RecyclerView常用功能解析

本篇文章已授权微信公众号 guolin_blog （郭霖）独家发布

1. RecyclerView常用功能

普通的上下滑动和左右滑动
Grid效果上下滑动和左右滑动
瀑布流的上下滑动和左右滑动
添加分割线
添加item之间的空隙
去除最后一个item的分割线
添加点击事件
增加和删除item
添加动画
多布局
下拉刷新和上拉加载
添加头布局和脚布局
拖拽排序和侧滑删除
分页加载、上拉加载、添加脚布局DEMO

2. RecyclerView相关类

RecyclerView.Adapter ：创建子项item布局和绑定数据
RecyclerView.ViewHolder ：生成子项item的布局
RecyclerView.LayoutManager ：设置子项item的排列方式
RecyclerView.ItemDecoration ：设置子项item的分割线
RecyclerView.ItemAnimator ：设置子项item的动画

3. RecyclerView基本实现

依赖：

compile 'com.android.support:recyclerview-v7:26.0.0-alpha1'

布局：

设置布局管理器和Adapter

public class MainActivity extends AppCompatActivity {

    private RecyclerView mMain_recyclerview;
    private List mList;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        initView();
        initData();
        initAdapter();
    }

    //初始化控件
    private void initView() {
        setContentView(R.layout.activity_main);
        mMain_recyclerview = (RecyclerView) findViewById(R.id.main_recyclerview);
    }
    //初始化数据
    private void initData() {
        mList = new ArrayList<>();
        for (int i = 0; i < 10; i++) {
            mList.add("纵向和横向滑动");
            mList.add("纵向和横向瀑布流");
            mList.add("添加头布局和脚布局");
            mList.add("下拉刷新和上拉加载");
            mList.add("多布局页面");
            mList.add("滑动删除");
            mList.add("点击事件");
            mList.add("添加空布局");
            mList.add("添加分割线");
        }
    }
    //初始化Adapter
    private void initAdapter() {
        //设置布局管理器
        mMain_recyclerview.setLayoutManager(new LinearLayoutManager(this));
        //初始化和设置Adapter
        MainAdapter mainAdapter = new MainAdapter(mList);
        mMain_recyclerview.setAdapter(mainAdapter);
    }
}

Adapter：

public class MainAdapter extends RecyclerView.Adapter {

    private List mList;

    public MainAdapter(List list) {
        mList = list;
    }
    
    //创建子项item的布局
    @Override
    public MainAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.main_item, parent, false);
        return new ViewHolder(view);
    }
    
    //给控件设置数据
    @Override
    public void onBindViewHolder(MainAdapter.ViewHolder holder, int position) {
        holder.tv_main.setText(mList.get(position));
    }
    
    //子项item的数量
    @Override
    public int getItemCount() {
        return mList.size();
    }
    
    //初始化子项控件
    static class ViewHolder extends RecyclerView.ViewHolder {

        TextView tv_main;

        public ViewHolder(View itemView) {
            super(itemView);
            this.tv_main = itemView.findViewById(R.id.tv_main);
        }
    }
}

4. RecyclerView左右和上下滑动以及瀑布流：

只需修改布局管理器参数即可：

//ListView形式上下滑动：
mMain_recyclerview.setLayoutManager(new LinearLayoutManager(this));
//左右滑动：
LinearLayoutManager magager = new LinearLayoutManager(this);
magager.setOrientation(LinearLayoutManager.HORIZONTAL);
//Grid形式上下滑动：
GridLayoutManager layoutManager = new GridLayoutManager(this,4);
//Grid形式左右滑动：
GridLayoutManager layoutManager = new GridLayoutManager(this, 4);
layoutManager.setOrientation(GridLayoutManager.HORIZONTAL);
//瀑布流形式上下滑动：
StaggeredGridLayoutManager layoutManager = new
StaggeredGridLayoutManager(4, StaggeredGridLayoutManager.VERTICAL);
//瀑布流形式左右滑动：
StaggeredGridLayoutManager layoutManager = new
StaggeredGridLayoutManager(4, StaggeredGridLayoutManager.HORIZONTAL);

5. ListView形式上下滑动和左右滑动添加分割线：

添加分割线：

mMain_recyclerview.addItemDecoration(new MyDividerItemDecoration(this, MyDividerItemDecoration.VERTICAL_LIST));

MyDividerItemDecoration
ondraw:绘制 getItemOffsets:绘制的区域

public class MyDividerItemDecoration extends RecyclerView.ItemDecoration {

    private static final int[] ATTRS = new int[]{
            android.R.attr.listDivider
    };

    public static final int HORIZONTAL_LIST = LinearLayoutManager.HORIZONTAL;
    public static final int VERTICAL_LIST = LinearLayoutManager.VERTICAL;
    private int mOrientation;
    private Drawable mDivider;
    private int mDividerHeight = 2; //默认是2px
    private Paint mPaint;

    //绘制默认分割线
    public MyDividerItemDecoration(Context context, int orientation) {
        final TypedArray a = context.obtainStyledAttributes(ATTRS);
        mDivider = a.getDrawable(0); //系统属性中获取
        a.recycle();
        setOrientation(orientation);
    }

    /**
     * 自定义分割线
     *
     * @param context
     * @param orientation 列表方向
     * @param drawableId  分割线图片
     */
    public MyDividerItemDecoration(Context context, int orientation, int drawableId) {
        this(context, orientation);
        mDivider = ContextCompat.getDrawable(context, drawableId);
        mDividerHeight = mDivider.getIntrinsicHeight();
    }

    /**
     * 自定义分割线
     *
     * @param context
     * @param orientation   列表方向
     * @param dividerHeight 分割线高度
     * @param dividerColor  分割线颜色
     */
    public MyDividerItemDecoration(Context context, int orientation, int dividerHeight, int dividerColor) {
        this(context, orientation);
        mDividerHeight = dividerHeight;
        mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
        mPaint.setColor(dividerColor);
        mPaint.setStyle(Paint.Style.FILL);
    }

    private void setOrientation(int orientation) {
        if (orientation != HORIZONTAL_LIST && orientation != VERTICAL_LIST) {
            throw new IllegalArgumentException("invalid orientaion");
        }
        mOrientation = orientation;
    }

    @Override //在RecyclerView的onDraw中执行
    public void onDraw(Canvas c, RecyclerView parent) {
        if (mOrientation == VERTICAL_LIST) {
            drawVertical(c, parent);
        } else {
            drawHorizontal(c, parent);
        }
    }

    private void drawHorizontal(Canvas c, RecyclerView parent) {
        final int top = parent.getPaddingTop();
        final int bottom = parent.getHeight() - parent.getPaddingBottom();
        final int childCount = parent.getChildCount();
        for (int i = 0; i < childCount-1; i++) {
            final View child = parent.getChildAt(i);
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
            final int left = child.getRight() + params.rightMargin;
            final int right = left + mDivider.getIntrinsicHeight();
            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }

    private void drawVertical(Canvas c, RecyclerView parent) {
        final int left = parent.getPaddingLeft();
        final int right = parent.getWidth() - parent.getPaddingRight();
        final int childCount = parent.getChildCount();
        for (int i = 0; i < childCount-1; i++) {
            final View child = parent.getChildAt(i);
            RecyclerView v = new RecyclerView(parent.getContext());
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
            final int top = child.getBottom() + params.bottomMargin;
            final int bottom = top + mDivider.getIntrinsicHeight();
            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {

        if (mOrientation == VERTICAL_LIST) {
            outRect.set(0, 0, 0, mDividerHeight);
        } else {
            outRect.set(0, 0, mDividerHeight, 0);
        }
    }
}

6. Grid和瀑布流形式添加分割线

添加分割线：

mRecyclerView.addItemDecoration(new DividerGridItemDecoration(this));

DividerGridItemDecoration（Grid和瀑布流形式都可用）：

public class DividerGridItemDecoration extends RecyclerView.ItemDecoration
{

    private static final int[] ATTRS = new int[] { android.R.attr.listDivider };
    private Drawable mDivider;

    public DividerGridItemDecoration(Context context)
    {
        final TypedArray a = context.obtainStyledAttributes(ATTRS);
        mDivider = a.getDrawable(0);
        a.recycle();
    }

    @Override
    public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state)
    {

        drawHorizontal(c, parent);
        drawVertical(c, parent);

    }

    private int getSpanCount(RecyclerView parent)
    {
        // 列数
        int spanCount = -1;
        RecyclerView.LayoutManager layoutManager = parent.getLayoutManager();
        if (layoutManager instanceof GridLayoutManager)
        {

            spanCount = ((GridLayoutManager) layoutManager).getSpanCount();
        } else if (layoutManager instanceof StaggeredGridLayoutManager)
        {
            spanCount = ((StaggeredGridLayoutManager) layoutManager)
                    .getSpanCount();
        }
        return spanCount;
    }

    public void drawHorizontal(Canvas c, RecyclerView parent)
    {
        int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++)
        {
            final View child = parent.getChildAt(i);
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child
                    .getLayoutParams();
            final int left = child.getLeft() - params.leftMargin;
            final int right = child.getRight() + params.rightMargin
                    + mDivider.getIntrinsicWidth();
            final int top = child.getBottom() + params.bottomMargin;
            final int bottom = top + mDivider.getIntrinsicHeight();
            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }

    public void drawVertical(Canvas c, RecyclerView parent)
    {
        final int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++)
        {
            final View child = parent.getChildAt(i);

            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child
                    .getLayoutParams();
            final int top = child.getTop() - params.topMargin;
            final int bottom = child.getBottom() + params.bottomMargin;
            final int left = child.getRight() + params.rightMargin;
            final int right = left + mDivider.getIntrinsicWidth();

            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }

    private boolean isLastColum(RecyclerView parent, int pos, int spanCount,
                                int childCount)
    {
        RecyclerView.LayoutManager layoutManager = parent.getLayoutManager();
        if (layoutManager instanceof GridLayoutManager)
        {
            if ((pos + 1) % spanCount == 0)// 如果是最后一列，则不需要绘制右边
            {
                return true;
            }
        } else if (layoutManager instanceof StaggeredGridLayoutManager)
        {
            int orientation = ((StaggeredGridLayoutManager) layoutManager)
                    .getOrientation();
            if (orientation == StaggeredGridLayoutManager.VERTICAL)
            {
                if ((pos + 1) % spanCount == 0)// 如果是最后一列，则不需要绘制右边
                {
                    return true;
                }
            } else
            {
                childCount = childCount - childCount % spanCount;
                if (pos >= childCount)// 如果是最后一列，则不需要绘制右边
                    return true;
            }
        }
        return false;
    }

    private boolean isLastRaw(RecyclerView parent, int pos, int spanCount,
                              int childCount)
    {
        RecyclerView.LayoutManager layoutManager = parent.getLayoutManager();
        if (layoutManager instanceof GridLayoutManager)
        {
            childCount = childCount - childCount % spanCount;
            if (pos >= childCount)// 如果是最后一行，则不需要绘制底部
                return true;
        } else if (layoutManager instanceof StaggeredGridLayoutManager)
        {
            int orientation = ((StaggeredGridLayoutManager) layoutManager)
                    .getOrientation();
            // StaggeredGridLayoutManager 且纵向滚动
            if (orientation == StaggeredGridLayoutManager.VERTICAL)
            {
                childCount = childCount - childCount % spanCount;
                // 如果是最后一行，则不需要绘制底部
                if (pos >= childCount)
                    return true;
            } else
            // StaggeredGridLayoutManager 且横向滚动
            {
                // 如果是最后一行，则不需要绘制底部
                if ((pos + 1) % spanCount == 0)
                {
                    return true;
                }
            }
        }
        return false;
    }

    @Override
    public void getItemOffsets(Rect outRect, int itemPosition,
                               RecyclerView parent)
    {
        int spanCount = getSpanCount(parent);
        int childCount = parent.getAdapter().getItemCount();
        if (isLastRaw(parent, itemPosition, spanCount, childCount))// 如果是最后一行，则不需要绘制底部
        {
            outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0);
        } else if (isLastColum(parent, itemPosition, spanCount, childCount))// 如果是最后一列，则不需要绘制右边
        {
            outRect.set(0, 0, 0, mDivider.getIntrinsicHeight());
        } else
        {
            outRect.set(0, 0, mDivider.getIntrinsicWidth(),
                    mDivider.getIntrinsicHeight());
        }
    }
}

7. 添加item之间的空隙

public class SpacesItemDecoration extends RecyclerView.ItemDecoration {

    private int leftRight;
    private int topBottom;

    public SpacesItemDecoration(int leftRight, int topBottom) {
        this.leftRight = leftRight;
        this.topBottom = topBottom;
    }

    @Override
    public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
      super.onDraw(c, parent, state);
    }

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
        LinearLayoutManager layoutManager = (LinearLayoutManager) parent.getLayoutManager();
        //竖直方向的
        if (layoutManager.getOrientation() == LinearLayoutManager.VERTICAL) {
            //最后一项需要 bottom
            if (parent.getChildAdapterPosition(view) == layoutManager.getItemCount() - 1) {
                outRect.bottom = topBottom;
            }
            outRect.top = topBottom;
            outRect.left = leftRight;
            outRect.right = leftRight;
        } else {
            //最后一项需要right
            if (parent.getChildAdapterPosition(view) == layoutManager.getItemCount() - 1) {
                outRect.right = leftRight;
            }
            outRect.top = topBottom;
            outRect.left = leftRight;
            outRect.bottom = topBottom;
        }
    }
}

int leftRight = DisplayUtil.dp2px(8);
int topBottom = DisplayUtil.dp2px(8);
mRecyclerView.addItemDecoration(new SpacesItemDecoration(leftRight, topBottom));

8. RecyclerView去除最后一个item的分割线

ListView形式：在上面的分割线绘制部分，我们只绘制了childCount-1个，所以上面的分割线，已经不会绘制最后一条item的分割线了。
Grid和瀑布流形式：首先去判断是不是最后一行或者一列，然后在getItemOffsets方法中不绘制底部或者右边，上面的部分已经实现。

9. RecyclerView添加点击事件

处理点击事件，只需要在Adapter中处理即可（不推荐）

public class PortraitAdapter extends RecyclerView.Adapter {

    private List mFruitList;
    private boolean flag = true;

    public PortraitAdapter(List fruitList) {
        mFruitList = fruitList;
    }

    static class ViewHolder extends RecyclerView.ViewHolder {
        
        ImageView fruitImage;
        TextView fruitName;
        LinearLayout ll_portraitscape;

        public ViewHolder(View view) {
            super(view);
            fruitImage = (ImageView) view.findViewById(R.id.fruit_image);
            fruitName = (TextView) view.findViewById(R.id.fruit_name);
            ll_portraitscape = (LinearLayout) view.findViewById(R.id.ll_portraitscape);
        }
    }

    @Override
    public ViewHolder onCreateViewHolder(final ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_portrait, parent, false);
        final ViewHolder holder = new ViewHolder(view);
        holder.ll_portraitscape.setOnLongClickListener(new View.OnLongClickListener() {
            @Override
            public boolean onLongClick(View v) {
                new AlertDialog.Builder(v.getContext())
                        .setTitle("确认删除吗")
                        .setNegativeButton("取消",null)
                        .setPositiveButton("确定", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                if (flag == true){
                                    removeData(holder.getAdapterPosition());
                                    flag=false;
                                }else{
                                    addData(holder.getAdapterPosition());
                                    flag=true;
                                }

                            }
                        })
                        .show();
                return false;
            }
        });
        holder.fruitImage.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Toast.makeText(parent.getContext(),"我是图片短点击",Toast.LENGTH_SHORT).show();
            }
        });
        return holder;
    }

    @Override
    public void onBindViewHolder(final ViewHolder holder, int position) {
        Fruit fruit = mFruitList.get(position);
        holder.fruitImage.setImageResource(fruit.getImageId());
        holder.fruitName.setText(fruit.getName());
    }

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

    public void addData(int position) {
        mFruitList.add(position, new Fruit("Apple", R.drawable.apple_pic));
        notifyItemInserted(position);
    }

    public void removeData(int position) {
        mFruitList.remove(position);
        notifyItemRemoved(position);
    }

}

只需要在onCreateViewHolder中处理即可，可以很轻松实现子项中任意控件或布局的点击事件。

在Adapter中定义接口并提供回调（推荐）

Adapter：
public interface OnItemClickListener{
    void onItemClick(View view,int position);
    void onItemLongClick(View view,int position);
}
public void setOnItemClickListener(OnItemClickListener mOnItemClickListener){
    this.mOnItemClickListener = mOnItemClickListener;
}

onBindViewHolder：
if (mOnItemClickListener!=null){
    holder.tv.setOnClickListener(new View.OnClickListener(){
        @Override
        public void onClick(View v){
            int pos = holder.getLayoutPosition();
            mOnItemClickListener.onItemClick(holder.tv,pos);
        }
    });
    holder.tv.setOnLongClickListener(new View.OnLongClickListener(){
        @Override
        public boolean onLongClick(View view){
            int pos = holder.getLayoutPosition();
            mOnItemClickListener.onItemLongClick(holder.tv,pos);
            return false;
        }
    }
}

Activity:
mHomeAdapter.setOnItemClickListener(new HomeAdapter.OnItemClickListener(){
    @Override
    public void onItemClick(View view,int position){
        ...
    }
    @Override
    public void onItemLongClick(View view,final int position){
        ...
    }
}

10. RecyclerView增加和删除item

在Adapter添加两种方法

public void addData(int position) {
        mFruitList.add(position, new Fruit("Apple", R.drawable.apple_pic));
        notifyItemInserted(position);
    }

    public void removeData(int position) {
        mFruitList.remove(position);
        notifyItemRemoved(position);
    }

在Adapter中的onCreateViewHolder中的点击事件里面添加动作

holder.ll_portraitscape.setOnLongClickListener(new View.OnLongClickListener() {
            @Override
            public boolean onLongClick(View v) {
                new AlertDialog.Builder(v.getContext())
                        .setTitle("确认删除吗")
                        .setNegativeButton("取消",null)
                        .setPositiveButton("确定", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                if (flag == true){
                                    removeData(holder.getAdapterPosition());
                                    flag=false;
                                }else{
                                    addData(holder.getAdapterPosition());
                                    flag=true;
                                }

                            }
                        })
                        .show();
                return false;
            }
        });

11. RecyclerView添加动画效果

默认的动画：

mRecyclerView.setItemAnimator(new DefaultItemAnimator());

自定义的动画：

private int mLastPosition;//放在成员变量的位置上

if (viewHolder.getAdapterPosition() > mLastPosition) {
    ObjectAnimator scaleX = ObjectAnimator.ofFloat(viewHolder.itemView, "scaleX", 0.5f, 1f);
    scaleX.start();
    mLastPosition = viewHolder.getLayoutPosition();
}

说明:实现的方式有很多种，这里介绍一种，就是在RecyclerView的onBindViewHolder中利用属性动画就可以实现非常华丽的效果。

12. RecyclerView多布局

实现多布局最核心的方法就是在Adapter中重写getItemViewType方法：

@Override
public int getItemViewType(int position) {
    if (mNewsBeanList.get(position).getThumbnail_pic_s03() == null) {
        return IMAGE_ONLY_ONE;
    } else {
        return IMAGE_TWOORTHREE;
    }
}

说明：判断下布局的不同，返回不同的值，不同的值就代表了不多的布局。

在onCreateViewHolder方法中第二个参数对应的就是上面方法返回的值，我们根据值的不同，填充不同的布局。

@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType) {
    if (viewType == IMAGE_TWOORTHREE) {
        View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.news_imagethree_item, viewGroup, false);
         ImageThreeViewHolder viewHolder = new ImageThreeViewHolder(view);
        return viewHolder;
    } else {
        View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.news_imageonly_item, viewGroup, false);
        ImageOnlyOneViewHolder viewHolder = new ImageOnlyOneViewHolder(view);
        return viewHolder;
    }
}

不同的布局需要不同的ViewHolder

    static class ImageThreeViewHolder extends RecyclerView.ViewHolder {

        private TextView mTv_title;
        private ImageView mIv_image01;
        private ImageView mIv_image02;
        private ImageView mIv_image03;
        private TextView mTv_company;
        private TextView mTv_time;
        private View mItemView;

        public ImageThreeViewHolder(View itemView) {
            super(itemView);
            mItemView = itemView;
            mTv_title = itemView.findViewById(R.id.tv_title);
            mIv_image01 = itemView.findViewById(R.id.iv_image01);
            mIv_image02 = itemView.findViewById(R.id.iv_image02);
            mIv_image03 = itemView.findViewById(R.id.iv_image03);
            mTv_company = itemView.findViewById(R.id.tv_company);
            mTv_time = itemView.findViewById(R.id.tv_time);
        }
    }

    static class ImageOnlyOneViewHolder extends RecyclerView.ViewHolder {

        private View mItemView;
        private TextView mTv_title;
        private TextView mTv_company;
        private TextView mTv_time;
        private ImageView mIv_image01;

        public ImageOnlyOneViewHolder(View itemView) {
            super(itemView);
            mItemView = itemView;
            mTv_title = itemView.findViewById(R.id.tv_title);
            mTv_company = itemView.findViewById(R.id.tv_company);
            mTv_time = itemView.findViewById(R.id.tv_time);
            mIv_image01 = itemView.findViewById(R.id.iv_image01);
        }
    }

onBindViewHolder方法中的第一个参数对应不同的viewholder，我们通过判断，来进行每个元素的写入

@Override
    public void onBindViewHolder(RecyclerView.ViewHolder viewHolder, int position) {
        if (viewHolder instanceof ImageThreeViewHolder) {
            ((ImageThreeViewHolder) viewHolder).mTv_title.setText(mNewsBeanList.get(position).getTitle());
            ((ImageThreeViewHolder) viewHolder).mTv_company.setText(mNewsBeanList.get(position).getAuthor_name());
            ((ImageThreeViewHolder) viewHolder).mTv_time.setText(mNewsBeanList.get(position).getDate());

            Glide.with(mContext).load(mNewsBeanList.get(position).getThumbnail_pic_s()).into(((ImageThreeViewHolder) viewHolder).mIv_image01);
            Glide.with(mContext).load(mNewsBeanList.get(position).getThumbnail_pic_s02()).into(((ImageThreeViewHolder) viewHolder).mIv_image02);
            Glide.with(mContext).load(mNewsBeanList.get(position).getThumbnail_pic_s03()).into(((ImageThreeViewHolder) viewHolder).mIv_image03);
        } else if (viewHolder instanceof ImageOnlyOneViewHolder) {
            ((ImageOnlyOneViewHolder) viewHolder).mTv_title.setText(mNewsBeanList.get(position).getTitle());
            ((ImageOnlyOneViewHolder) viewHolder).mTv_company.setText(mNewsBeanList.get(position).getAuthor_name());
            ((ImageOnlyOneViewHolder) viewHolder).mTv_time.setText(mNewsBeanList.get(position).getDate());

            Glide.with(mContext).load(mNewsBeanList.get(position).getThumbnail_pic_s()).into(((ImageOnlyOneViewHolder) viewHolder).mIv_image01);

        }
      
    }

13. RecyclerView 上拉刷新和下拉加载

下拉刷新（借助SwipeRefreshLayout）


    private void initRefresh() {
        srRefresh.setColorSchemeResources(R.color.colorPrimary);
        srRefresh.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
            @Override
            public void onRefresh() {
                refreshFruits();
            }
        });
    }

    private void refreshFruits() {
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    Thread.sleep(2000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        initFruits();
                        adapter.notifyDataSetChanged();
                        srRefresh.setRefreshing(false);
                    }
                });
            }
        }).start();
    }

    private void initFruits() {
        fruitList.clear();
        for (int i = 0; i < 50; i++) {
            Random random = new Random();
            int index = random.nextInt(fruits.length);
            fruitList.add(fruits[index]);
        }
    }

说明：SwipeRefreshLayout设置一个监听器：setOnRefreshListener，onRefresh方法中进行数据更新的操作。

上拉加载

recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
            @Override
            public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
                super.onScrollStateChanged(recyclerView, newState);
                if (newState == RecyclerView.SCROLL_STATE_IDLE) {

                    if (adapter.isFadeTips() == false && lastVisibleItem + 1 == adapter.getItemCount()) {
                        mHandler.postDelayed(new Runnable() {
                            @Override
                            public void run() {
                                updateRecyclerView(adapter.getRealLastPosition(), adapter.getRealLastPosition() + PAGE_COUNT);
                            }
                        }, 500);
                    }

                    if (adapter.isFadeTips() == true && lastVisibleItem + 2 == adapter.getItemCount()) {
                        mHandler.postDelayed(new Runnable() {
                            @Override
                            public void run() {
                                updateRecyclerView(adapter.getRealLastPosition(), adapter.getRealLastPosition() + PAGE_COUNT);
                            }
                        }, 500);
                    }
                }
            }

            @Override
            public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
                super.onScrolled(recyclerView, dx, dy);
                lastVisibleItem = mLayoutManager.findLastVisibleItemPosition();
              
            }
        });

说明：recyclerView添加滑动监听器addOnScrollListener，在onScrollStateChanged方法中处理加载的动作。

14. RecyclerView添加头布局和脚布局

添加头布局和脚布局，其实和实现多布局一模一样，不再赘述。

15. RecyclerView拖曳排序和侧滑删除

private void initBind() {
        //为RecycleView绑定触摸事件
        ItemTouchHelper helper = new ItemTouchHelper(new ItemTouchHelper.Callback() {
            @Override
            public int getMovementFlags(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder) {
                //侧滑删除
                int swipeFlags = ItemTouchHelper.LEFT | ItemTouchHelper.RIGHT;
                //首先回调的方法 返回int表示是否监听该方向
                int dragFlags = ItemTouchHelper.UP | ItemTouchHelper.DOWN | ItemTouchHelper.LEFT | ItemTouchHelper.RIGHT;//拖拽
                return makeMovementFlags(dragFlags, swipeFlags);
            }

            @Override
            public boolean onMove(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, RecyclerView.ViewHolder target) {
                //滑动事件
                Collections.swap(list, viewHolder.getAdapterPosition(), target.getAdapterPosition());
                adapter.notifyItemMoved(viewHolder.getAdapterPosition(), target.getAdapterPosition());
                return false;
            }

            @Override
            public void onSwiped(RecyclerView.ViewHolder viewHolder, int direction) {
                //侧滑事件
                list.remove(viewHolder.getAdapterPosition());
                adapter.notifyItemRemoved(viewHolder.getAdapterPosition());
            }

            @Override
            public boolean isLongPressDragEnabled() {
                //是否可拖拽
                return true;
            }
        });
        helper.attachToRecyclerView(recyclerView);
    }

16. 分页加载、上拉加载、添加脚布局DEMO

分页加载的核心代码：

private final int PAGE_COUNT = 10;

adapter = new MyAdapter(getDatas(0, PAGE_COUNT), this, getDatas(0, PAGE_COUNT).size() > 0 ? true : false);

private List getDatas(final int firstIndex, final int lastIndex) {
        List resList = new ArrayList<>();
        for (int i = firstIndex; i < lastIndex; i++) {
            if (i < list.size()) {
                resList.add(list.get(i));
            }
        }
        return resList;
    }

    private void updateRecyclerView(int fromIndex, int toIndex) {
        List newDatas = getDatas(fromIndex, toIndex);
        if (newDatas.size() > 0) {
            adapter.updateList(newDatas, true);
        } else {
            adapter.updateList(null, false);
        }
    }

Adapter：

public class MyAdapter extends RecyclerView.Adapter {
    private List datas;
    private Context context;
    private int normalType = 0;
    private int footType = 1;
    private boolean hasMore = true;
    private boolean fadeTips = false;
    private Handler mHandler = new Handler(Looper.getMainLooper());
    private static final String TAG = "MyAdapter";

    public MyAdapter(List datas, Context context, boolean hasMore) {
        this.datas = datas;
        this.context = context;
        this.hasMore = hasMore;
    }

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        if (viewType == normalType) {
            return new NormalHolder(LayoutInflater.from(context).inflate(R.layout.item, null));
        } else {
            return new FootHolder(LayoutInflater.from(context).inflate(R.layout.footview, null));
        }
    }

    @Override
    public void onBindViewHolder(final RecyclerView.ViewHolder holder, int position) {
        if (holder instanceof NormalHolder) {
            ((NormalHolder) holder).textView.setText(datas.get(position));
        } else {
            ((FootHolder) holder).tips.setVisibility(View.VISIBLE);
            if (hasMore == true) {
                fadeTips = false;
                if (datas.size() > 0) {
                    ((FootHolder) holder).tips.setText("正在加载更多...");
                }
            } else {
                if (datas.size() > 0) {
                    ((FootHolder) holder).tips.setText("没有更多数据了");
                    mHandler.postDelayed(new Runnable() {
                        @Override
                        public void run() {
                            ((FootHolder) holder).tips.setVisibility(View.GONE);
                            fadeTips = true;
                            hasMore = true;
                        }
                    }, 500);
                }
            }
        }
    }

    @Override
    public int getItemCount() {
        return datas.size() + 1;
    }

    public int getRealLastPosition() {
        return datas.size();
    }

    public void updateList(List newDatas, boolean hasMore) {
        if (newDatas != null) {
            datas.addAll(newDatas);
        }
        this.hasMore = hasMore;
        notifyDataSetChanged();
    }

    class NormalHolder extends RecyclerView.ViewHolder {
        private TextView textView;

        public NormalHolder(View itemView) {
            super(itemView);
            textView = (TextView) itemView.findViewById(R.id.tv);
        }
    }

    class FootHolder extends RecyclerView.ViewHolder {
        private TextView tips;

        public FootHolder(View itemView) {
            super(itemView);
            tips = (TextView) itemView.findViewById(R.id.tips);
        }
    }

    public boolean isFadeTips() {
        return fadeTips;
    }

    public void resetDatas() {
        datas = new ArrayList<>();
    }

    @Override
    public int getItemViewType(int position) {
        Log.e(TAG,"getItemCount()::"+getItemCount());
        Log.e(TAG,"position::"+position);

        if (position == getItemCount() - 1) {
            return footType;
        } else {
            return normalType;
        }
    }
}

Activity:

public class MainActivity extends AppCompatActivity implements SwipeRefreshLayout.OnRefreshListener {
    private SwipeRefreshLayout refreshLayout;
    private RecyclerView recyclerView;
    private List list;

    private int lastVisibleItem = 0;
    private final int PAGE_COUNT = 10;
    private LinearLayoutManager mLayoutManager;
    private MyAdapter adapter;
    private Handler mHandler = new Handler(Looper.getMainLooper());
    private static final String TAG = "MainActivity";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initData();
        findView();
        initRefreshLayout();
        initRecyclerView();
    }

    private void initData() {
        list = new ArrayList<>();
        for (int i = 1; i <= 40; i++) {
            list.add("条目" + i);
        }
    }


    private void findView() {
        refreshLayout = (SwipeRefreshLayout) findViewById(R.id.refreshLayout);
        recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
    }

    private void initRefreshLayout() {
        refreshLayout.setColorSchemeResources(android.R.color.holo_blue_light, android.R.color.holo_red_light,
                android.R.color.holo_orange_light, android.R.color.holo_green_light);
        refreshLayout.setOnRefreshListener(this);
    }

    private void initRecyclerView() {
        adapter = new MyAdapter(getDatas(0, PAGE_COUNT), this, getDatas(0, PAGE_COUNT).size() > 0 ? true : false);
        mLayoutManager = new LinearLayoutManager(this);
        recyclerView.setLayoutManager(mLayoutManager);
        recyclerView.setAdapter(adapter);
        recyclerView.setItemAnimator(new DefaultItemAnimator());

        recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
            @Override
            public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
                super.onScrollStateChanged(recyclerView, newState);
                if (newState == RecyclerView.SCROLL_STATE_IDLE) {

                    if (adapter.isFadeTips() == false && lastVisibleItem + 1 == adapter.getItemCount()) {
                        mHandler.postDelayed(new Runnable() {
                            @Override
                            public void run() {
                                updateRecyclerView(adapter.getRealLastPosition(), adapter.getRealLastPosition() + PAGE_COUNT);
                            }
                        }, 500);
                    }

                    if (adapter.isFadeTips() == true && lastVisibleItem + 2 == adapter.getItemCount()) {
                        mHandler.postDelayed(new Runnable() {
                            @Override
                            public void run() {
                                Log.e(TAG, "lastVisibleItem::" + lastVisibleItem);
                                Log.e(TAG, "adapter.getItemCount()::" + adapter.getItemCount());
                                updateRecyclerView(adapter.getRealLastPosition(), adapter.getRealLastPosition() + PAGE_COUNT);
                            }
                        }, 500);
                    }
                }
            }

            @Override
            public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
                super.onScrolled(recyclerView, dx, dy);
                lastVisibleItem = mLayoutManager.findLastVisibleItemPosition();
                Log.e(TAG, "lastVisibleItem::" + lastVisibleItem);
                Log.e(TAG, "adapter.getItemCount()::" + adapter.getItemCount());
            }
        });
    }

    private List getDatas(final int firstIndex, final int lastIndex) {
        List resList = new ArrayList<>();
        for (int i = firstIndex; i < lastIndex; i++) {
            if (i < list.size()) {
                resList.add(list.get(i));
            }
        }
        return resList;
    }

    private void updateRecyclerView(int fromIndex, int toIndex) {
        List newDatas = getDatas(fromIndex, toIndex);
        if (newDatas.size() > 0) {
            adapter.updateList(newDatas, true);
        } else {
            adapter.updateList(null, false);
        }
    }

    @Override
    public void onRefresh() {
        refreshLayout.setRefreshing(true);
        adapter.resetDatas();
        updateRecyclerView(0, PAGE_COUNT);
        mHandler.postDelayed(new Runnable() {
            @Override
            public void run() {
                refreshLayout.setRefreshing(false);
            }
        }, 1000);
    }
}

详细说明：http://blog.csdn.net/ljcITworld/article/details/70160820

下载地址：https://github.com/OnlyYouMyLove/PullToLoadData-RecyclerView

17. 后续

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