实现一个recycler view实例

下面是一个简单的RecyclerView实例，其中包含一个列表视图，该视图显示一些文本项。

MainActivity.java

public class MainActivity extends AppCompatActivity {

    private RecyclerView mRecyclerView;
    private RecyclerView.Adapter mAdapter;
    private RecyclerView.LayoutManager mLayoutManager;

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

        mRecyclerView = (RecyclerView) findViewById(R.id.recycler_view);
        mRecyclerView.setHasFixedSize(true);

        mLayoutManager = new LinearLayoutManager(this);
        mRecyclerView.setLayoutManager(mLayoutManager);

        String[] myDataset = {"Item 1", "Item 2", "Item 3"};
        mAdapter = new MyAdapter(myDataset);
        mRecyclerView.setAdapter(mAdapter);
    }
}

MyAdapter.java

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
    private String[] mDataset;

    public static class ViewHolder extends RecyclerView.ViewHolder {
        public TextView mTextView;

        public ViewHolder(View v) {
            super(v);
            mTextView = (TextView) v.findViewById(R.id.text_view);
        }
    }

    public MyAdapter(String[] myDataset) {
        mDataset = myDataset;
    }

    @Override
    public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.list_item, parent, false);

        ViewHolder vh = new ViewHolder(v);
        return vh;
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        holder.mTextView.setText(mDataset[position]);
    }

    @Override
    public int getItemCount() {
        return mDataset.length;
    }
}

activity_main.xml

<androidx.recyclerview.widget.RecyclerView
    android:id="@+id/recycler_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

list_item.xml

<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/text_view"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="16dp"
    android:textAppearance="?android:attr/textAppearanceListItem" />

这个RecyclerView实例使用了一个LinearLayoutManager和一个MyAdapter。MyAdapter通过ViewHolder来管理每个列表项的视图。在onCreateViewHolder()方法中，我们使用LayoutInflater将list_item.xml布局文件转换为一个View对象，然后将其传递给ViewHolder。在onBindViewHolder()方法中，我们将mDataset中对应位置的文本设置为ViewHolder中的mTextView中的文本。最后，在MainActivity的onCreate()方法中，我们创建一个LayoutManager和一个Adapter，并将Adapter设置为RecyclerView的适配器。