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：

<?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="match_parent"
    >

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

• 设置布局管理器和Adapter

public class MainActivity extends AppCompatActivity {

    private RecyclerView mMain_recyclerview;
    private List<String> 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<MainAdapter.ViewHolder> {

    private List<String> mList;

    public MainAdapter(List<String> 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<PortraitAdapter.ViewHolder> {

    private List<Fruit> mFruitList;
    private boolean flag = true;

    public PortraitAdapter(List<Fruit> 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<String> getDatas(final int firstIndex, final int lastIndex) {
        List<String> 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<String> newDatas = getDatas(fromIndex, toIndex);
        if (newDatas.size() > 0) {
            adapter.updateList(newDatas, true);
        } else {
            adapter.updateList(null, false);
        }
    }

Adapter：

public class MyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
    private List<String> 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<String> 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<String> 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<String> 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<String> getDatas(final int firstIndex, final int lastIndex) {
        List<String> 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<String> 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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