如何使用FusedLocation API每5分钟接收一次位置更新

Question

我目前正在开发一个应用程序,它必须每五分钟检查一次用户的位置并将坐标发送到服务器.我决定使用Google Play服务中的FusedLocation API而不是普通的旧BitManager API,主要是因为我注意到了LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY优先级,声称提供100米精度等级且电池使用合理,这正是我需要.

在我的例子中,我有一个Activity,其继承结构是:

public class MainActivity extends AppCompatActivity implements
        GoogleApiClient.ConnectionCallbacks,
        GoogleApiClient.OnConnectionFailedListener, LocationListener

并实现相关的回调(onConnected,onConnectionFailed,onConnectionSuspended,onLocationChanged).根据官方文档的建议,我还使用此方法获取了GoogleApiClient的实例:

protected synchronized GoogleApiClient buildGoogleApiClient() {
        return new GoogleApiClient.Builder(this).addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API).build();

在onConnected中,我使用启动位置更新

LocationServices.FusedLocationApi.requestLocationUpdates(mApiClient,
                mLocationRequest, this);

...并捕获onLocationChanged()中的更改.

但是,我很快发现位置更新似乎在一段时间后停止了.也许是因为这个方法与Activity生命周期有关,我不确定.无论如何,我试图通过创建一个扩展IntentService并由AlarmManager启动的内部类来解决这个问题.所以在onConnected中,我最终做到了这一点:

AlarmManager alarmMan = (AlarmManager) this
                .getSystemService(Context.ALARM_SERVICE);

        Intent updateIntent = new Intent(this, LocUpService.class);

        PendingIntent pIntent = PendingIntent.getService(this, 0, updateIntent,
                PendingIntent.FLAG_UPDATE_CURRENT);
        alarmMan.setRepeating(AlarmManager.ELAPSED_REALTIME_WAKEUP, 0,
                1000 * 60 * 5, pIntent);

LocUpService类如下所示:

public static class LocUpService extends IntentService {

        public LocUpService() {
            super("LocUpService");

        }

        @Override
        protected void onHandleIntent(Intent intent) {
            Coords coords = LocationUpdater.getLastKnownLocation(mApiClient);


        }

    }

LocationUpdater是另一个类,它包含静态方法getLastKnownLocation,它是这样的:

public static Coords getLastKnownLocation(GoogleApiClient apiClient) {

        Coords coords = new Coords();
        Location location = LocationServices.FusedLocationApi
                .getLastLocation(apiClient);

        if (location != null) {

            coords.setLatitude(location.getLatitude());
            coords.setLongitude(location.getLongitude());

            Log.e("lat ", location.getLatitude() + " degrees");
            Log.e("lon ", location.getLongitude() + " degrees");

        }
        return coords;
    }

但是惊喜!! 我得到"IllegalArgumentException:GoogleApiClient参数是必需的",当我清楚地传递对静态方法的引用时,我认为必须与GoogleApiClient实例有关的事件与Activity的生命周期有关,并且将实例传递给IntentService.

所以我在想:如何每五分钟定期更新一次而不会发疯？我是否扩展服务,在该组件上实现所有接口回调,在那里构建GoogleApiClient实例并使其在后台运行？我是否有一个AlarmManager启动一个服务,每隔五分钟就会扩展一次IntentService来完成工作,再次在IntentService中构建所有相关的回调和GoogleApiClient？我是否一直在做我现在正在做的事情但是将GoogleApiClient构建为单身人士,期待它会有所作为？你会怎么做？

谢谢,对不起,这是如此啰嗦.

Answer 1

我目前正在开发一个应用程序,它必须每五分钟检查一次用户的位置并将坐标发送到服务器.我决定使用Google Play Services中的FusedLocation API而不是普通的旧LocationManager API

我们的应用程序具有完全相同的要求,我在几天前实现了这一点,我就是这样做的.

在启动活动中或您要启动的任何位置,使用AlarmManager将LocationTracker配置为每5分钟运行一次.

private void startLocationTracker() {
    // Configure the LocationTracker's broadcast receiver to run every 5 minutes.
    Intent intent = new Intent(this, LocationTracker.class);
    AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
    PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0, intent, 0);
    alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, Calendar.getInstance().getTimeInMillis(),
            LocationProvider.FIVE_MINUTES, pendingIntent);
}

LocationTracker.java

public class LocationTracker extends BroadcastReceiver {

    private PowerManager.WakeLock wakeLock;

    @Override
    public void onReceive(Context context, Intent intent) {
        PowerManager pow = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
        wakeLock = pow.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "");
        wakeLock.acquire();

        Location currentLocation = LocationProvider.getInstance().getCurrentLocation();

        // Send new location to backend. // this will be different for you
        UserService.registerLocation(context, new Handlers.OnRegisterLocationRequestCompleteHandler() {
            @Override
            public void onSuccess() {
                Log.d("success", "UserService.RegisterLocation() succeeded");

                wakeLock.release();
            }

            @Override
            public void onFailure(int statusCode, String errorMessage) {
                Log.d("error", "UserService.RegisterLocation() failed");
                Log.d("error", errorMessage);

                wakeLock.release();
            }
        }, currentLocation);
    }
}

LocationProvider.java

public class LocationProvider {

    private static LocationProvider instance = null;
    private static Context context;

    public static final int ONE_MINUTE = 1000 * 60;
    public static final int FIVE_MINUTES = ONE_MINUTE * 5;

    private static Location currentLocation;

    private LocationProvider() {

    }

    public static LocationProvider getInstance() {
        if (instance == null) {
            instance = new LocationProvider();
        }

        return instance;
    }

    public void configureIfNeeded(Context ctx) {
        if (context == null) {
            context = ctx;
            configureLocationUpdates();
        }
    }

    private void configureLocationUpdates() {
        final LocationRequest locationRequest = createLocationRequest();
        final GoogleApiClient googleApiClient = new GoogleApiClient.Builder(context)
                .addApi(LocationServices.API)
                .build();

        googleApiClient.registerConnectionCallbacks(new GoogleApiClient.ConnectionCallbacks() {
            @Override
            public void onConnected(Bundle bundle) {
                startLocationUpdates(googleApiClient, locationRequest);
            }

            @Override
            public void onConnectionSuspended(int i) {

            }
        });
        googleApiClient.registerConnectionFailedListener(new GoogleApiClient.OnConnectionFailedListener() {
            @Override
            public void onConnectionFailed(ConnectionResult connectionResult) {

            }
        });

        googleApiClient.connect();
    }

    private static LocationRequest createLocationRequest() {
        LocationRequest locationRequest = new LocationRequest();
        locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
        locationRequest.setInterval(FIVE_MINUTES);
        return locationRequest;
    }

    private static void startLocationUpdates(GoogleApiClient client, LocationRequest request) {
        LocationServices.FusedLocationApi.requestLocationUpdates(client, request, new com.google.android.gms.location.LocationListener() {
            @Override
            public void onLocationChanged(Location location) {
                currentLocation = location;
            }
        });
    }

    public Location getCurrentLocation() {
        return currentLocation;
    }
}

我首先在扩展应用程序的类中创建LocationProvider的实例,在启动应用程序时创建实例:

MyApp.java

public class MyApp extends Application {

    @Override
    public void onCreate() {
        super.onCreate();

        LocationProvider locationProvider = LocationProvider.getInstance();
        locationProvider.configureIfNeeded(this);
    }
}

LocationProvider实例化并配置为位置更新一次,因为它是一个单例.每隔5分钟,它将更新其currentLocation值,我们可以从我们需要的任何地方检索它

Location loc = LocationProvider.getInstance().getCurrentLocation();

不需要运行任何类型的后台服务.AlarmManager将每5分钟向LocationTracker.onReceive()广播一次,部分唤醒锁将确保即使设备处于待机状态,代码也将完成运行.这也是节能的.

请注意,您需要以下权限

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

<!-- For keeping the LocationTracker alive while it is doing networking -->
<uses-permission android:name="android.permission.WAKE_LOCK" />

并且不要忘记注册接收者:

<receiver android:name=".LocationTracker" />