我必须在某段时间内将firebase数据库保存到当前位置，这不仅在我的应用程序正在运行时，而且在关闭时也是如此。现在我使用firebase作业调度程序来完成它。
class App : Application(){
private val TAG = App::class.java.simpleName
override fun onCreate() {
Log.i("App", "App onCreate")
super.onCreate()
var mAuthListener = FirebaseAuth.AuthStateListener { firebaseAuth ->
val user = firebaseAuth.currentUser
if (user != null) {
Log.i(TAG,"user log in")
try {
val dispatcher2 = FirebaseJobDispatcher(GooglePlayDriver(applicationContext))
val myLocationJob = dispatcher2.newJobBuilder()
.setService(LocationJobService::class.java) // the JobService that will be called
.setTag("my-location-job")
.setLifetime(Lifetime.UNTIL_NEXT_BOOT)
// start between windowStart in sec and windowEnd in seconds from now
.setTrigger(Trigger.executionWindow(0, 60))
.setRecurring(true)//to reschedule job
.setRetryStrategy(RetryStrategy.DEFAULT_EXPONENTIAL)
.setReplaceCurrent(true)
.build()
dispatcher2.mustSchedule(myLocationJob)
Log.i(TAG,"onCreate() started dispatcher " + dispatcher2.toString())
} catch (scheduleFailedException: FirebaseJobDispatcher.ScheduleFailedException) {
Log.i(TAG, "scheduleFailedException " + scheduleFailedException)
}
}else{
Log.i(TAG,"user not log in")
}
}
FirebaseApp.initializeApp(applicationContext)
FirebaseAuth.getInstance().addAuthStateListener(mAuthListener)
}
}
我的服务类应该在期间运行：
class LocationJobService : JobService(),
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
com.google.android.gms.location.LocationListener{
var job : JobParameters? = null
override fun onStartJob(job: JobParameters?): Boolean {
Log.i(TAG,"onStartJob()")
this.job = job
var thread = object : Thread(){
override fun run() {
buildGoogleApiClient()
Log.i(TAG,"run()")
}
}
thread.start()
return true
}
override fun onStopJob(job: JobParameters?): Boolean {
Log.i("TAG", "onStopJob");
return true;
}
private val TAG = LocationJobService::class.java.simpleName
var mLocationRequest: LocationRequest? = null
var mGoogleApiClient: GoogleApiClient? = null
var mLastLocation: Location? = null
var mRequestLocationUpdatesPendingIntent : PendingIntent? = null
fun buildGoogleApiClient() {
synchronized(this) {
Log.i(TAG, "buildGoogleApiClient")
mGoogleApiClient = GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build()
mGoogleApiClient!!.connect()
}
}
private fun createLocationRequest() {
Log.i(TAG, "createLocationRequest")
mLocationRequest = LocationRequest()
mLocationRequest!!.interval = 100
mLocationRequest!!.fastestInterval = 100
mLocationRequest!!.smallestDisplacement = 1F
mLocationRequest!!.priority = LocationRequest.PRIORITY_HIGH_ACCURACY
}
override fun onConnected(p0: Bundle?) {
Log.i(TAG, "onConnected")
createLocationRequest()
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return
}
Log.i(TAG, "start request locationOfUserWhoChangeIt updates ")
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this)
// request locationOfUserWhoChangeIt updates
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient,
mLocationRequest,
mRequestLocationUpdatesPendingIntent)
}
override fun onConnectionSuspended(p0: Int) {
Log.i(TAG, "onConnectionSuspended")
mGoogleApiClient!!.connect()
}
override fun onConnectionFailed(p0: ConnectionResult) {
Log.i(TAG, "onConnectionFailed: google maps" + p0.errorMessage)
}
override fun onLocationChanged(location: Location?) {
if (FirebaseAuth.getInstance().currentUser != null) {
Log.i(TAG, "onLocationChanged")
mLastLocation = location!!
addCurrentUserLocationToFirebase(mLastLocation!!)
}
}
private fun addCurrentUserLocationToFirebase(lastLocation: Location) {
var locations = FirebaseDatabase.getInstance().getReference("Locations")
var currentUser = FirebaseAuth.getInstance().currentUser
if (currentUser != null) {//prevent if user click logout to not update locationOfUserWhoChangeIt
Log.i(TAG, "addCurrentUserMarkerAndRemoveOld() current user: " + currentUser!!.uid + " location " + lastLocation.toString() )
val scoresRef = locations.child(currentUser!!.uid)
scoresRef.keepSynced(true)
val connectedRef = FirebaseDatabase.getInstance().getReference(".info/connected")
connectedRef.addValueEventListener(object : ValueEventListener {
override fun onDataChange(snapshot: DataSnapshot) {
val connected = snapshot.getValue(Boolean::class.java)!!
if (connected) {
Log.i(TAG,"connected")
locations.child(currentUser!!.uid)
.setValue(TrackingModel(currentUser.uid,
currentUser!!.email!!,
lastLocation.latitude.toString(),
lastLocation.longitude.toString()), object : DatabaseReference.CompletionListener {
override fun onComplete(error: DatabaseError?, reference: DatabaseReference?) {
Log.i(TAG,"onComplete()")
if(error == null){
Log.i(TAG,"onComplete() position saved to firebase database")
Log.i(TAG,"okey stop service")
mGoogleApiClient!!.disconnect()
jobFinished(job!!, false) //it must be called here, since I return true
}else{
Log.i(TAG,"there is problem to add data to database")
}
}
})
} else {
Log.i(TAG,"not connected")
}
}
override fun onCancelled(error: DatabaseError) {
System.err.println("Listener was cancelled")
}
})
}
}
override fun onDestroy() {
Log.i(TAG,"destroy")
super.onDestroy()
}
}
我有一个大问题。当我在手机中关闭应用程序时（我向左滑动我的应用程序）。我没有连接到我的firebase数据库。在我的连接监听器中，我得到了not connected。因此，CompletionListener永远不会在我无法连接时运行。当我们关闭应用程序时，我读取了firebase连接已关闭。那么当我的应用程序没有运行时，如何连接到我的firebase数据库以添加我当前的位置？
我知道我可以运行前台服务但在某些设备中它也可以被系统杀死。所以我想在一段时间内安排我的服务，但我不知道如何连接到我的firebase数据库。