Recycler Android开发

<?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="match_parent"
    android:orientation="vertical">

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

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".recyclerView"
    tools:ignore="MissingDefaultResource">

    <TextView
        android:id="@+id/tv"
        android:textSize="30sp"
        android:layout_width="match_parent"
        android:layout_height="match_parent"></TextView>

</androidx.constraintlayout.widget.ConstraintLayout>

public class MainActivity extends AppCompatActivity {

    // 定义一个Java Bean的List集合
    private List<Bean> data = new ArrayList<>();

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

        // 创建数据，未来给适配器使用
        for (int i = 9990; i < 10100; i++) {
            Bean bean = new Bean();
            bean.setName("张三" + i);
            data.add(bean);
        }
        // 获取RecyclerView的布局对象
        RecyclerView recyclerView = findViewById(R.id.rv);
        // 需要自定义布局才可以使用 如：LinearLayoutManager、网格GridLayoutManager、瀑布流StaggeredGridLayoutManager
        // LinearLayoutManager viewManager = new LinearLayoutManager(this);
        // GridLayoutManager viewManager = new GridLayoutManager(this,3);
        StaggeredGridLayoutManager viewManager = new StaggeredGridLayoutManager(3, LinearLayout.VERTICAL);
        // 布局对象绑定自定义布局（不绑定就没有外观，且控制台报错）
        recyclerView.setLayoutManager(viewManager);
        // 创建适配器对象，以渲染数据
        MyAdapter myAdapter = new MyAdapter(data, this);
        // 布局对象绑定适配器，以便于渲染视图了
        recyclerView.setAdapter(myAdapter);
        // 适配器绑定自定义的单击回调（需要在适配器内部自己创建方法！）
        myAdapter.setRecycleItemClickListener(new MyAdapter.OnRecyClerItemClickListener() {
            @Override
            public void onRecyClerItemClick(int positon) {
                Log.e("自定义回调","点击了："+positon);
            }
        });

    }
}

import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;

import java.util.List;

// 自定义适配器需要继承RecyclerView.Adapter的，且强制我们创建内部类MyViewHolder，防止我们遗忘导致不停的findViewById
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {

    // 数据集合
    private List<Bean> list;
    private Context context;

    // 适配器的构造方法，并传入相应的参数
    public MyAdapter(List<Bean> list, Context context) {
        this.list = list;
        this.context = context;
    }


    @NonNull
    @Override
    public MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        // 获取布局
        View view = View.inflate(context, R.layout.activity_recycler_view, null);
        return new MyViewHolder(view);
    }

    // 绑定数据
    @Override
    public void onBindViewHolder(@NonNull MyViewHolder holder, int position) {
        holder.tv.setText(list.get(position).getName());
    }

    // 获取数据数量
    @Override
    public int getItemCount() {
        return list == null ? 0 : list.size();
    }

    private OnRecyClerItemClickListener mOnItemClickListener;


    // 继承自己的内部类，防止我们遗忘导致不停的findViewById
    public class MyViewHolder extends RecyclerView.ViewHolder {
        private TextView tv;

        public MyViewHolder(@NonNull View itemView) {
            super(itemView);
            tv = itemView.findViewById(R.id.tv);
            itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    if (v != null) {
                        mOnItemClickListener.onRecyClerItemClick(getAdapterPosition());
                    }
                }
            });
        }
    }

    // 设定监听事件
    public void setRecycleItemClickListener(OnRecyClerItemClickListener listener) {
        mOnItemClickListener = listener;
    }

    // 定义本类接口，使得本类拥有自定义功能，需要在调用适配器时，绑定时间才可用
    public interface OnRecyClerItemClickListener {
        void onRecyClerItemClick(int positon);
    }

}