Header的布局文件

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适配器

public class HeaderAdapterextends RecyclerView.Adapter {

private ListstatusList;

private ViewmHeaderView;

// 首先定义几个常量标记item的类型

    public static final int ITEM_TYPE_HEADER =0;

public static final int ITEM_TYPE_CONTENT =1;

public HeaderAdapter(List statusList) {

this.statusList = statusList;

}

@Override

    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent,int viewType) {

if(mHeaderView !=null && viewType ==ITEM_TYPE_HEADER)return new Holder(mHeaderView);

View layout = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_recyclerview, parent,false);

return new Holder(layout);

}

@Override

    public void onBindViewHolder(RecyclerView.ViewHolder holder,int position) {

if (getItemViewType(position)==0)return;

int pos = getRealPosition(holder);

String data =statusList.get(pos).getData();

int id =statusList.get(pos).getId();

if(holderinstanceof Holder) {

((Holder) holder).item_data.setText(data);

((Holder) holder).item_id.setText(id+"");

}

}

@Override

    public int getItemCount() {

return mHeaderView ==null ?statusList.size() :statusList.size() +1;

}

@Override

    public int getItemViewType(int position) {

if(mHeaderView ==null)return ITEM_TYPE_CONTENT;

if(position ==0)return ITEM_TYPE_HEADER;

return ITEM_TYPE_CONTENT;

}

public void setHeaderView(View headerView) {

mHeaderView = headerView;

notifyItemInserted(0);

}

public int getRealPosition(RecyclerView.ViewHolder holder) {

int position = holder.getLayoutPosition();

return mHeaderView ==null ? position : position -1;

}

class Holderextends RecyclerView.ViewHolder{

private  TextViewitem_data;

private  TextViewitem_id;

public Holder(View itemView) {

super(itemView);

if (itemView==mHeaderView)return;

item_id = itemView.findViewById(R.id.item_id);

item_data = itemView.findViewById(R.id.item_data);

}

}

}

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Activity中使用

public class MainActivityextends AppCompatActivity {

private RecyclerViewmRecyclerView;

private Listdatas;

private HomeAdapteradapter;

private HeaderAdapterheaderAdapter;

@Override

    protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

//初始化控件

        mRecyclerView = findViewById(R.id.mRecyclerView);

//数据源

        List strings = initData(30);

//设置适配器

        LinearLayoutManager manager=new LinearLayoutManager(this);

mRecyclerView.setLayoutManager(manager);

headerAdapter=new HeaderAdapter(strings);

setHeader(mRecyclerView);

mRecyclerView.setAdapter(headerAdapter);

}

private void setHeader(RecyclerView view) {

View header = LayoutInflater.from(this).inflate(R.layout.item_header, view,false);

headerAdapter.setHeaderView(header);

}

private List initData(int count){

datas=new ArrayList<>();

for (int i=0;i

String s="item"+i;

Status status=new Status();

status.setData(s);

status.setId(i);

datas.add(status);

}

return datas;

}

}

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效果