CODEWITHSUNDEEP
androidfirebasefirebase-realtime-database
Matthew David Glynn
Matthew David Glynn

Reputation: 21

How do I access a specific value from my Firebase Database?

I followed a Youtube video on accessing a specific value from my database, this is exactly what the video had (except I changed it to my values). When their app ran, it made a toast with the corresponding value(s). When I start mine I get the error "Unfortunately, App has stopped." Am I doing something wrong or am I going about this the wrong way?

protected void onCreate(final Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);


    FirebaseDatabase database = FirebaseDatabase.getInstance();
    test = database.getReference("https://matts-macros.firebaseio.com/values");
    test.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            Map<String, String> data = (Map<String, String>) dataSnapshot.getValue();
            Toast.makeText(getApplicationContext(), "Value: + " + data.get("adjustedcarbs"), Toast.LENGTH_LONG).show();
        }

        @Override
        public void onCancelled(DatabaseError databaseError) {

        }
    });
}

database values

Upvotes: 1

Views: 51

Answers (1)

Levi Moreira
Levi Moreira

Reputation: 11995

You're accessing the reference in a wrong way. See the docs. You should do one of two things:

1) Replace this:

test = database.getReference("https://matts-macros.firebaseio.com/values");

with this:

test = database.getReference().child("values");

2) If you want to use your url, you should do this instead:

String myUrl = "https://matts-macros.firebaseio.com/values";
test = FirebaseDatabase.getInstance().getReferenceFromUrl(myUrl);

Regarding your parsing error, try with a Map<String,Object> :

Map<String, Object> data = (Map<String, Object>) dataSnapshot.getValue();

Upvotes: 2

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