介绍

如果让 RecyclerView 实现 1 个网格布局的运行效果，就需要使用 GridLayoutManager 类也就是网格布局管理器。GridLayoutManager 就像 GridView 一样，需要设置网格的列数才可以正常的显示。

例子

RecyclerView的网格布局

编写布局文件

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <!--列表控件-->
    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/recyclerview"
        android:background="#EEEEEE"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical" />

</RelativeLayout>

创建layout_item02.xml?

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical">
    <!--显示图片-->
    <ImageView
        android:id="@+id/icon"
        android:layout_width="100dp"
        android:layout_height="100dp"
        android:layout_gravity="center_horizontal" />
    <!--显示图片的标题-->
    <TextView
        android:id="@+id/title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:textSize="17sp" />
</LinearLayout>

创建GridAdapter.java

public class GridAdapter extends RecyclerView.Adapter<GridAdapter.MyViewHolder> {

    //图标数组
    private int[] icons = {
            R.drawable.img01, R.drawable.img02, R.drawable.img03,
            R.drawable.img04, R.drawable.img05, R.drawable.img06,
            R.drawable.img07, R.drawable.img08, R.drawable.img09,
            R.drawable.img10, R.drawable.img11
    };
    //名字数组，引用资源文件中的文字
    private int[] names = {
            R.string.name1, R.string.name2, R.string.name3,
            R.string.name4, R.string.name5, R.string.name6,
            R.string.name7, R.string.name8, R.string.name9,
            R.string.name10, R.string.name11
    };

    private Context lContext; //上下文
    private List<Integer> listIcon = new ArrayList<Integer>(); //图标集合
    private List<Integer> listName = new ArrayList<Integer>(); //名称集合

    public GridAdapter(Context context) {
        lContext = context;
        //设置菜单行数与行内图标、名称、信息
        for (int i = 0; i < 11; i++) {
            listIcon.add(icons[i]);
            listName.add(names[i]);
        }
    }

    @Override
    public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        //获取列表中每行的布局文件
        View view = LayoutInflater.from(lContext).inflate(R.layout.layout_item02, parent, false);
        MyViewHolder holder = new MyViewHolder(view);
        return holder;
    }

    @Override
    public void onBindViewHolder(MyViewHolder holder, int position) {
        //设置图标
        holder.img.setBackgroundResource(listIcon.get(position));
        //设置名称
        holder.name.setText(listName.get(position));

    }

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

    class MyViewHolder extends RecyclerView.ViewHolder {
        public TextView name; //名字与信息
        public ImageView img; //图标

        //获取相关控件
        public MyViewHolder(View itemView) {
            super(itemView);
            name = (TextView) itemView.findViewById(R.id.name);
            img = (ImageView) itemView.findViewById(R.id.img);
        }
    }
}

编写GridRecyclerActivity

public class GridRecyclerActivity extends AppCompatActivity {

    private RecyclerView gRecyclerView; //列表控件
    private GridAdapter gridAdapter; //适配器

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_grid_recycler);
        gRecyclerView = (RecyclerView) findViewById(R.id.recyclerview);
        //创建网格布局管理器
        GridLayoutManager manager = new GridLayoutManager(this, 2);
        //设置网格列表中第1个与第2个item（子项）跨列每个子项占两个位置
        manager.setSpanSizeLookup(new GridLayoutManager.SpanSizeLookup() {
            @Override
            public int getSpanSize(int position) {
                if (position == 0 ) { //判断是第1个或者第2个子项
                    return 2; //返回要跨的列数
                } else {
                    return 1;
                }
            }
        });
        //设置网格布局管理器
        gRecyclerView.setLayoutManager(manager);
        //设置适配器
        gridAdapter = new GridAdapter(this);
        gRecyclerView.setAdapter(gridAdapter);
    }
}