RecyclerView的使用

RecyclerView在android5.0之后被引进，可以通过导入support-v7对其进行使用。 该控件用于在有限的窗口中展示大量数据集。提供了一种插拔式的体验，高度的解耦，异常的灵活，通过LayoutManager，ItemDecoration , ItemAnimator可以实现多样的效果。

实例一：

public class RecyclerActivity01 extends AppCompatActivity {
    private RecyclerView mRecyclerView;
    private List<String> mDatas;
    private BasicAdapter baseAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_recycler01);
        mRecyclerView = (RecyclerView) findViewById(R.id.rv);
        initData();

        baseAdapter = new BasicAdapter(mDatas, RecyclerActivity01.this);
        mRecyclerView.setAdapter(baseAdapter);
        //声明布局管理器，设置最终的展示效果
        LinearLayoutManager manager = new LinearLayoutManager(this, LinearLayout.VERTICAL, false);
        mRecyclerView.setLayoutManager(manager);

        //设置增加条目的动画
        mRecyclerView.setItemAnimator(new DefaultItemAnimator());

        baseAdapter.setOnItemClickListener(new BasicAdapter.OnItemClickListener() {
            @Override
            public void onItemClick(View itemView, int position) {
                Toast.makeText(RecyclerActivity01.this,"你点击了："+mDatas.get(position),Toast.LENGTH_SHORT).show();
            }

            @Override
            public void onLongItemClick(View itemView, int position) {

            }
        });
    }

    private void initData() {
        mDatas = new ArrayList<>();
        for (int i = 0; i < 48; i++) {
            mDatas.add("第" + i + "条数据");
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.main, menu);
        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case R.id.add:
                baseAdapter.addData(1);
                break;
            case R.id.delete:
                baseAdapter.removeData(1);
                break;
            case R.id.diplay_lv:
                LinearLayoutManager manger = new LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false);
                mRecyclerView.setLayoutManager(manger);
                break;
            case R.id.diplay_gv:
                //第二个参数：定义列数
                GridLayoutManager manager = new GridLayoutManager(this, 3);
                mRecyclerView.setLayoutManager(manager);
                break;
            case R.id.diplay_hlv:
                StaggeredGridLayoutManager sManager = new StaggeredGridLayoutManager(1, StaggeredGridLayoutManager.HORIZONTAL);
                mRecyclerView.setLayoutManager(sManager);
                break;
            case R.id.diplay_hgv:
                sManager = new StaggeredGridLayoutManager(5, StaggeredGridLayoutManager.HORIZONTAL);
                mRecyclerView.setLayoutManager(sManager);
                break;
            case R.id.diplay_staggered:
                Intent intent = new Intent(this, StaggeredActivity.class);
                startActivity(intent);
                break;
        }
        return super.onOptionsItemSelected(item);
    }
}

<android.support.v7.widget.RecyclerView
        android:id="@+id/rv"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

public class BasicAdapter extends RecyclerView.Adapter<BasicAdapter.BasicViewHolder> {
    private List<String> mdatas;
    private Context context;
    private OnItemClickListener listener;

    public BasicAdapter(List<String> mdatas, Context context) {
        this.mdatas = mdatas;
        this.context = context;
    }

    /**
     * des:添加监听
     */
    public void setOnItemClickListener(OnItemClickListener listener) {
        this.listener = listener;
    }
    public interface OnItemClickListener {
         void onItemClick(View itemView, int position);
         void onLongItemClick(View itemView, int position);
    }

    @Override
    public BasicViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

        View view = LayoutInflater.from(context).inflate(R.layout.item_recycler01, parent, false);
        BasicViewHolder holder = new BasicViewHolder(view);
        return holder;
    }

    public void addData(int pos) {
        mdatas.add(pos, "add_data");
        notifyItemInserted(pos);
    }

    public void removeData(int pos) {
        mdatas.remove(pos);
        notifyItemRemoved(pos);
    }

    @Override
    public void onBindViewHolder(BasicViewHolder holder, int position) {
        holder.tv.setText(mdatas.get(position));
        setUpEvent(holder);
    }

    protected void setUpEvent(final BasicViewHolder holder) {
        if (listener != null) {
            holder.itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    int position = holder.getLayoutPosition();
                    listener.onItemClick(holder.itemView, position);
                }
            });

            holder.itemView.setOnLongClickListener(new View.OnLongClickListener() {
                @Override
                public boolean onLongClick(View v) {
                    int position = holder.getLayoutPosition();
                    listener.onLongItemClick(holder.itemView, position);
                    return false;
                }
            });
        }
    }

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

    class BasicViewHolder extends RecyclerView.ViewHolder {
        TextView tv;
        public BasicViewHolder(View itemView) {
            super(itemView);
            tv = (TextView) itemView.findViewById(R.id.id_tv1);
        }
    }
}

效果图：

实例二：实现照片墙，宽度一定，高度不确定

public class PhoneWallActivity extends AppCompatActivity {
    private RecyclerView phrv;
    private PhoneWalladapter walladapter;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_phone_wall);
        phrv = (RecyclerView) findViewById(R.id.pwrv);
        walladapter = new PhoneWalladapter(this);

        phrv.setAdapter(walladapter);
        StaggeredGridLayoutManager manager = new StaggeredGridLayoutManager(2
                ,StaggeredGridLayoutManager.VERTICAL);
        phrv.setLayoutManager(manager);

    }
}

<android.support.v7.widget.RecyclerView
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:id="@+id/pwrv"/>

public class PhoneWalladapter extends RecyclerView.Adapter<PhoneWalladapter.PhotoViewHolder> {
private Context context;
    private String imgUrls[];
    private List<Integer>mHeight;

    public PhoneWalladapter(Context context) {
        this.context = context;
        imgUrls = ImageUrls.imageurls;
        mHeight = new ArrayList<>();
        for (int i = 0; i < imgUrls.length; i++) {
            mHeight.add((int)(300+Math.random()*400));
        }
    }


    @Override
    public PhotoViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View itemView = LayoutInflater.from(context).inflate(R.layout.item_phone,parent,false);
        PhotoViewHolder holder = new PhotoViewHolder(itemView);
        return holder;
    }

    @Override
    public void onBindViewHolder(PhotoViewHolder holder, int position) {

        ViewGroup.LayoutParams lp = holder.iv.getLayoutParams();
        lp.height = mHeight.get(position);
        holder.iv.setLayoutParams(lp);

        ImageOptions options = new ImageOptions.Builder().setFailureDrawableId(R.mipmap.ic_launcher)
                .setLoadingDrawableId(R.mipmap.ic_launcher).build();
        x.image().bind(holder.iv,imgUrls[position],options);
    }

    @Override
    public int getItemCount() {
        return imgUrls.length;
    }

    class PhotoViewHolder extends RecyclerView.ViewHolder{
        ImageView iv;
        public PhotoViewHolder(View itemView) {
            super(itemView);
            iv = (ImageView)itemView.findViewById(R.id.item_iv);
        }
    }
}

效果图：

实例三：实现下载刷新上拉加载效果：

public class RecyclerActivity04 extends AppCompatActivity {

    private RecyclerView mRecyclerView;
    private SwipeRefreshLayout swipeRefreshLayout;
    
    private List<Map<String,String>>mDatas;
    private LinearLayoutManager manager;
    private RecyclerAdapter4 adapter;
    private Handler handler = new Handler();

    private boolean isLoading = false;    //设置是否处于上啦加载状态
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_recycler04);
        initView();
        setEvent();
    }
    private void initView(){
        mRecyclerView = (RecyclerView) findViewById(R.id.id_rv);
        swipeRefreshLayout = (SwipeRefreshLayout) findViewById(R.id.srl);
        swipeRefreshLayout.setColorSchemeColors(Color.RED,Color.GREEN);
        manager = new LinearLayoutManager(this,LinearLayoutManager.VERTICAL,false);
        mRecyclerView.setLayoutManager(manager);
        mDatas = new ArrayList<>();
        getData();
        adapter = new RecyclerAdapter4(this,mDatas);
        mRecyclerView.setAdapter(adapter);
    }

    private void setEvent(){
        //设置下拉刷新的操作
        swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
            @Override
            public void onRefresh() {
                handler.postDelayed(new Runnable() {
                    @Override
                    public void run() {
                        mDatas.clear();
                        getData();
                        adapter.notifyDataSetChanged();
                        swipeRefreshLayout.setRefreshing(false);
                    }
                },3000);
            }
        });
        //设置上啦加载的监听器
        mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
            @Override
            public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
                super.onScrollStateChanged(recyclerView, newState);
            }

            @Override
            public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
                super.onScrolled(recyclerView, dx, dy);
                //获得可见条目最后一条的位置
                int lastVisibleItemPosition = manager.findLastVisibleItemPosition();
                if (lastVisibleItemPosition+1==adapter.getItemCount()){
                    //获取是否在下拉刷新
                    boolean isRefresh = swipeRefreshLayout.isRefreshing();
                    if (isRefresh){
                        return;
                    }

                    if (!isLoading){
                        isLoading = true;
                         //没有处于加载状态，然后需要加载数据，就可以分页加载了
                        handler.postDelayed(new Runnable() {
                            @Override
                            public void run() {
                                getData();
                                adapter.notifyDataSetChanged();
                                adapter.notifyItemRemoved(adapter.getItemCount());
                                isLoading = false;
                            }
                        },4000);
                    }
                }
            }
        });
    }
    /**
     * 加载数据
     * */
    private void getData(){
        int size = mDatas.size();
        for (int i = 0; i <20 ; i++) {
            Map<String,String>map = new HashMap<>();
            map.put("title","title======"+(i+size));
            map.put("summary","summary--------"+(i+size));
            mDatas.add(map);
        }
    }
}

<android.support.v4.widget.SwipeRefreshLayout
        android:id="@+id/srl"
        android:layout_height="match_parent"
        android:layout_width="match_parent">
        <android.support.v7.widget.RecyclerView
            android:id="@+id/id_rv"
            android:layout_height="match_parent"
            android:layout_width="match_parent">

        </android.support.v7.widget.RecyclerView>
    </android.support.v4.widget.SwipeRefreshLayout>

public class RecyclerAdapter4 extends RecyclerView.Adapter<RecyclerView.ViewHolder>{
    private Context context;
    private List<Map<String,String>>mDatas;
    private final int TYPE_COMMON = 0;
    private final int TYPE_FOOTER = 1;

    public RecyclerAdapter4(Context context, List<Map<String, String>> mDatas) {
        this.context = context;
        this.mDatas = mDatas;
    }
    /**
     * 获得指定的位置上的显示类型
     * */
    @Override
    public int getItemViewType(int position) {
        if (position==getItemCount()-1){
            return  TYPE_FOOTER;
        }
        return  TYPE_COMMON;
    }

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        if (viewType == TYPE_COMMON) {
            View itemView = LayoutInflater.from(context).inflate(R.layout.item_recycler04,parent,false);
            ItemViewHolder itemViewHolder = new ItemViewHolder(itemView);
            return  itemViewHolder;
        }else {
            View footerView = LayoutInflater.from(context).inflate(R.layout.item_footer,parent,false);
            FooterViewHolder holder = new FooterViewHolder(footerView);
            return  holder;
        }
    }

    @Override
    public int getItemCount() {
        return mDatas.size()==0?0:mDatas.size()+1;
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
            if (holder instanceof  ItemViewHolder) {
                ((ItemViewHolder)holder).tv_name.setText(mDatas.get(position).get("title"));
                ((ItemViewHolder)holder).tv_summary.setText(mDatas.get(position).get("summary"));
            }
    }

    class ItemViewHolder extends RecyclerView.ViewHolder{
        TextView tv_name,tv_summary;
        public ItemViewHolder(View itemView) {
            super(itemView);
            tv_name = (TextView)itemView.findViewById(R.id.tv_name);
            tv_summary = (TextView)itemView.findViewById(R.id.tv_summary);
        }
    }

    class FooterViewHolder extends RecyclerView.ViewHolder{

        public FooterViewHolder(View itemView) {
            super(itemView);
        }
    }
}

效果：

实例四;CardView的效果

 <android.support.v7.widget.CardView
        android:id="@+id/id_card"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:cardBackgroundColor="#669900"
        app:cardCornerRadius="10dp"
        app:cardElevation="20dp">

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
            <ImageView
                android:layout_width="80dp"
                android:layout_height="80dp"
                android:layout_centerVertical="true"
                android:src="@mipmap/ic_launcher"/>
            <TextView
                android:layout_width="match_parent"
                android:layout_height="70dp"
                android:layout_margin="10dp"
                android:gravity="center"
                android:padding="10dp"
                android:text="显示效果"
                android:textColor="#000000"
                android:textSize="20sp" />
        </RelativeLayout>
    </android.support.v7.widget.CardView>