Android RecyclerView简单使用

在android5.0后推出了一个RecyclerView替代ListView和GridView,在性能上也比listview或者gridview更好,由于做TV端开发,所以一直没用上,现在有时间还是要学习下,

RecyclerView实现ListView效果:

package com.simple;
import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import java.util.List;
/**
 * Created by Adminis on 2017/5/7.
 */
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyHolder> {
    private LayoutInflater layoutInflater;
    private Context mContext;
    private List<String> mDatas ;
    public void setmDatas(List<String> list) {
        this.mDatas = list;
    }
    public MyAdapter(Context context) {
        this.mContext = context;
        layoutInflater = LayoutInflater.from(mContext);
    }
    @Override
    public MyHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View root =  layoutInflater.inflate(R.layout.layout_item,null);
        MyHolder holder = new MyHolder(root);
        return holder;
    }
    @Override
    public void onBindViewHolder(MyHolder holder, int position) {
        holder.tv_content.setText(mDatas.get(position));
    }
    @Override
    public int getItemCount() {
        return mDatas!=null?mDatas.size():0;
    }
    class MyHolder extends RecyclerView.ViewHolder {
        private TextView tv_content;
        public MyHolder(View itemView) {
            super(itemView);
            tv_content = (TextView) itemView.findViewById(R.id.tv_content);
        }
    }
}

上面是adapter,你会发现和之前的listview的adapter是有区别的,而且adapter中的几个抽象方法也不一样：

MainActivity.java 调用层:

package com.simple;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends AppCompatActivity {
    private RecyclerView recyclerview;
    private MyAdapter adapter;
    private List<String> datas;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        recyclerview = (RecyclerView) findViewById(R.id.recyclerview);
        initData();
        adapter = new MyAdapter(this);
        adapter.setmDatas(datas);
        recyclerview.setAdapter(adapter);
        recyclerview.setLayoutManager(new LinearLayoutManager(this,LinearLayoutManager.VERTICAL,false));
    }
    private void initData() {
        datas = new ArrayList<>();
        datas.add("刘亦菲");
        datas.add("张含韵");
        datas.add("陈好");
        datas.add("汤唯");
        datas.add("韩雪");
        datas.add("张嘉倪");
        datas.add("姚笛");
        datas.add("张柏芝");
        datas.add("林凤娇");
        datas.add("俞飞鸿");
        datas.add("贾静雯");
        datas.add("周杰伦");
        datas.add("麻吉弟弟");
        datas.add("王艳");
        datas.add("Gameapple");
        datas.add("公交MM");
    }
}

layout_item.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#FFB6C1"
    >
    <TextView
        android:id="@+id/tv_content"
        android:layout_width="match_parent"
        android:layout_height="45dp"
        android:gravity="center"
        />
</RelativeLayout>

效果图:

你会发现RecyclerView并没有分割线,RecyclerView并没有给我们提供什么属性设置分割线，这要自己去实现.

RecyclerView实现GridView效果:

只要把

recyclerview.setLayoutManager(new LinearLayoutManager(this,LinearLayoutManager.VERTICAL,false));

改成:

 recyclerview.setLayoutManager(new GridLayoutManager(this,3));

效果图:

你会发现listview变成gridview切换非常简单,就一行代码的事,这个在展示本地图片的时候,经常有这二种UI展示来回切换,如果用RecyclerView实现非常简单,

如果把

 recyclerview.setLayoutManager(new GridLayoutManager(this,3));

吧GridLayoutManager中的3改为1,就变成了listview

RecyclerView实现Gallery或者HorizontalListView效果:

只要把RecyclerView设置

recyclerview.setLayoutManager(new LinearLayoutManager(this,LinearLayoutManager.HORIZONTAL,false));

效果图:

这个在一些新闻app中的标题可以用这个实现,比如今日头条app标题view就可以这么实现,