从节点

Question

Picture of my firebase database

如何从 user1 （帖子）节点<检索 值 < / em>和将添加到 listview ？

我在下面尝试了这段代码，但我不知道下一步该怎么做

FirebaseDatabase.getInstance()
.getReference("user1")
.child("posts")
.addValueEventListener(

 );

Answer 1

要解决此问题，请使用以下代码：

DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference postsRef = rootRef.child("users").child("user1").child("posts");
ValueEventListener eventListener = new ValueEventListener() {
    @Override
    public void onDataChange(DataSnapshot dataSnapshot) {
        List<String> list = new ArrayList<>();
        for(DataSnapshot ds : dataSnapshot.getChildren()) {
            String title = ds.child("title").getValue(String.class);
            String body = ds.child("body").getValue(String.class);
            list.add(title + " / " +  body);
            Log.d("TAG", title + " / " +  body);
        }
        ListView listView = (ListView) findViewById(R.id.list_view);
        ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(getActivity(), android.R.layout.simple_list_item_1, list);
        listView.setAdapter(arrayAdapter);
    }

    @Override
    public void onCancelled(DatabaseError databaseError) {}
};
postsRef .addListenerForSingleValueEvent(eventListener);

将显示的数据是：

Xxxx / Xxxxxxxxxxxxxx
Xxxxx / Xxxxxxxxxx