Firebase 如何在按键下检索数据

Question

I can't figure out how to retrieve my data without variable under the push key, so please help.

    reference = FirebaseDatabase.getInstance().getReference("FireAlarm");
    reference.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
            for (DataSnapshot keySnapshot : dataSnapshot.getChildren()){
                dataBaru = keySnapshot.getKey();
                data.setText(dataBaru);
            }
        }

Answer 1

When you are using the following line of code:

dataBaru = keySnapshot.getKey();

You are getting only those pushed keys. If you want to get the values corresponding to the keys, please use the following line of code:

dataBaru = keySnapshot.getValue(String.class);

One more thing, when looping through a DataSnapshot object using getChildren() method, you're most likely getting more than one result so you can simply set it to a TextView . So probably you should use a ListView for that or even better a RecyclerView .