currentLocation != null && mListener != null) {
mListener.onLocationDetected(currentLocation);
}
}
NetworkLocationCount++;
}
};
/**
* Function to show settings alert dialog. On pressing the Settings button
* it will launch Settings Options.
* */
public void showSettingsAlertDialog() {
AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);
// Setting Dialog Title
alertDialog.setTitle("GPS is settings");
// Setting Dialog Message
alertDialog
.setMessage("GPS is not enabled. Do you want to go to settings menu?");
// On pressing the Settings button.
alertDialog.setPositiveButton("Settings",
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Intent intent = new Intent(
Settings.ACTION_LOCATION_SOURCE_SETTINGS);
mContext.startActivity(intent);
}
});
// On pressing the cancel button
alertDialog.setNegativeButton("Cancel",
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
// Showing Alert Message
alertDialog.show();
}
}
2.我创建了一个接口（回调）OnLocationDetectionListener.java，以便将结果传递回调用片段或活动
import android.location.Location;
public interface OnLocationDetectectionListener {
public void onLocationDetected(Location mLocation);
}
3.然后我制作了一个MainAppActivty.java Activity，它实现了OnLocationDetectionListener接口，下面是我如何在其中接收位置
public class MainAppActivty extends Activity implements
OnLocationDetectectionListener {
private Location currentLocation;
private MyLocationManager mLocationManager;
@Override
protected void onCreate(Bundle savedInstanceState) {
setContentView(R.layout.activity_home);
super.onCreate(savedInstanceState);
mLocationManager = new MyLocationManager(this, this);
mLocationManager.startLocating();
}
@Override
public void onLocationDetected(Location mLocation) {
//Your new Location is received here
currentLocation = mLocation;
}
4.将以下权限添加到清单文件
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
希望这对其他人有帮助：）
你可以一直使用LocationManager.getLastKnownLocation（），但就像它说的那样，它可能已经过时了。
获取一般位置的一个简单方法是注册网络（通常很快）。
LocationManager locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER, 1000, 1000, this);
然后做
locationManager.removeUpdates(this);
在侦听器的onLocationChanged（）方法中。
我不确定基于位置的服务是否可以从GPS以外的其他基础设施获取位置，但根据那篇文章，这似乎是可能的：
应用程序可以调用几种类型的定位方法。使用移动电话网络：当前单元格ID可用于识别基站收发信机（BTS）设备正在通信以及该BTS的位置。显然，这种方法的准确性取决于单元格的大小，以及可能非常不准确。GSM蜂窝可以是2到20直径千米。另外与细胞ID一起使用的技术可以精度在150米以内。使用卫星：全球定位系统（GPS），受控美国国防部使用由24颗卫星组成的星座围绕地球运行。GPS确定通过计算设备的位置时间差信号来自不同的卫星到达接受者GPS信号是编码的，所以移动设备必须配备使用GPS接收器。GPS是可能是最准确的方法（如果GPS接收机具有清晰的天空视图），但它也有一些缺点：硬件可能很昂贵电池使用时，需要冷启动后的热身对可见卫星的初步定位。它还受到“峡谷效应”的影响在城市，卫星能见度是间歇性的。使用短程定位信标：相对小面积，如单个建筑，局域网可以提供其他位置服务。例如，适当地配备的设备可以使用蓝牙短程定位。
Kotlin版本的@Fedor Greate回答：
类的用法：
val locationResult = object : MyLocation.LocationResult() {
override fun gotLocation(location: Location?) {
val lat = location!!.latitude
val lon = location.longitude
Toast.makeText(context, "$lat --SLocRes-- $lon", Toast.LENGTH_SHORT).show()
}
}
val myLocation = MyLocation()
myLocation.getLocation(inflater.context, locationResult)
MyLocation类：
class MyLocation {
internal lateinit var timer1: Timer
internal var lm: LocationManager? = null
internal lateinit var locationResult: LocationResult
internal var gps_enabled = false
internal var network_enabled = false
internal var locationListenerGps: LocationListener = object : LocationListener {
override fun onLocationChanged(location: Location) {
timer1.cancel()
locationResult.gotLocation(location)
lm!!.removeUpdates(this)
lm!!.removeUpdates(locationListenerNetwork)
}
override fun onProviderDisabled(provider: String) {}
override fun onProviderEnabled(provider: String) {}
override fun onStatusChanged(provider: String, status: Int, extras: Bundle) {}
}
internal var locationListenerNetwork: LocationListener = object : LocationListener {
override fun onLocationChanged(location: Location) {
timer1.cancel()
locationResult.gotLocation(location)
lm!!.removeUpdates(this)
lm!!.removeUpdates(locationListenerGps)
}
override fun onProviderDisabled(provider: String) {}
override fun onProviderEnabled(provider: String) {}
override fun onStatusChanged(provider: String, status: Int, extras: Bundle) {}
}
fun getLocation(context: Context, result: LocationResult): Boolean {
//I use LocationResult callback class to pass location value from MyLocation to user code.
locationResult = result
if (lm == null)
lm = context.getSystemService(Context.LOCATION_SERVICE) as LocationManager?
//exceptions will be thrown if provider is not permitted.
try {
gps_enabled = lm!!.isProviderEnabled(LocationManager.GPS_PROVIDER)
} catch (ex: Exception) {
}
try {
network_enabled = lm!!.isProviderEnabled(LocationManager.NETWORK_PROVIDER)
} catch (ex: Exception) {
}
//don't start listeners if no provider is enabled
if (!gps_enabled && !network_enabled)
return false
if (ActivityCompat.checkSelfPermission(context,
Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED ||
ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) run {
ActivityCompat.requestPermissions(context as Activity,
arrayOf(Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION), 111)
}
if (gps_enabled)
lm!!.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0f, locationListenerGps)
if (network_enabled)
lm!!.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0f, locationListenerNetwork)
timer1 = Timer()
timer1.schedule(GetLastLocation(context), 20000)
return true
}
internal inner class GetLastLocation(var context: Context) : TimerTask() {
override fun run() {
lm!!.removeUpdates(locationListenerGps)
lm!!.removeUpdates(locationListenerNetwork)
var net_loc: Location? = null
var gps_loc: Location? = null
if (ActivityCompat.checkSelfPermission(context,
Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED ||
ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED
) run {
ActivityCompat.requestPermissions(context as Activity,
arrayOf(Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION),111)
}
if (gps_enabled)
gps_loc = lm!!.getLastKnownLocation(LocationManager.GPS_PROVIDER)
if (network_enabled)
net_loc = lm!!.getLastKnownLocation(LocationManager.NETWORK_PROVIDER)
//if there are both values use the latest one
if (gps_loc != null && net_loc != null) {
if (gps_loc.getTime() > net_loc.getTime())
locationResult.gotLocation(gps_loc)
else
locationResult.gotLocation(net_loc)
return
}
if (gps_loc != null) {
locationResult.gotLocation(gps_loc)
return
}
if (net_loc != null) {
locationResult.gotLocation(net_loc)
return
}
locationResult.gotLocation(null)
}
}
abstract class LocationResult {
abstract fun gotLocation(location: Location?)
}
}
