很简单为RecyclerView添加头部：使用一个类RecyclerViewHeader

首先看下自己的RecyclerView是否包裹在 LinearLayout, FrameLayout, RelativeLayout.这三种布局中，否则会报错：

 Currently, NOT already aligned RecyclerViewHeader can only be used for RecyclerView with a parent of one of types: LinearLayout, FrameLayout, RelativeLayout.

意思就是说RecyclerViewHeader这个东西只使用在线性布局、帧布局、相对布局包裹下的RecyclerView

例如：

activity_main布局

<LinearLayout   

    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"    android:layout_height="match_parent">    <android.support.v7.widget.RecyclerView        android:id="@+id/recyclerview"        android:layout_width="match_parent"        android:layout_height="match_parent" />

</LinearLayout>

检查好上面的步骤之后，开始RecyclerViewHeader

1、首先在model层的build的dependencies中加入依赖：compile 'com.bartoszlipinski.recyclerviewheader:library:1.2.0'

dependencies {    compile 'com.bartoszlipinski.recyclerviewheader:library:1.2.0'}

为你的header创建一个XML布局文件：（就是你要加的头部的布局，我这里只加了一个TextView），这是一个单独的xml文件

1、创建一个布局文件

<?xml version="1.0" encoding="utf-8"?><FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="100dp">    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_gravity="center"        android:text="header" /></FrameLayout>

2、MainActivity代码

public class MainActivity extends AppCompatActivity implements MyRecyclerViewAdapter.onItemClickListener {
    //声明RecyclerView    private RecyclerView mRecyclerview;    //数据源    private List<String> list;
    //声明Adapter    MyRecyclerViewAdapter myRecyclerViewAdapter;
    //声明RecyclerViewHeader对象    RecyclerViewHeader header;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);
        //初始化RecyclerViewHeader        header = RecyclerViewHeader.fromXml(this, R.layout.header);
        mRecyclerview = (RecyclerView) findViewById(R.id.recyclerview);                list = new ArrayList<>();        for (int i = 0; i < 100; i++) {            list.add("这是第" + i + "条");        }        myRecyclerViewAdapter = new MyRecyclerViewAdapter(list);
//使用RecyclerView一定要setLayoutManager        mRecyclerview.setLayoutManager(new LinearLayoutManager(this));
//        mRecyclerview.setLayoutManager(new GridLayoutManager(this,2));//        mRecyclerview.setLayoutManager(new StaggeredGridLayoutManager(3,StaggeredGridLayoutManager.HORIZONTAL));
        //把RecyclerViewHeader赋予RecyclerView,这个一定要写在setLayoutManager之后
header.attachTo(mRecyclerview);        mRecyclerview.setAdapter(myRecyclerViewAdapter);        myRecyclerViewAdapter.setOnItemClickListener(this);            }    @Override    public void onItemClick(View view, int position) {        Log.d("TAG", "类名==MainActivity" + "方法名==onItemClick===:" + "当前点击的是第" + position);    }}
目前该库RecyclerViewHeader适用于LinearLayoutManager,GridLayoutManager和StaggeredGridLayoutManager布局的RecyclerView。