Android 从firebase检索用户ID下的数据

我面临一个如何检索UID下所有数据以列出字符串的问题。但我不知道如何传递UID

编辑

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我想检索所有数据。我的意思是可能有许多uid及其子uid。我想访问所有uid（不仅是我的uid，还有mdg节点下的其他uid）。在

活动中创建一个全局
ArrayList

private ArrayList<User> arrayList = new ArrayList<>();

    DatabaseReference reference = FirebaseDatabase.getInstance().getReference().child("msg");

    reference.addListenerForSingleValueEvent(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            for (DataSnapshot snapshotMessages : dataSnapshot.getChildren()) {
                for (DataSnapshot snapshot : snapshotMessages.getChildren()) {

                    String post_text = snapshot.child("post_text").getValue(String.class);
                    String upload_time = snapshot.child("upload_time").getValue(String.class);
                    String uploader_name = snapshot.child("uploader_name").getValue(String.class);

                    User user = new User(post_text, upload_time, uploader_name);

                    arrayList.add(user);

                }
            }
        }

        @Override
        public void onCancelled(DatabaseError databaseError) {

        }
    });

然后在您的
活动中

private ArrayList<User> arrayList = new ArrayList<>();

    DatabaseReference reference = FirebaseDatabase.getInstance().getReference().child("msg");

    reference.addListenerForSingleValueEvent(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            for (DataSnapshot snapshotMessages : dataSnapshot.getChildren()) {
                for (DataSnapshot snapshot : snapshotMessages.getChildren()) {

                    String post_text = snapshot.child("post_text").getValue(String.class);
                    String upload_time = snapshot.child("upload_time").getValue(String.class);
                    String uploader_name = snapshot.child("uploader_name").getValue(String.class);

                    User user = new User(post_text, upload_time, uploader_name);

                    arrayList.add(user);

                }
            }
        }

        @Override
        public void onCancelled(DatabaseError databaseError) {

        }
    });

我想检索所有数据。我的意思是可以有许多uid及其子项。我想访问所有uid（不仅是ny uid，还包括mdg节点下的其他uid）。更新的代码。它现在将获取所有数据。有希望地