Android Firebase simply get one child object s data

Question

I have been looking for a way to get one child object s data in Android Firebase   I have found things like Firebase retrieve child Android  All the solutions are suggesting using a  ChildEventListener   however I need to get this data at this moment  not when it is moved  deleted  updated  etcetera   My data is kept in https    firebaseio com users  creation as a string  I figure there must be some simple way to access that without needing to do too much  because if I copy the exact URL to my browser  I can see the   creation   2015 05 31 21 33 55   right there in my  Firebase Forge Dashboard     How can I access this without a listener

User · Accepted Answer

Firebase listeners fire for both the initial data and any changes   If you re looking to synchronize the data in a collection  use ChildEventListener  If you re looking to synchronize a single object  use ValueEventListener  Note that in both cases you re not  getting  the data  You re synchronizing it  which means that the callback may be invoked multiple times  for the initial data and whenever the data gets updated   This is covered in Firebase s quickstart guide for Android  The relevant code and quote   FirebaseRef child  message   addValueEventListener new ValueEventListener        Override   public void onDataChange DataSnapshot snapshot        System out println snapshot getValue        prints  Do you have data  You ll love Firebase          Override   public void onCancelled DatabaseError databaseError                         In the example above  the value event will fire once for the initial state of the data  and then again every time the value of that data changes     Please spend a few moments to go through that quick start  It shouldn t take more than 15 minutes and it will save you from a lot of head scratching and questions  The Firebase Android Guide is probably a good next destination  for this question specifically  https   firebase google com docs database android read-and-write

User · Answer

just fetch specific node data and its working perfect for me  mFirebaseInstance getReference  yourNodeName   getRef   addValueEventListener new ValueEventListener          Override     public void onDataChange DataSnapshot dataSnapshot              for  DataSnapshot postSnapshot   dataSnapshot getChildren                  Log e TAG            postSnapshot child  email   getValue                 Log e TAG            postSnapshot child  name   getValue                           Override     public void onCancelled DatabaseError error               Failed to read value         Log e TAG   Failed to read app title value    error toException

User · Answer

You don t directly read a value  You can set it with  setValue    but there is no  getValue   on the reference object   You have to use a listener  If you just want to read the value once  you use ref addListenerForSingleValueEvent     Example   Firebase ref   new Firebase  YOUR-URL-HERE PATH TO YOUR STUFF    ref addListenerForSingleValueEvent new ValueEventListener         Override    public void onDataChange DataSnapshot dataSnapshot           String value    String  dataSnapshot getValue               do your stuff here with value            Override    public void onCancelled FirebaseError firebaseError                Source  https   www firebase com docs android guide retrieving-data html section-reading-once

User · Answer

I store my data this way   accountsTable - gt    key1 - gt  account1   key2 - gt  account2   in order to get object data   accountsDb   mDatabase child  accountsTable     accountsDb child  some   key   addListenerForSingleValueEvent new ValueEventListener                      Override                 public void onDataChange DataSnapshot snapshot                         try                           Account account    snapshot getChildren   iterator   next                                      getValue Account class                           catch  Throwable e                            MyLogger error this   onCreate eror   e                                                            Override public void onCancelled DatabaseError error

[android] Android Firebase, simply get one child object's data

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