我有一项服务，可以在计时器停止时替换停车位的状态，但它仅在我的应用程序运行时有效。我想让我的服务替换槽的状态，即使我的应用已关闭。我已经阅读了有关startForeground的信息，但是我找不到有关如何正确使用它的明确答案。这是我的代码：
定时器服务：
public class TimerService extends Service {
private Vibrator v;
private static final int uniqueID = 71399;
//databae declarations
private DrawerLayout nDrawerLayout; // variable for DrawerLayout
private ActionBarDrawerToggle nToggle;// variable for toggle button
private FirebaseAuth firebaseAuth;//instance of Firebase
private FirebaseAuth.AuthStateListener authStateListener;
FirebaseDatabase database;
DatabaseReference myRef;//database reference
NotificationCompat.Builder notification;
@Nullable
@Override
public IBinder onBind(Intent intent) {
return null;
}
@Override
public void onCreate() {
super.onCreate();
notification = new NotificationCompat.Builder(this);
notification.setAutoCancel(false);
}
//starts warning timer
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
SharedPreferences sharedPreferences = getSharedPreferences("Reservation", Context.MODE_PRIVATE);
String slot = sharedPreferences.getString("slot","");
Toast.makeText(this,"service slot:"+slot,Toast.LENGTH_LONG).show();
WarningTimer();
DurationTimer(slot);
return START_STICKY;
}
//1 hour warning timer
public void WarningTimer(){
final long dur = 40000;
CountDownTimer countDownTimer = new CountDownTimer(dur,1000) {
@Override
public void onTick(long millisUntilFinished) {
}
@Override
public void onFinish() {
long n[] = {1,1000,500,1000,500,1000,500,1000,500,1000};
v = (Vibrator) getSystemService(Context.VIBRATOR_SERVICE);
v.vibrate(n, -1);
halfnotif();
}
};
countDownTimer.start();
}
//full duration timer
public void DurationTimer(final String slot){
final long dur2 = 60000;
CountDownTimer countDownTimer = new CountDownTimer(dur2,1000) {
@Override
public void onTick(long millisUntilFinished) {
long millis= millisUntilFinished;
String hms= String.format("%02d:%02d:%02d",
TimeUnit.MILLISECONDS.toHours(millis),
TimeUnit.MILLISECONDS.toMinutes(millis) - TimeUnit.HOURS.toMinutes(TimeUnit.MILLISECONDS.toHours(millis))
//seconds
,TimeUnit.MILLISECONDS.toSeconds(millis) - TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(millis))
);
}
@Override
public void onFinish() {
long n[] = {1,1000,500,1000,500,1000,500,1000,500,1000};
v = (Vibrator) getSystemService(Context.VIBRATOR_SERVICE);
v.vibrate(n, -1);
//lagay code ng firebase here
DatabaseReference myRef = FirebaseDatabase.getInstance().getReference().child("parking_lot");
myRef.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
for (DataSnapshot ds : dataSnapshot.getChildren()) {
final String key = ds.getKey();
//final String[] Car_Slots = {"slot1","slot2","slot3","slot4","slot5","slot6","slot7","slot8","slot9","slot10",
//"slot11","slot12","slot13","slot14","slot15","slot16","slot17","slot18","slot19","slot20","slot21","slot22"};
DatabaseReference keyReference = FirebaseDatabase.getInstance().getReference().child("parking_lot").child(key);
keyReference.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
String value = dataSnapshot.child("status").getValue(String.class);
if (key.equals(slot)) {
if (value.equals("occupied")) {
//Toast.makeText(TimerService.this,"occupied (service)"+slot,Toast.LENGTH_LONG).show();onDestroy();
} else if (value.equals("reserved")) {
//Toast.makeText(TimerService.this,"reserved (service)"+slot,Toast.LENGTH_LONG).show();
database = FirebaseDatabase.getInstance();
final DatabaseReference myRef = database.getReference("parking_lot");
final DatabaseReference myRef1 = myRef.child(slot);
final DatabaseReference myRef2 = myRef1.child("status");
myRef2.setValue("vacant");
} else if (value.equals("vacant")) {
//Toast.makeText(TimerService.this,"vacant (service)"+slot,Toast.LENGTH_LONG).show();
}
}
Log.d(TAG, "Read ok");
}
@Override
public void onCancelled(DatabaseError databaseError) {
Log.d(TAG, "Read failed");
}
});
}
}
@Override
public void onCancelled(DatabaseError databaseError) {
Log.d(TAG, "Read failed");
}
});
endnotif();
}
};
countDownTimer.start();
}
@Override
public void onDestroy() {
stopSelf();
super.onDestroy();
}
//kalahati
public void halfnotif(){
notification.setSmallIcon(R.drawable.ic_info_black_24dp);
notification.setContentText("1 Hour remaining!");
notification.setTicker("leave the parking lot!");
notification.setWhen(System.currentTimeMillis());
notification.setContentTitle("TICK TOCK");
//NotificationCompat.Builder builder = notification.setContentText("Apps are now unblocked!");
ClickNotif();
}
//Notify the user that the timer has ended
public void endnotif(){
notification.setSmallIcon(R.drawable.ic_directions_car_black_24dp);
notification.setContentText("00:00");
notification.setTicker("leave the parking lot!");
notification.setWhen(System.currentTimeMillis());
notification.setContentTitle("Times Up!");
//NotificationCompat.Builder builder = notification.setContentText("Apps are now unblocked!");
ClickNotif();
}
//other parts of notif
public void ClickNotif(){
Intent intent1 = new Intent(this, Parking.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent1, PendingIntent.FLAG_UPDATE_CURRENT);
notification.setContentIntent(pendingIntent);
NotificationManager nm = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
nm.notify(uniqueID, notification.build());
onDestroy();
}
}
任何帮助将不胜感激
要在应用关闭的情况下更改槽位的状态，我建议您在 Cloud Functions for Firebase 中编写一个函数来为您执行此更改。
为此，我建议您从这篇文章中看到道格的答案。