Android Firebase retrieve data from child node

Question

I\'m trying to get the data from Firebase child node. But it throws Can\'t convert object of type java.lang.String to type uk.co.stableweb.geethika.model.DailyVerse

Answer 1

By this method

mRef.addChildEventListener(childEventListener);

you subscribe for

.child("daily_verse");

children. daily_verse has two children: verse_content and verse_title. The type of these children is String. So, you get two String datasnapshot in the onChildAdd listener.

Update: Try something like this:

mRef = FirebaseDatabase.getInstance().getReference();
mRef.keepSynced(true);

ChildEventListener childEventListener = new ChildEventListener() {
    @Override
    public void onChildAdded(DataSnapshot dataSnapshot, String previousChildName) {
        Log.d("Child Event,Verse", dataSnapshot.getKey());
        if ("daily_verse".equal(dataSnapshot().getKey){
            dailyVerse = dataSnapshot.getValue(DailyVerse.class);
            Log.d("TEST","Object: "+dailyVerse);
            if (dailyVerse!=null){
               Log.d("TEST","values: "+dailyVerse.verse_title+", "+dailyVerse.verse_content);
            }
        }

    }

    @Override
    public void onChildChanged(DataSnapshot dataSnapshot, String previousChildName) {
        Log.d("Child Event,Verse", "onChildChanged:" + dataSnapshot.getKey());
        if ("daily_verse".equal(dataSnapshot().getKey){
          dailyVerse = dataSnapshot.getValue(DailyVerse.class);
          Log.d("TEST","Changed object: "+dailyVerse);
          if (dailyVerse!=null){
             Log.d("TEST","Changed values: "+dailyVerse.verse_title+", "+dailyVerse.verse_content);
          }
        }
    }

    @Override
    public void onChildRemoved(DataSnapshot dataSnapshot) {

    }

    @Override
    public void onChildMoved(DataSnapshot dataSnapshot, String previousChildName) {

    }

    @Override
    public void onCancelled(DatabaseError databaseError) {
        Log.w("Firebase", "onCancelled", databaseError.toException());
        Toast.makeText(context, "Failed to load verse",
                Toast.LENGTH_SHORT).show();
    }
};

mRef.addChildEventListener(childEventListener);

You should subscribe to events from parent object and check the key at events listener.