如何在实时数据库 Anroid Java 中获取数据推送的位置？

Question

我有这样的 JSON 树结构

SampleData 
 -sampleEmail
   -Push key // Generated by .push() in realtime database
     "data1" : "Sample Data 1"
     "data2" : "Sample Data 2"
     "data3" : "Sample Data 3"
   -Push key // Generated by .push() in realtime database
     "data1" : "Sample Data 1"
     "data2" : "Sample Data 2"
     "data3" : "Sample Data 3"

firebase 是否有方法来获取像 (0, 1, 2,...) 这样的按键位置我正在使用 RecyclerViewAdapter，我想比较持有者位置和数据库中的位置以获取特定项目。 有办法吗？

Answer 1

在这里，你可以看到你的答案。 我评论了你需要的那部分，你可以检查这个代码片段：

    FirebaseRecyclerOptions<ModelClass> options =
            new FirebaseRecyclerOptions.Builder<QuizSetMode> ()
                    .setQuery ( FirebaseRef (SampleData/SampleEmail), ModelClass.class )
                    .build ();


    FirebaseRecyclerAdapter<ModelClass,ViewHolder> adapter =
            new FirebaseRecyclerAdapter<ModelClass, ViewHolder>(options) {
                @Override
                protected void onBindViewHolder(@NonNull final StudentViewHolder2 holder, final int position, @NonNull final ModelClass model) {

                    String listPostKey = getRef(position).getKey();
                    // This is your Desired answer (listPostKey)
                    // Here You can Get all the push key in (listPostKey)
                    // You Can Perform any operation here using listPostKey



                }

                @NonNull
                @Override
                public StudentViewHolder2 onCreateViewHolder(@NonNull ViewGroup viewGroup, int viewType) {
                    View view  = LayoutInflater.from ( viewGroup.getContext () ).inflate ( R.layout.quiz_topics,viewGroup,false );
                    StudentViewHolder2 viewHolder  = new StudentViewHolder2(  view);
                    return viewHolder;

                }

                @Override
                public void onDataChanged() {
                    super.onDataChanged();

                    recyclerView.setVisibility(View.VISIBLE);
                    progressDialog.dismiss();


                }


            };