隨着 Google 推出了全新的設計語言 Material Design,還迎來了新的 Android 支持庫 v7,其中就包含了 Material Design 設計語言中關於 Card 卡片概念的實現 —— CardView。RecyclerView也是谷歌V7包下新增的控件,用來替代ListView的使用,在RecyclerView標準化了ViewHolder相似於ListView中convertView用來作視圖緩存.android
RecyclerView的優勢就是,他能夠經過設置LayoutManager來快速實現listview、gridview、瀑布流的效果,並且還能夠設置橫向和縱向顯示,添加動畫效果等。git
CardView實現卡片化效果。github
下拉加載使用SwipeRefreshLayout,是官方的下拉刷新控件,簡潔美觀的風格使其普遍應用在項目中。美中不足的是SwipeRefreshLayout缺乏上拉加載的效果,今天結合RecyclerView實現一個支持下拉刷新與上拉加載的SwipeRefreshLayout。緩存
案例包含了:RecyclerView基本使用,RecyclerView上拉刷新下拉加載,RecyclerView多Item佈局,CardView基本使用和CardView上拉刷新下拉加載。如圖:(注:第三個案例線顯示格式在模擬器上有問題,手機則沒問題的,手機測試效果更佳)dom
佈局:ide
<android.support.v7.widget.RecyclerView android:id="@+id/my_recycler_view" android:scrollbars="vertical" android:layout_width="match_parent" android:layout_height="match_parent"/>
Activity:佈局
public class RecyclerViewActivity extends Activity { private RecyclerView recyclerView; private List<String> mDatas; private RecyclerAdapter1 adapter; @SuppressLint("InlinedApi") @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.demo1); initData(); initView(); } private void initView() { recyclerView=(RecyclerView) findViewById(R.id.demo1_recycler); // 設置佈局管理LayoutManager LinearLayoutManager manager=new LinearLayoutManager(this); //設置水平或者垂直 // manager.setOrientation(LinearLayoutManager.HORIZONTAL); recyclerView.setLayoutManager(manager); // (可選)若是能夠肯定每一個item的高度是固定的,設置這個選項能夠提升性能 recyclerView.setHasFixedSize(true); adapter=new RecyclerAdapter1(this,mDatas); recyclerView.setAdapter(adapter); adapter.setOnItemClickListener(new IOnClickListenter() { @Override public void onItemClick(View view, int position) { Toast.makeText(getApplicationContext(),position+"---"+mDatas.get(position),Toast.LENGTH_LONG).show(); } }); } private void initData() { mDatas = new ArrayList<String>(); for (int i = 0; i <= 50; i++) { mDatas.add("item---" +i); } } }
Adapter:post
public class RecyclerAdapter1 extends RecyclerView.Adapter<RecyclerAdapter1.ViewHolder>{ private Context context; private List<String> list; public RecyclerAdapter1(Context context, List<String> list){ this.context=context; this.list=list; } @Override public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { View view= LayoutInflater.from(context).inflate(R.layout.demo1_item,parent,false); ViewHolder viewHolder=new ViewHolder(view); return viewHolder; } @Override public void onBindViewHolder(ViewHolder holder, int position) { holder.textView.setText(list.get(position)); } @Override public int getItemCount() { return list.size(); } private IOnClickListenter onClickListenter=null; public void setOnItemClickListener(IOnClickListenter listener) { this.onClickListenter=listener; } public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener{ private TextView textView; public ViewHolder(View view) { super(view); textView=(TextView)view.findViewById(R.id.textview1); textView.setOnClickListener(this); } @Override public void onClick(View v) { if (onClickListenter != null) { onClickListenter.onItemClick(v,getPosition()); } } } }
上拉刷新下拉加載佈局性能
<android.support.v4.widget.SwipeRefreshLayout android:id="@+id/swipeRefreshLayout" android:layout_width="match_parent" android:layout_height="match_parent"> <android.support.v7.widget.RecyclerView android:id="@+id/recyclerView" android:layout_width="match_parent" android:layout_height="match_parent"> </android.support.v7.widget.RecyclerView> </android.support.v4.widget.SwipeRefreshLayout>
上拉刷新下拉加載Activity測試
public class RecyclerViewPullActivity extends Activity { private SwipeRefreshLayout swipeRefreshLayout; private MyRefreshRecyclerView recyclerView; public static List<String> list=new ArrayList<String>(); private RecyclerAdapter2 adapter; private Handler mHandler = new Handler(); @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.demo2); initView(); } private void initView(){ swipeRefreshLayout = (SwipeRefreshLayout) findViewById(R.id.swipe_layout); recyclerView = (MyRefreshRecyclerView) findViewById(R.id.recycler); adapter=new RecyclerAdapter2(); recyclerView.setLayoutManager(new LinearLayoutManager(getApplicationContext())); swipeRefreshLayout.setColorSchemeResources(R.color.blue,R.color.green); swipeRefreshLayout.post(new Runnable() { @Override public void run() { swipeRefreshLayout.setRefreshing(true); } }); mHandler.postDelayed(new Runnable() { @Override public void run() { getData(); recyclerView.setAdapter(adapter); adapter.notifyDataSetChanged(); swipeRefreshLayout.setRefreshing(false); } },1500); swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() { @Override public void onRefresh() { mHandler.postDelayed(new Runnable() { @Override public void run() { getData(); recyclerView.setAdapter(adapter); adapter.notifyDataSetChanged(); swipeRefreshLayout.setRefreshing(false); } }, 1500); } }); recyclerView.setMyRefreshRecyclerViewListener(new MyRefreshRecyclerView.MyRefreshRecyclerViewListener() { @Override public void onLoadMore() { mHandler.postDelayed(new Runnable() { @Override public void run() { if (list.size() > 14) { recyclerView.setLoadMore(true); } else { int randomInt = new Random().nextInt(100); list.add("上拉加載添加數字:" + randomInt); adapter.notifyDataSetChanged(); recyclerView.setLoadMore(false); } } }, 1000); } }); } private void getData() { list.clear(); Random random = new Random(); while (list.size() < 12) { int randomInt = random.nextInt(100); list.add(String.valueOf(randomInt)); } } }
compile 'com.android.support:recyclerview-v7:23.2.1'
compile 'com.android.support:cardview-v7:23.2.1'