实现原理是使用RecyclerView的OnTouchListener方法监听滑动 在adapter里面增加两项footview 其中date.size为显示的加载条，可以自定义，date.size+1为空白的View，我们设置其高度为0 我们通过LinearLayoutManager的 findLastVisibleItemPosition判断显示的最后一条数据，如果是空白view，表示加载条已经完全展示，松开即可刷新。
回弹效果是通过在滑动时动态改变空白view的高度，达到阻尼效果 ，回弹时再动态将其改为0，达到回弹效果，通过loading防止加载过程中滑动导致显示问题 这里的回调采用了Runnable传参
public class RefreshFootAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> { // 上拉加载更多 public static final int SATUS_PULLUP_LOAD_MORE = 0; // 正在加载中 public static final int SATUS_LOADING_MORE = 1; public static final int SATUS_UP_LOADING_MORE = 2; // 上拉加载更多状态-默认为0 private int load_more_status = 0; private LayoutInflater mInflater; private List<String> mTitles = null; private static final int TYPE_ITEM = 0; // 普通Item View private static final int TYPE_FOOTER = 1; // 底部FootView private static final int TYPE_FOOTER_EMPTY = 2; // 底部空白View private static int pagesize; private int eview_height = 1; private long TimeFlag;// 回弹时间 private RecyclerView parent; private boolean loadmare;// 判断当前是可加载更多 private boolean loading;// 判断是否正在加载 private int startY, nowY;// 滑动判断 <span style="white-space:pre"> </span>//构造函数 处理滑动监听 更新等功能 public RefreshFootAdapter(Context context, RecyclerView parent, final LinearLayoutManager linearLayoutManager, int pagesize, final Runnable onloadmore) { this.parent = parent; this.mInflater = LayoutInflater.from(context); this.mTitles = new ArrayList<String>(); for (int i = 0; i < 20; i++) { int index = i + 1; mTitles.add("item" + index); } this.pagesize = pagesize; parent.setOnTouchListener(new OnTouchListener() { @Override public boolean onTouch(View v, MotionEvent ev) { // TODO Auto-generated method stub switch (ev.getAction()) { case MotionEvent.ACTION_MOVE: nowY = (int) ev.getY(); if (RefreshFootAdapter.this.getItemCount() == linearLayoutManager .findLastVisibleItemPosition() + 1) { if (startY == 0) {// 按下 startY = nowY; } int changeY = nowY - startY; RefreshFootAdapter.this .notifyEmptyView((int) (-changeY / 1.3f)); if (loading) { return false; } RefreshFootAdapter.this .changeMoreStatus(RefreshFootAdapter.this.SATUS_UP_LOADING_MORE); loadmare = true; } else { loadmare = false; if (loading) { return false; } RefreshFootAdapter.this .changeMoreStatus(RefreshFootAdapter.this.SATUS_PULLUP_LOAD_MORE); // 普通的滑动 startY = 0; } break; case MotionEvent.ACTION_UP: RefreshFootAdapter.this.resetEmptyView(); if (loadmare) { if (loading) { return false; } else { RefreshFootAdapter.this .changeMoreStatus(RefreshFootAdapter.this.SATUS_LOADING_MORE); if (onloadmore != null && !loading) { loading = true; onloadmore.run(); } } } startY = 0; break; default: break; } return false; } }); } /** * item显示类型 * * @param parent * @param viewType * @return */ public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { // 进行判断显示类型，来创建返回不同的View if (viewType == TYPE_ITEM) { View view = mInflater.inflate(R.layout.item_recycler_layout, parent, false); // 这边可以做一些属性设置，甚至事件监听绑定 // view.setBackgroundColor(Color.RED); ItemViewHolder itemViewHolder = new ItemViewHolder(view); return itemViewHolder; } else if (viewType == TYPE_FOOTER) { View foot_view = mInflater.inflate( R.layout.recycler_load_more_layout, parent, false); // 这边可以做一些属性设置，甚至事件监听绑定 // view.setBackgroundColor(Color.RED); FootViewHolder footViewHolder = new FootViewHolder(foot_view); return footViewHolder; } else if (viewType == TYPE_FOOTER_EMPTY) { View foot_view_empty = mInflater.inflate( R.layout.recycler_load_more_layout_empty, parent, false); // 这边可以做一些属性设置，甚至事件监听绑定 // view.setBackgroundColor(Color.RED); FootEmptyHolder footEmptyViewHolder = new FootEmptyHolder( foot_view_empty); return footEmptyViewHolder; } return null; } /** * 数据的绑定显示 * * @param holder * @param position */ public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) { if (holder instanceof ItemViewHolder) { ((ItemViewHolder) holder).item_tv.setText(mTitles.get(position)); holder.itemView.setTag(position); } else if (holder instanceof FootViewHolder) { FootViewHolder footViewHolder = (FootViewHolder) holder; switch (load_more_status) { case SATUS_PULLUP_LOAD_MORE: footViewHolder.foot_view_item_tv.setText("上拉加载更多..."); break; case SATUS_LOADING_MORE: footViewHolder.foot_view_item_tv.setText("正在加载更多数据..."); break; case SATUS_UP_LOADING_MORE: footViewHolder.foot_view_item_tv.setText("松开加载更多数据..."); break; } } else if (holder instanceof FootEmptyHolder) { FootEmptyHolder footViewHolder = (FootEmptyHolder) holder; footViewHolder.empty.setLayoutParams(new ViewGroup.LayoutParams( 111, eview_height)); } } /** * 进行判断是普通Item视图还是FootView视图 * * @param position * @return */ @Override public int getItemViewType(int position) { // 最后一个item设置为footerView if (position + 1 == getItemCount()) { return TYPE_FOOTER_EMPTY; } else if (position + 2 == getItemCount()) { return TYPE_FOOTER; } else { return TYPE_ITEM; } } <span style="white-space:pre"> </span>//如果是页数的倍数 itemcount+2 @Override public int getItemCount() { if (mTitles.size() % pagesize != 0) { return mTitles.size(); } else { return mTitles.size() + 2; } // return mTitles.size()+1; } // 自定义的ViewHolder，持有每个Item的的所有界面元素 public static class ItemViewHolder extends RecyclerView.ViewHolder { public TextView item_tv; public ItemViewHolder(View view) { super(view); item_tv = (TextView) view.findViewById(R.id.item_tv); } } /** * 底部FootView布局 */ public static class FootViewHolder extends RecyclerView.ViewHolder { private TextView foot_view_item_tv; public FootViewHolder(View view) { super(view); foot_view_item_tv = (TextView) view .findViewById(R.id.foot_view_item_tv); } } <span style="white-space:pre"> </span>//空白项 public static class FootEmptyHolder extends RecyclerView.ViewHolder { private View empty; public FootEmptyHolder(View view) { super(view); empty = view.findViewById(R.id.empty); } } // 添加数据 public void addItem(List<String> newDatas) { // mTitles.add(position, data); // notifyItemInserted(position); newDatas.addAll(mTitles); mTitles.removeAll(mTitles); mTitles.addAll(newDatas); notifyDataSetChanged(); } <span style="white-space:pre"> </span>//更新添加数据 public void addMoreItem(List<String> newDatas) { mTitles.addAll(newDatas); notifyDataSetChanged(); } <span style="white-space:pre"> </span>//更新空白项高度 private void notifyEmptyView(int height) { this.eview_height = height; notifyItemChanged(getItemCount() - 1); } <span style="white-space:pre"> </span>//空白回弹 伪回弹动画 private void resetEmptyView() { final int dx = eview_height; new Thread(new Runnable() { @Override public void run() { // TODO Auto-generated method stub final int time = 500; final long startTime = new Date().getTime(); TimeFlag = startTime; long nowTime = new Date().getTime(); while (startTime + time > nowTime && TimeFlag == startTime) { nowTime = new Date().getTime(); final int dt = (int) (nowTime - startTime); parent.post(new Runnable() { @Override public void run() { // TODO Auto-generated method stub eview_height = eview_height * (time - dt) / time; notifyDataSetChanged(); } }); try { Thread.sleep(10); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } } parent.post(new Runnable() { @Override public void run() { // TODO Auto-generated method stub eview_height = 0; notifyDataSetChanged(); } }); } }).start(); } <span style="white-space:pre"> </span>//停止加载更多 重置loading状态和显示文本 public void stopLoadMore() { notifyDataSetChanged(); loading = false; RefreshFootAdapter.this .changeMoreStatus(RefreshFootAdapter.this.SATUS_PULLUP_LOAD_MORE); } //改变加载条状态 private void changeMoreStatus(int status) { if (loading) { return; } load_more_status = status; notifyDataSetChanged(); } }
图1为滑动过程
图2为松开加载
以上所述是小编给大家介绍的Android RecyclerView上拉加载更多功能回弹实现代码，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对网站的支持！
去追寻那飞翔的翅膀。落叶随风淡定了它漂泊的方向。
