Android 为Recyclerview添加滚动监听事件，以及为它每一个item设置点击监听事件

虽然recyclerview为 整个recyclerview设置了一些监听事件，但是没有自带为其中的item设置点击事件

本文将提供一种recyclerview中item的点击监听事件的实现方法
先看看效果图：

第一，你需要一个接口：

public interface OnItemClickListener {        void OnItemclick(View view,int position);}

第二，再适配器中 声明一个该接口的引用

public class Adapter extends RecyclerView.Adapter<ViewHolderr> {    private LayoutInflater layoutInflater;    private Context context;    private String[] datas;    private OnItemClickListener onItemClickListener;//声明一个接口的引用    public Adapter(Context context, String[] datas) {//构造函数传入Context对象和数据源        this.layoutInflater=LayoutInflater.from(context);        this.context = context;        this.datas = datas;    }    @Override    public ViewHolderr onCreateViewHolder(ViewGroup parent, int viewType) {        View view=layoutInflater.inflate(R.layout.item,parent,false);        ViewHolderr viewHolderr=new ViewHolderr(view);        return viewHolderr;    }    @Override    public void onBindViewHolder(final ViewHolderr holder, int position) {        holder.getButton().setText(datas[position]);        //在该函数中为recyclerview的视图绑定监听事件        if (onItemClickListener != null) {            holder.getButton().setOnClickListener(new View.OnClickListener() {                @Override                public void onClick(View view) {                  onItemClickListener.OnItemclick(holder.itemView, holder.getLayoutPosition());                }            });        }    }    @Override    public int getItemCount() {        return datas.length;    }    public  void setOnItemClickListner(OnItemClickListener onItemClickListner){        this.onItemClickListener=onItemClickListner;    }}

第三，就是在Mainactivity中给recyclerview设置监听事件了：

protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        ButterKnife.bind(this);        final LinearLayoutManager linearLayoutManager=new LinearLayoutManager(this,LinearLayoutManager.VERTICAL,false);        recyclerview.setLayoutManager(linearLayoutManager);        Adapter adapterr=new Adapter(this,datas);        adapterr.setOnItemClickListner(new OnItemClickListener() {            @Override            public void OnItemclick(View view, int position) {                Toast.makeText(MainActivity.this,  datas[position], Toast.LENGTH_SHORT).show();            }        });        recyclerview.setAdapter(adapterr);        recyclerview.setHasFixedSize(true);        recyclerview.setItemAnimator(new DefaultItemAnimator());    }

以下是对整个recycler的监听事件（来自https://developer.android.com/）

 recyclerview.addOnScrollListener(new RecyclerView.OnScrollListener() {            //返回当前recyclerview的可见的item数目，也就是datas.length            //dx是水平滚动的距离，dy是垂直滚动距离，向上滚动的时候为正，向下滚动的时候为负            @Override            public void onScrolled(RecyclerView recyclerView, int dx, int dy) {                super.onScrolled(recyclerView, dx, dy);                int firstVisibleItemPosition=linearLayoutManager.findFirstVisibleItemPosition();//可见范围内的第一项的位置                int lastVisibleItemPosition=linearLayoutManager.findLastVisibleItemPosition();//可见范围内的最后一项的位置                int itemCount=linearLayoutManager.getItemCount();//recyclerview中的item的所有的数目                //System.out.println(linearLayoutManager.getItemCount());                System.err.println(dy);            }        });        recyclerview.addOnScrollListener(new RecyclerView.OnScrollListener() {            @Override            public void onScrollStateChanged(RecyclerView recyclerView, int newState) {                super.onScrollStateChanged(recyclerView, newState);                /*                new State                0（SCROLL_STATE_IDLE）表示recyclerview是不动的（The RecyclerView is not currently scrolling.）                1（SCROLL_STATE_DRAGGING）表示recyclerview正在被拖拽（The RecyclerView is currently being dragged by outside input such as user touch input.）                2（SCROLL_STATE_SETTLING）表示recyclerview正在惯性下滚动（The RecyclerView is currently animating to a final position while not under outside control.）                 */                switch(newState)                {                    case 0:                        System.out.println("recyclerview已经停止滚动");                        break;                    case 1:                        System.out.println("recyclerview正在被拖拽");                        break;                    case 2:                        System.out.println("recyclerview正在依靠惯性滚动");                        break;                }            }        });

Demo源码已经上传到github.com,需要的朋友请戳https://github.com/Gpwner/Recyclerview/tree/master