什么是RecyclerView
關于RecyclerView，是一個主要用于展示和回收View的有一個控件，在官用了一句話來概括
RecyclerView 是一種通過提供有限的數據項窗口有效顯示大數據集的視圖。
基提供幾個基本的功能，
控制其顯示的方式 ———>LayoutManager—(必需)
控制Item間的間隔 ———>ItemDecoration—-(非必需)
控制Item增刪的動畫——->ItemAnimator——(非必需)
以上就可以完成ListView大部的功能了，但是確缺少了一個很常用的功能，就是Item的點需事件。當然，這個并不是什么問題，上文也說了，RecyclerView是一個用于控制view展示的回收的，其它的都由用戶去定制。給了用戶當的自由度。下面來看一些基本的使方式。
基本使用
由于RecyclerView并不是在Android的基本庫中，所以如果開發者需要使用RecyclerView里，需要gradle引用對應的擴展包，
compile 'com.android.support:recyclerview-v7:25.0.1'
這后實大家需要做的和使用ListView差別也不大，只需要調置LayoutManager和Adapter就可以完成最基礎的顯示了。Adapter及Adapter需要的ViewHolder均繼承自RecyvlerView的內部類。
RecyclerView的Adapter
public class DemoAdapter extends RecyclerView.Adapter<DemoViewHolder> { private List<String> data; public DemoAdapter(List<String> data) { this.data = data; } @Override public DemoViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { DemoViewHolder holder = new DemoViewHolder(LayoutInflater.from( parent.getContext()).inflate(R.layout.demo_recycler_view_item, parent, false)); return holder; } @Override public void onBindViewHolder(DemoViewHolder holder, int position) { holder.getView().setText(data.get(position)); } @Override public int getItemCount() { return data.size(); }}RecyclerView的ViewHolder
public class DemoViewHolder extends RecyclerView.ViewHolder { private TextView view; public DemoViewHolder(View itemView) { super(itemView); view = (TextView) itemView.findViewById(R.id.item_view); } public TextView getView() { return view; }}項目主Activity
public class RecyclerViewDemoActivity extends AppCompatActivity { private RecyclerView recyclerView; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_recycler_view_demo); recyclerView = (RecyclerView) findViewById(R.id.recycler_view); String[] datas = {"1", "2", "3", "4", "5", "6", "7", "8", "9", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "0"}; List<String> strings = Arrays.asList(datas); DemoAdapter adapter = new DemoAdapter(strings); recyclerView.setLayoutManager(new LinearLayoutManager(this)); recyclerView.setAdapter(adapter); }}activity layout文件布局
<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:id="@+id/activity_recycler_view_demo" android:layout_width="match_parent" android:layout_height="match_parent" tools:context="com.yjeeq.study.recyclerview.RecyclerViewDemoActivity"> <android.support.v7.widget.RecyclerView android:id="@+id/recycler_view" android:layout_width="match_parent" android:layout_height="match_parent"> </android.support.v7.widget.RecyclerView></RelativeLayout>
item layout文件布局
<?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="40dp" android:orientation="vertical"> <TextView android:id="@+id/item_view" android:layout_width="match_parent" android:layout_height="match_parent" android:background="@android:color/holo_blue_dark" android:gravity="center" /></LinearLayout>
以下是運行效果
設置單擊事件
上面已經完成基本的展示，這里就介紹一下怎么為Recycler加上點擊事件。其實思路很簡單，就是在RecyclerView上的addOnItemTouchListener上做文章。這里給出具體實現。相信大家一看就懂。
* OnItemTouchListener的實現*
public class RecyclerItemClickListener implements RecyclerView.OnItemTouchListener { private View childView; private RecyclerView touchView; public RecyclerItemClickListener(Context context, final OnItemClickListener mListener) { mGestureDetector = new GestureDetector(context, new GestureDetector.SimpleOnGestureListener() { @Override public boolean onSingleTapUp(MotionEvent ev) { if (childView != null && mListener != null) { mListener.onItemClick(childView, touchView.getChildPosition(childView)); } return true; } @Override public void onLongPress(MotionEvent ev) { if (childView != null && mListener != null) { mListener.onLongClick(childView, touchView.getChildAdapterPosition(childView)); } } }); } GestureDetector mGestureDetector; public interface OnItemClickListener { public void onItemClick(View view, int position); public void onLongClick(View view, int posotion); } @Override public boolean onInterceptTouchEvent(RecyclerView recyclerView, MotionEvent motionEvent) { mGestureDetector.onTouchEvent(motionEvent); childView = recyclerView.findChildViewUnder(motionEvent.getX(), motionEvent.getY()); touchView = recyclerView; return false; } @Override public void onTouchEvent(RecyclerView recyclerView, MotionEvent motionEvent) { } @Override public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) { }} 使用方式
首先在主類繼承 RecyclerItemClickListener.OnItemClickListener，之后在主類中添加如下方法。
private void setOnItemClick() { recyclerView.addOnItemTouchListener(new RecyclerItemClickListener(this, this)); } public void onItemClick(View view, int position) { Log.d("XXXXXX", "onItemClick : postion " + position); } @Override public void onLongClick(View view, int posotion) { Log.d("XXXXXX", "onLongClick position : " + posotion); }以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持VEVB武林網。
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