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androidtimereal-time

Get time from online

Is there any way to get time from online for my android app. I wanna create an android app where I need to use time which are not effected by changing device time. So I wanna get current time from online or firebase database.

Solution

  • If you don't care for millisecond accuracy, and if you are already using google firebase or don't mind using it (they provide a free tier), check this out: https://firebase.google.com/docs/database/android/offline-capabilities#clock-skew

    Basically, firebase database has a field that provides offset value between the device time and the firebase server time. You can use this offset to get the current time.

    DatabaseReference offsetRef = 
FirebaseDatabase.getInstance().getReference(".info/serverTimeOffset");
offsetRef.addValueEventListener(new ValueEventListener() {
  @Override
  public void onDataChange(DataSnapshot snapshot) {
    double offset = snapshot.getValue(Double.class);
    double estimatedServerTimeMs = System.currentTimeMillis() + offset;
  }

  @Override
  public void onCancelled(DatabaseError error) {
    System.err.println("Listener was cancelled");
  }
});