DEMO工程文件下载

链接：https://pan.baidu.com/s/1IgeTZwW3kD0dOmGElIQ5OQ 

提取码：k7qd 

主函数是一个TCPClient，连接电脑server做测试，电脑发送clear则 mItemBeanLists.clear(); 如果电脑发送数据，则按照；符号行分割显示出来。

问题在于，如果我getItemCount里面返回超出mItemBeanLists真实长度的话，会导致clear或remove并刷新后显示的数据并没有真正清除！

MainActivity

public class MainActivity extends Activity {
    private static final String TAG = "MainActivity";

    RecyclerView        recyclerView;
    List<String>        mItemBeanLists   = new ArrayList<>();
    LongListViewAdapter mListViewAdapter = new LongListViewAdapter();

    PZHelp_TCPClient mTCPClient;

    Handler mHandler = new Handler();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        initRecyclerView();

        mTCPClient = new PZHelp_TCPClient("192.168.0.161", 9999, new PZHelp_TCPClient.ReceiveListener() {
            @Override
            public void onSuccess() {
            }

            @Override
            public void onFail(String err) {
            }

            @Override
            public void Receive(String response) {
                Log.d(TAG, "Receive: " + response);
                if (response.equals("clear")) {
                    mItemBeanLists.clear();
                } else {
                    String[] datas = response.split(";", -1);
                    for (int i = 0; i < datas.length; i++) {
                        mItemBeanLists.add(i, datas[i]);
                    }
                }

                mHandler.post(new Runnable() {
                    @Override
                    public void run() {
                        mListViewAdapter.notifyDataSetChanged();
                        for (int i = 0; i < mItemBeanLists.size(); i++) {
                            Log.d(TAG, " mItemBeanLists.get(i): " + mItemBeanLists.get(i));
                        }
                    }
                });
            }
        });
        mTCPClient.start();
    }

    private void initRecyclerView() {
        recyclerView = findViewById(R.id.recyclerView);
        //设置布局管理器
        LinearLayoutManager mLinearLayoutManager1 = new LinearLayoutManager(this);
        mLinearLayoutManager1.setOrientation(LinearLayoutManager.VERTICAL);
        recyclerView.setLayoutManager(mLinearLayoutManager1);
        //设置适配器
        mListViewAdapter.setData(mItemBeanLists);
        recyclerView.setAdapter(mListViewAdapter);
    }

    @Override
    protected void onDestroy() {
        mTCPClient.close();
        super.onDestroy();
    }
}

LongListViewAdapter

public class LongListViewAdapter extends RecyclerView.Adapter<LongListViewAdapter.InnerHolder> {
    String TAG = "LongListViewAdapter";

    private List<String> mData;

    void setData(List<String> data) {
        mData = data;
    }

    @NonNull
    @Override
    public LongListViewAdapter.InnerHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        //创建条目的回调函数
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_recyclerview, parent, false);
        return new LongListViewAdapter.InnerHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull LongListViewAdapter.InnerHolder holder, int position) {
        //绑定数据
        if (mData != null && mData.size() > 0) {
            int nowPosition = position % mData.size();
            holder.setData(mData.get(nowPosition), position);
        }
    }

    @Override
    public int getItemCount() {
        //设置条目数量
        if (mData != null) {
            return Integer.MAX_VALUE;//做循环效果
            //return  mData.size();
        }
        return 0;
    }

    @SuppressLint("SetTextI18n,StaticFieldLeak")
    static class InnerHolder extends RecyclerView.ViewHolder {
        TextView textView;
        int      mPosition;

        InnerHolder(@NonNull View itemView) {
            super(itemView);
            textView = itemView.findViewById(R.id.textView);
        }

        void setData(String s, int position) {
            textView.setText(s);

            mPosition = position;
        }
    }
}

当我第一次发送数据后：

显示的数据正常无误

当我使用clear后：

就可以发现数据并没有完全清除，但实际上mItemBeanLists的的确确情况了,这里的显示我无法理解

再次clear便会“正常”（其实并没有，它是按照一定数量减少的，只是第二次再clear后减少的条目大于剩余的条目）

增加项1：当我返回数值固定为7，每次clear减少前2行，如果返回固定为8，每次clear减少前3行，当我固定为5后，clear直接“失效”，显示的数据不变！