我们正在开发移动跟踪应用。对于位置更新,Fused location API以高精度作为优先级使用。
即使屏幕关闭,也需要更新位置。所以,我们使用的是背景Service
。后台Service
也获取部分WakeLock
,以便设备不会进入休眠状态。
在后台Service
,我们使用Service
的待定更新请求位置更新。
问题是我们只在屏幕打开时接收位置更新。一旦屏幕关闭,位置更新就会停止。此外,Thread
运行Service
,任何时候都不会被杀死。
当屏幕关闭BroadcastReceiver
时再次创建位置请求也不起作用。
以下是背景Service
类(RouteExecution
):
private static final String TAG = "RouteExecution";
private static RouteExecution routeExecution = null;
private static GoogleApiClient mGoogleApiClient;
private static PendingIntent pendingIntent = null;
private PowerManager.WakeLock waitLock;
/**
* Creates an IntentService. Invoked by your subclass's constructor.
*/
public RouteExecution() {
super(TAG);
RouteExecution.routeExecution = this;
}
@Override
public void onCreate() {
super.onCreate();
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addApi(LocationServices.API)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.build();
mGoogleApiClient.connect();
IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_ON);
filter.addAction(Intent.ACTION_SCREEN_OFF);
BroadcastReceiver mReceiver = new PowerButtonReceiver();
registerReceiver(mReceiver, filter);
PowerManager powerManager = (PowerManager) getSystemService(Context.POWER_SERVICE);
waitLock = powerManager.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, TAG);
waitLock.acquire();
}
@Override
protected void onHandleIntent(Intent intent) {
if (LocationResult.hasResult(intent)) {
LocationResult locationResult = LocationResult.extractResult(intent);
Location location = locationResult.getLastLocation();
GPSLocation gpsLocation = new GPSLocation(location);
Log.d(TAG, "Location Accuracy: " + location.getAccuracy() + " "
+ " has: " + location.hasAccuracy() + " Provider: " + location.getProvider()
+ " long: " + location.getLongitude() + " lat: " + location.getLatitude());
}
}
public boolean checkLocationPermission() {
if (ActivityCompat.checkSelfPermission(routeExecution, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED
&& ActivityCompat.checkSelfPermission(routeExecution, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return false;
}
return true;
}
public void createLocationListener() {
if (!this.checkLocationPermission()) {
return;
}
LocationRequest mLocationRequest = LocationRequest.create();
mLocationRequest.setInterval(5000);
mLocationRequest.setFastestInterval(5000);
mLocationRequest.setSmallestDisplacement(0);
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
PendingResult<Status> statusPendingResult = LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient,
mLocationRequest, pendingIntent);
}
@Override
public void onConnected(@Nullable Bundle bundle) {
Log.d(TAG, mGoogleApiClient.isConnected() + " On Connected");
synchronized (this) {
createLocationListener();
}
}
public static GoogleApiClient getmGoogleApiClient() {
return mGoogleApiClient;
}
@Override
public void onDestroy() {
super.onDestroy();
waitLock.release();
mGoogleApiClient.disconnect();
}
public static RouteExecution getRouteExecution() {
return routeExecution;
}
public static void setPendingIntent(PendingIntent pendingIntent) {
RouteExecution.pendingIntent = pendingIntent;
}
Service
使用AlarmManager
开始。这是提取:
AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
Intent updateServiceIntent = new Intent(context, RouteExecution.class);
PendingIntent pendingUpdateIntent = PendingIntent.getService(context, 0, updateServiceIntent, 0);
RouteExecution.setPendingIntent(pendingUpdateIntent);
alarmManager.set(AlarmManager.RTC_WAKEUP, 50000, pendingUpdateIntent);
BroadcastReceiver
:
public class PowerButtonReceiver extends BroadcastReceiver {
private static final String TAG = "PowerButton";
@Override
public void onReceive(Context context, Intent intent) {
Log.d(TAG, "Power Button");
if (RouteExecution.getRouteExecution() != null) {
RouteExecution.getRouteExecution().createLocationListener();
}
}
}
即使屏幕关闭,如何继续获取位置更新。
感谢您的帮助。
答案 0 :(得分:1)
首先,在WakeLock
中查询Service
根本不可靠。该代码执行之前,设备可以重新进入休眠状态。
我会拨打PendingIntent.getBroadcast()
而不是PendingIntent.getService()
,因为WakeLock
在技术上保证onReceive()
,并从那里开始Service
。
在WakeLock
中获取onReceive()
,在适当时启动Service
并从WakeLock
发布Service
或
使用基本相同的WakefulBroadcastReceiver
,而不必自己实现大部分逻辑。
另一个可能的问题是在Marshmallow设备上使用AlarmManager.set()
。
如果Doze处于活动状态,则不会在这些设备上触发此方法设置的警报。
在API级别23 +上使用setAndAllowWhileIdle()
代替set()
。