我正在尝试添加一些日期在滚动顶部在一个回收器视图。这是工作，除了滚动，当一些新数据被添加时，它搞砸了一切。

我看到了这个主题：

链接1

链接2

但是他们都没有解决我的问题。

也许有人能帮我…

我使用volley获得一些数据，如下所示：

try {
                //Getting json
                json = array.getJSONObject(i);

                //Adding data to the object
                PostObj.setImageUrl(json.getString(Config.TAG_PPIC));
                ...


            } catch (JSONException e) {
                e.printStackTrace();
            }
            //Adding object to the list
            listLf.add(0, PostObj); //0, postobj
        }

        //Notifying the adapter that data has been added or changed
        //adapter.notifyDataSetChanged(); the scroll will jump to position 0
        adapter.notifyItemRangeChanged(0, adapter.getItemCount()); // still not working
    }

我试图添加Adapter. NonofyItemRangeChanged（0，Adapter.getItemCount（））；但仍然是同样的事情。

我也试过：

// Save state
private Parcelable recyclerViewState;
recyclerViewState = recyclerView.getLayoutManager().onSaveInstanceState();

// Restore state
recyclerView.getLayoutManager().onRestoreInstanceState(recyclerViewState);

它也不起作用。也许我把它放错了地方什么的…

我想要一些建议，我做错了什么，我如何获得新数据，通知适配器而不弄乱滚动位置？

编辑---------------------------------- 全班：

public class Comments extends BaseActivity {


    private List<LfGetSet> listLf;

    //Creating Views
    private RecyclerView recyclerView;
    private RecyclerView.LayoutManager layoutManager;
    private RecyclerView.Adapter adapter;

    //Volley Request Queue
    private RequestQueue requestQueue;
    private String requestCount = "0";
    private String lastrequestCount = "0";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        ViewGroup content = (ViewGroup) findViewById(R.id.content_frame);
        getLayoutInflater().inflate(R.layout.activity_comments, content, true);

        //Initializing Views
        recyclerView = (RecyclerView) findViewById(R.id.recyclerViewLf);
        recyclerView.setHasFixedSize(true);
        //layoutManager = new LinearLayoutManager(this);

        final LinearLayoutManager layoutManager = new LinearLayoutManager(this);
        layoutManager.setStackFromEnd(true);

        recyclerView.setLayoutManager(layoutManager);

        //Initializing our list
        listLf = new ArrayList<>();
        requestQueue = Volley.newRequestQueue(this);

        //Calling method to get data to fetch data
        getData();

        recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
            @Override
            public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
                super.onScrolled(recyclerView, dx, dy);
                if (isLastItemDisplaying(recyclerView)) {
                    getData();
                }
            }
        });

        //initializing our adapter
        adapter = new LfAdapter(listLf, this);

        //Adding adapter to recyclerview
        recyclerView.setAdapter(adapter);


    }

    private JsonArrayRequest getDataFromServer(String requestCount) {
        ...
        return jsonArrayRequest;
    }

    //This method will get data from the web api
    private void getData() {
        //Adding the method to the queue by calling the method getDataFromServer
        requestQueue.add(getDataFromServer(requestCount));
        lastrequestCount = requestCount;
        //Incrementing the request counter
        requestCount++;
    }

    //This method will parse json data
    private void parseData(JSONArray array) {
        for (int i = 0; i < array.length(); i++) {
            //Creating the object
            LfGetSet PostObj = new LfGetSet();
            JSONObject json = null;
            try {
                //Getting json
                json = array.getJSONObject(i);

                //Adding data to the object
                PostObj.setImageUrl(json.getString(Config.TAG_PPIC));
                ...


            } catch (JSONException e) {
                e.printStackTrace();
            }
            //Adding object to the list
            listLf.add(0, PostObj); //0, postobj
        }

        //Notifying the adapter that data has been added or changed
        adapter.notifyDataSetChanged();
    }

    //This method would check that the recyclerview scroll has reached the bottom or not
    private boolean isLastItemDisplaying(RecyclerView recyclerView) {
        if (recyclerView.getAdapter().getItemCount() != 0) {
            int lastVisibleItemPosition = ((LinearLayoutManager) recyclerView.getLayoutManager()).findFirstVisibleItemPosition();
            if (lastVisibleItemPosition != RecyclerView.NO_POSITION
                    && lastVisibleItemPosition == 1
                    && lastrequestCount != requestCount
                    && requestCount != "0")
                return true;
        }
        return false;
    }

}