RecyclerView(二)——双层RecyclerView嵌套

如上图所示，此页面包含两个RecyclerView的嵌套实现，外层为瀑布流布局，里层为线性布局。

1 里层线性布局书籍列表部分

1.1 ChildAdapter

    public class ChildAdapter extends RecyclerView.Adapter<ChildAdapter.ChildViewHolder> {
    private List<String> mBooks;
    private int mLayoutId;

    public ChildAdapter(List<String> list, int layoutId) {
        mBooks = list;
        mLayoutId = layoutId;
    }

    @NonNull
    @Override
    public ChildViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
        View view = LayoutInflater.from(viewGroup.getContext()).inflate(mLayoutId, viewGroup, false);
        return new ChildViewHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull ChildViewHolder childViewHolder, int i) {
        childViewHolder.textView.setText(mBooks.get(i));
    }

    @Override
    public int getItemCount() {
        return mBooks.size();
    }

    static class ChildViewHolder extends RecyclerView.ViewHolder {
        TextView textView;

        public ChildViewHolder(View view) {
            super(view);
            textView = (TextView) view.findViewById(R.id.text_book);
        }
    }
}

1.2 对应的layout

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <TextView
        android:id="@+id/text_book"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />
LinearLayout>

1.3 BookShelf数据对象

  public class BookShelf {

    private String name;
    private List<String> books;

    public void setName(String name) {
        this.name = name;
    }

    public String getName() {
        return name;
    }

    public void setBooks(List<String> books) {
        this.books = books;
    }

    public List<String> getBooks() {
        return books;
    }
}

2 外层瀑布流布局部分代码

2.1 ParentAdapter

在外层RecyclerView的Adapter中绑定里层RecyclerView与ChildAdapter的关系。

public class ParentAdapter extends RecyclerView.Adapter<ParentAdapter.ParentViewHolder> {

    private List<BookShelf> mDatas;
    private int mLayoutId;
    private Context mContext;

    public ParentAdapter(List<BookShelf> bookList, int layoutId, Context context) {
        mDatas = bookList;
        mLayoutId = layoutId;
        mContext = context;
    }

    @NonNull
    @Override
    public ParentViewHolder onCreateViewHolder(@NonNull final ViewGroup viewGroup, final int i) {
        View view = LayoutInflater.from(viewGroup.getContext()).inflate(mLayoutId, viewGroup, false);
        return new ParentViewHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull ParentViewHolder viewHolder, int i) {
        BookShelf bookShelf = mDatas.get(i);
        viewHolder.textView.setText(bookShelf.getName());

        // 子RecyclerView
        LinearLayoutManager manager = new LinearLayoutManager(mContext);
        manager.setOrientation(LinearLayoutManager.VERTICAL);
        viewHolder.recyclerView.setLayoutManager(manager);
        viewHolder.recyclerView.setAdapter(new ChildAdapter(bookShelf.getBooks(), R.layout.layout_item_book));
    }

    @Override
    public int getItemCount() {
        return mDatas.size();
    }

    static class ParentViewHolder extends RecyclerView.ViewHolder {
        TextView textView;
        RecyclerView recyclerView;

        public ParentViewHolder(View view) {
            super(view);
            textView = (TextView) view.findViewById(R.id.text_view);
            recyclerView = (RecyclerView) view.findViewById(R.id.recycler_view_parent);
        }
    }

}

2.2 对应的layout文件

<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:background="#ccffff"
    android:layout_margin="5dp"
    app:cardCornerRadius="5dp">

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <TextView
            android:id="@+id/text_view"
            android:textStyle="bold"
            android:textSize="20sp"
            android:layout_marginTop="10dp"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />

        <android.support.v7.widget.RecyclerView
            android:id="@+id/recycler_view_parent"
            android:layout_marginTop="5dp"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />

    LinearLayout>

android.support.v7.widget.CardView>

2.3 MainActivity

public class MainActivity extends AppCompatActivity {

    private List<BookShelf> mDatas = new ArrayList<>();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        RecyclerView recyclerView = (RecyclerView)findViewById(R.id.recycler_view);

        initData();

        StaggeredGridLayoutManager manager = new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.VERTICAL);
        recyclerView.setLayoutManager(manager);
        ParentAdapter adapter = new ParentAdapter(mDatas, R.layout.layout_staggered_grid_nest_adapter_item, this);
        recyclerView.setAdapter(adapter);
    }

    // 组装数据
    private void initData() {
        mDatas.clear();

        BookShelf bookShelf1 = new BookShelf();
        bookShelf1.setName("科幻类");
        String[] books1 = new String[]{"三体", "流浪地球", "降临"};
        bookShelf1.setBooks(Arrays.asList(books1));
        mDatas.add(bookShelf1);

        BookShelf bookShelf2 = new BookShelf();
        bookShelf2.setName("政治类");
        String[] books2 = new String[]{"美国陷阱", "从赫鲁晓夫到普京", "为什么是以色列", "南京大屠杀"};
        bookShelf2.setBooks(Arrays.asList(books2));
        mDatas.add(bookShelf2);

        BookShelf bookShelf3 = new BookShelf();
        bookShelf3.setName("文学类");
        String[] books3 = new String[]{"我们仨", "小姨多鹤", "我与地坛", "黄金时代", "雪国"};
        bookShelf3.setBooks(Arrays.asList(books3));
        mDatas.add(bookShelf3);

        BookShelf bookShelf4 = new BookShelf();
        bookShelf4.setName("医学类");
        String[] books4 = new String[]{"只有医生知道", "基因传", "癌症传"};
        bookShelf4.setBooks(Arrays.asList(books4));
        mDatas.add(bookShelf4);

        BookShelf bookShelf5 = new BookShelf();
        bookShelf5.setName("财经类");
        String[] books5 = new String[]{"小狗钱钱", "激荡四十年", "巴菲特和他的财富人生"};
        bookShelf5.setBooks(Arrays.asList(books5));
        mDatas.add(bookShelf5);

        BookShelf bookShelf6 = new BookShelf();
        bookShelf6.setName("悬疑类");
        String[] books6 = new String[]{"白夜行", "东方列车谋杀案", "心理罪"};
        bookShelf6.setBooks(Arrays.asList(books6));
        mDatas.add(bookShelf6);

        BookShelf bookShelf7 = new BookShelf();
        bookShelf7.setName("技术类");
        String[] books7 = new String[]{"android进阶之光", "Kotlin实战", "黑客与画家", "程序是怎样跑起来的"};
        bookShelf7.setBooks(Arrays.asList(books7));
        mDatas.add(bookShelf7);
    }
}

2.4 activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#ccffff"
    tools:context=".MainActivity">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/recycler_view"
        android:clipToPadding="false"
        android:paddingBottom="50dp"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

RelativeLayout>

3 demo下载

可在这里下载双层RecyclerView嵌套实现的demo