How to read data from Firebase Database?

I'm making a game, if the player wins, then the victory is added to the database. How can I read the data from here?

and paste here:

I read the player's name in a different way, which cannot be repeated with victories and defeats.

CodePudding user response：

To be able to read the data under the jjjj node, please use the following lines of code:

DatabaseReference db = FirebaseDatabase.getInstance().getReference();
DatabaseReference nameRef = db.child("players").child("jjjj");
nameRef.get().addOnCompleteListener(new OnCompleteListener<DataSnapshot>() {
    @Override
    public void onComplete(@NonNull Task<DataSnapshot> task) {
        if (task.isSuccessful()) {
            DataSnapshot snapshot = task.getResult();
            String loses = snapshot.child("loses").getValue(Long.class);
            String name = snapshot.child("name").getValue(String.class);
            String wins = snapshot.child("wins").getValue(Long.class);
            Log.d("TAG", loses   "/"   name   "/"   wins);
        } else {
            Log.d("TAG", task.getException().getMessage()); //Never ignore potential errors!
        }
    }
});

The result in the logcat will be:

3/jjjj/4

Things to notice:

Always create a reference that points to the node that you want to read.
If your database is located in another lcoation than the default, check this answer out.

CodePudding user response：

use this method

This is the method of fetching data from the firebase realtime database

DatabaseReference reference = FirebaseDatabase.getInstance().getReference();

    reference.child("players").child(name).addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(@NonNull DataSnapshot snapshot) {
            for (DataSnapshot dataSnapshot : snapshot.getChildren()){

            }
        }

        @Override
        public void onCancelled(@NonNull DatabaseError error) {

        }
    });