RecyclerView 使用方法

1. gradle依赖

compile 'com.android.support:recyclerview-v7:26.1.0'

2. 主页面布局
   acticity_main.xml

3. 页面中每一项的布局
   fruit_item.xml

4. 为RecyclerView准备一个适配器，新建FruitAdapter类，让这个适配器继承自RecyclerView.Adapter,并将泛型指定为FruitAdapter.ViewHolder,其中ViewHolder是FruitAdapter中的一个内部类。

package com.example.bbw.recyclerview;

import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;

import java.util.List;

/**
 * Created by bbw on 2017/11/6.
 * @author bbw
 */

public class FruitAdapter extends RecyclerView.Adapter{

    private List mFruitList;

    static class ViewHolder extends RecyclerView.ViewHolder{

        ImageView fruitImage;
        TextView fruitName;
        View fruitView;

        public ViewHolder(View itemView) {
            super(itemView);
            fruitView = itemView;
            fruitImage = itemView.findViewById(R.id.fruitImage);
            fruitName = itemView.findViewById(R.id.fruitName);
        }
    }

    public FruitAdapter(List fruitList){
        mFruitList = fruitList;
    }

    @Override
    public FruitAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.fruit_item,parent,false);
        final ViewHolder holder = new ViewHolder(view);
        //点击时候
        holder.fruitView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                int position = holder.getAdapterPosition();
                Fruit fruit = mFruitList.get(position);
                Toast.makeText(v.getContext(),fruit.getName(),Toast.LENGTH_SHORT).show();
            }
        });
        holder.fruitImage.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                int position = holder.getAdapterPosition();
                Fruit fruit = mFruitList.get(position);
                Toast.makeText(v.getContext(),fruit.getName(),Toast.LENGTH_SHORT).show();
            }
        });
        return holder;
    }

    @Override
    public void onBindViewHolder(FruitAdapter.ViewHolder holder, int position) {

        Fruit fruit = mFruitList.get(position);
        holder.fruitImage.setImageResource(fruit.getImageId());
        holder.fruitName.setText(fruit.getName());
    }

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

这里首先定义一个内部类ViewHolder,继承自RecycylerView.ViewHolder。然后ViewHolder的构造函数中要传入一个view参数，这个参数就是RecyclerView子项的最外层布局，现在就可以通过findViewById()来获取布局中的ImageView和TextView。之后就是重写三个方法。

5. MainActivity.java

package com.example.bbw.recyclerview;

import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.StaggeredGridLayoutManager;
import android.widget.LinearLayout;

import java.util.ArrayList;
import java.util.List;

/**
 * recyclerView知识点
 * @author bbw
 */
public class MainActivity extends AppCompatActivity {

    private List fruitList = new ArrayList<>();

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //初始化水果数据
        initFruits();
        RecyclerView mRecyclerView = findViewById(R.id.recycler_view);
        //线性布局
//        LinearLayoutManager mLinearLayoutManager = new LinearLayoutManager(this);
//        mLinearLayoutManager.setOrientation(LinearLayoutManager.HORIZONTAL);
//        mRecyclerView.setLayoutManager(mLinearLayoutManager);
        //瀑布流布局
        StaggeredGridLayoutManager layoutManager = new StaggeredGridLayoutManager(3,StaggeredGridLayoutManager.VERTICAL);
        mRecyclerView.setLayoutManager(layoutManager);
        FruitAdapter adapter = new FruitAdapter(fruitList);
        mRecyclerView.setAdapter(adapter);
    }

    private void initFruits() {

        for (int i=0; i<2; i++){

            Fruit apple = new Fruit("Apple",R.drawable.apple_pic);
            fruitList.add(apple);
            Fruit banana = new Fruit("Banana",R.drawable.banana_pic);
            fruitList.add(banana);
            Fruit orange = new Fruit("Orange",R.drawable.orange_pic);
            fruitList.add(orange);
            Fruit watermelon = new Fruit("Watermelon",R.drawable.watermelon_pic);
            fruitList.add(watermelon);
            Fruit pear = new Fruit("Pear",R.drawable.pear_pic);
            fruitList.add(pear);
            Fruit grape = new Fruit("Grape",R.drawable.grape_pic);
            fruitList.add(grape);
            Fruit pineapple = new Fruit("Pineapple",R.drawable.pineapple_pic);
            fruitList.add(pineapple);
            Fruit strawberry = new Fruit("Strawberry",R.drawable.strawberry_pic);
            fruitList.add(strawberry);
            Fruit cherry = new Fruit("Cherry",R.drawable.cherry_pic);
            fruitList.add(cherry);
            Fruit mango = new Fruit("Mango",R.drawable.mango_pic);
            fruitList.add(mango);
        }
    }
}