Krishna Kumar Krishna Kumar - 11 months ago 71
Android Question

retieving data from firebase dynamically in android

I have my database structured like this in firebase:-

app root:
some data
some data
some data

and so on. I want to retrieve the data from this database. Only some specific data and display it in the app. Also I want download all the images(stored in the firebase storage) from the link provided in helper, and display them in app.

I have tried the documentation for retrieving the data but was unable to retrieve a specific list of data.


private DatabaseReference myDb;
myDb = FirebaseDatabase.getInstance().getReference();

final String userId = getUid();
new ValueEventListener() {

public void onDataChange(DataSnapshot dataSnapshot) {

User uData = dataSnapshot.getValue(User.class);


This is what I learnt from documentation and was doing, it was good for a single valued data but I want to retrieve all the data under user category or helper.

  1. How do I iterate through all the data?

  2. How do I display a downloaded image from a link into an android app?

I hope it helps now.

Answer Source

Iterate over a list of Firebase nodes using dataSnapshot.getChildren() (should return an iterable irrc).


   new ValueEventListener() {
       public void onDataChange(DataSnapshot dataSnapshot) {
           for (DataSnapshot childSnapshot : datasSnapshot.getChildren() {
               User uData = childSnapshot.getvalue(User.class);

       // onCancelled()...

You display images in Android using ImageViews. I would recommend checking out the Square's Picasso Android image library for some useful functionality.