我曾经使用 FusedLocationApi，直到我得知它已被弃用(请参阅下面的引用资料)。实现起来很简单。正如文档所说，您需要将它与 GoogleApiClient 结合使用

LocationServices.FusedLocationApi.requestLocationUpdates(googleApiClient,
                        locationRequest, this);

我最近更改为 FusedLocationProviderClient(请参阅下面的引用资料)按照教程，我能够成功地让 FusedLocationProviderClient 工作

教程:https://github.com/codepath/android_guides/wiki/Retrieving-Location-with-LocationServices-API

// new Google API SDK v11 uses getFusedLocationProviderClient(this)
getFusedLocationProviderClient(this).requestLocationUpdates(mLocationRequest, new LocationCallback() {
      @Override
      public void onLocationResult(LocationResult locationResult) {
         // do work here
         onLocationChanged(locationResult.getLastLocation();
      }
    },
    Looper.myLooper());

我遇到的问题是 Looper 线程。即使应用程序在后台，Looper 线程也会继续运行。我想在应用程序在后台时暂停位置更新，然后在应用程序在前台时恢复位置更新。我怎样才能做到这一点？

引用资料:

1. https://developers.google.com/android/reference/com/google/android/gms/location/FusedLocationProviderApi
2. https://developers.google.com/android/reference/com/google/android/gms/location/FusedLocationProviderClient

最佳答案

您只需在 Activity 的 onPause() 中调用 mFusedLocationClient.removeLocationUpdates(mLocationCallback)。然而，它的意义远不止于此。

在您的主要 Activity 中使用 FusedLocationProviderClient 和 LocationRequest 的成员变量:

import com.google.android.gms.location.FusedLocationProviderClient;
import com.google.android.gms.location.LocationCallback;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationResult;

public class MainActivity extends AppCompatActivity
        GoogleApiClient.ConnectionCallbacks,
        GoogleApiClient.OnConnectionFailedListener {

    FusedLocationProviderClient mFusedLocationClient;
    LocationRequest mLocationRequest;

    //..........

也为 LocationCallback 使用一个成员变量:

LocationCallback mLocationCallback = new LocationCallback(){
    @Override
    public void onLocationResult(LocationResult locationResult) {
        for (Location location : locationResult.getLocations()) {
            Log.i("MainActivity", "Location: " + location.getLatitude() + " " + location.getLongitude());

        }
    };

};

然后，在onCreate()中分配mFusedLocationClient:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    mFusedLocationClient = LocationServices.getFusedLocationProviderClient(this);
    requestLocationUpdates();

    //...............
}

然后在onResume()中，如果设置了FusedLocationProviderClient，则使用它。

@Override
public void onResume() {
    if (mFusedLocationClient != null) {
        requestLocationUpdates();
    }
}

public void requestLocationUpdates() {
    mLocationRequest = new LocationRequest();
    mLocationRequest.setInterval(120000); // two minute interval
    mLocationRequest.setFastestInterval(120000);
    mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
    if (ContextCompat.checkSelfPermission(this,
            Manifest.permission.ACCESS_FINE_LOCATION)
            == PackageManager.PERMISSION_GRANTED) {
        mFusedLocationClient.requestLocationUpdates(mLocationRequest, mLocationCallback, Looper.myLooper());
    }
}

最后，在 onPause() 中调用 removeLocationUpdates():

@Override
public void onPause() {
    super.onPause();
    if (mFusedLocationClient != null) {
        mFusedLocationClient.removeLocationUpdates(mLocationCallback);
    }
}

关于android - FusedLocationProviderClient 何时以及如何停止 Looper？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/46552087/