Android RecyclerView 上拉加载更多及下拉刷新功能的实现方法

package com.krain.srecyclerview.fruitview;import android.content.Context;import android.graphics.drawable.AnimationDrawable;import android.util.AttributeSet;import android.view.LayoutInflater;import android.view.View;import android.widget.FrameLayout;import android.widget.ImageView;import com.krain.srecyclerview.R;/*** Created by dafuShao on 2016/9/9 0009.**/public class ElizabethView extends FrameLayout {private ImageView imageView;private AnimationDrawable animationDrawable;public ElizabethView(Context context) {super(context);initview(context);}public ElizabethView(Context context, AttributeSet attrs) {super(context, attrs);initview(context);}public ElizabethView(Context context, AttributeSet attrs, int defStyleAttr) {super(context, attrs, defStyleAttr);initview(context);}private void initview(Context context){View view= LayoutInflater.from(context).inflate(R.layout.elizabeth_item,null);imageView=(ImageView) view.findViewById(R.id.elizabeth_im);animationDrawable= (AnimationDrawable) imageView.getBackground();addView(view);}@Overrideprotected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {super.onMeasure(widthMeasureSpec, heightMeasureSpec);}//开始动画public void startAnim(){animationDrawable.start();}//停止动画public void stopAnim(){animationDrawable.stop();}}

package com.krain.srecyclerview.srecyclerview;import android.content.Context;import android.os.Handler;import android.os.Message;import android.support.v4.view.MotionEventCompat;import android.support.v7.widget.DefaultItemAnimator;import android.support.v7.widget.GridLayoutManager;import android.support.v7.widget.LinearLayoutManager;import android.support.v7.widget.RecyclerView;import android.support.v7.widget.StaggeredGridLayoutManager;import android.util.AttributeSet;import android.view.LayoutInflater;import android.view.MotionEvent;import android.view.View;import android.view.ViewGroup;import android.widget.LinearLayout;import android.widget.ProgressBar;import android.widget.Scroller;import android.widget.TextView;import com.krain.srecyclerview.R;import com.krain.srecyclerview.fruitview.ElizabethView;public class SRecyclerView extends ViewGroup {Context context;RecyclerView mRecyclerView;ElizabethView mHeaderView;TextView mFootViewTips;//footview的文字显示AdapterWrapper mAdapter;boolean mIsTop = true;//是否滑动到了最顶部RecyclerView.LayoutManager mLayoutManager;int mLastVisibleItem;int mFirstVisibleItem;OnRecyclerStatusChangeListener mRecyclerChangeListener;int mStatus;//当前状态int mHeadviewHeight;//headview的高度Scroller mScroller;int mFristScollerY;//最开始的getscrollyboolean mHasFooter;//是否有上拉加载的功能boolean mShowFootVisible;//是否显示FOOTERview在mHasFooter为true的时候生效boolean mHasRefresh = true;//是否支持下拉刷新private final int DEFAULT_MIN_PAGEINDEX = 1;//默认最小的页数int mMaxPage = DEFAULT_MIN_PAGEINDEX;//分页的总页数int mCurrentPage = DEFAULT_MIN_PAGEINDEX;//当前的页数，从1开始private final int STATUS_NORMAL = 0, STATUS_REFRESH = 1, STATUS_LOAD = 2;private final int MSG_LOAD_COMPLETE = 1, MSG_REFRESH_COMPLETE = 0;//handle的常量private final int DELAY_LOAD_COMPLETE = 1000, DELAY_REFRESH_COMPLETE = 1000;//加载完成延时回收的时间public SRecyclerView(Context context) {super(context);init(context);}public SRecyclerView(Context context, AttributeSet attrs) {super(context, attrs);init(context);}public SRecyclerView(Context context, AttributeSet attrs, int defStyleAttr) {super(context, attrs, defStyleAttr);init(context);}/*** 设置最大页数** @param maxPage*/public void setMaxPage(int maxPage) {this.mMaxPage = maxPage;}/*** 是否支持上拉加载** @param hasLoadmore*/public void setLoadmore(boolean hasLoadmore) {mHasFooter = hasLoadmore;}public void setRecyclerViewLayoutManage(RecyclerView.LayoutManager mLayoutManage){this.mLayoutManager=mLayoutManage;}/*** 关闭下拉刷新功能*/public void disableRefresh() {mHasRefresh = false;}public void setAdapter(BaseRecyclerViewAdapter adapter) {int height = 0;if (mMaxPage == DEFAULT_MIN_PAGEINDEX) {mHasFooter = false;}mAdapter = new AdapterWrapper(context, adapter);mRecyclerView.setAdapter(mAdapter);}private int getViewHeight(View view) {int measure = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);view.measure(measure, measure);return view.getMeasuredHeight();}/*** 获取viewgroup里面的recyclerview** @return*/public RecyclerView getRecyclerView() {return mRecyclerView;}public void setOnRecyclerChangeListener(OnRecyclerStatusChangeListener listener) {mRecyclerChangeListener = listener;}/*** 设置RecyclerView添加、删除Item的动画** @param animator*/public void setItemAnimator(RecyclerView.ItemAnimator animator) {mRecyclerView.setItemAnimator(animator);}public void notifyDataSetChanged() {mStatus = STATUS_NORMAL;//重新set数据代表loadmore结束了，此时恢复成普通状态mAdapter.notifyDataSetChanged();}public void notifyDataInsert(int positionStart, int itemCount) {mStatus = STATUS_NORMAL;//重新set数据代表loadmore结束了，此时恢复成普通状态mAdapter.notifyItemRangeInserted(positionStart, itemCount);}public void notifyDataRemove(int position) {mStatus = STATUS_NORMAL;//重新set数据代表loadmore结束了，此时恢复成普通状态mAdapter.notifyItemRemoved(position);}/*** 初始化操作** @param context*/void init(Context context) {this.context = context;mScroller = new Scroller(context);// if (mLayoutManager!=null){// addChildView(context,mLayoutManager);// }else{// addChildView(context, new LinearLayoutManager(context));// }addChildView(context);}@Overridepublic void computeScroll() {if (mScroller.computeScrollOffset()) {scrollTo(mScroller.getCurrX(), mScroller.getCurrY());postInvalidate();}}/*** 增加子View** @param context*/void addChildView(Context context, RecyclerView.LayoutManager mLayoutManager) {ViewGroup.LayoutParams params = new ViewGroup.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);mHeaderView = new ElizabethView(context);mRecyclerView = new RecyclerView(context);addView(mHeaderView);addView(mRecyclerView);//mLayoutManager = new LinearLayoutManager(context);// mLayoutManager = new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.VERTICAL);mRecyclerView.setLayoutManager(mLayoutManager);// 设置Item增加、移除默认动画mRecyclerView.setItemAnimator(new DefaultItemAnimator());mRecyclerView.addOnScrollListener(onScrollListener);mRecyclerView.setHasFixedSize(true);mRecyclerView.setLayoutParams(params);}void addChildView(Context contex) {ViewGroup.LayoutParams params = new ViewGroup.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);mHeaderView = new ElizabethView(context);mRecyclerView = new RecyclerView(context);addView(mHeaderView);addView(mRecyclerView);//mLayoutManager = new LinearLayoutManager(context);mLayoutManager = new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.VERTICAL);mRecyclerView.setLayoutManager(mLayoutManager);// 设置Item增加、移除默认动画mRecyclerView.setItemAnimator(new DefaultItemAnimator());mRecyclerView.addOnScrollListener(onScrollListener);mRecyclerView.setHasFixedSize(true);mRecyclerView.setLayoutParams(params);}/*** 屏蔽Recyclerview的触摸事件（下拉刷新的时候）*/float lastY;@Overridepublic boolean onInterceptTouchEvent(MotionEvent ev) {final int action = MotionEventCompat.getActionMasked(ev);switch (action) {case MotionEvent.ACTION_DOWN:lastY = ev.getRawY();break;case MotionEvent.ACTION_UP:case MotionEvent.ACTION_CANCEL:return false;case MotionEvent.ACTION_MOVE:if (mHasRefresh && mIsTop && ev.getRawY() > lastY)return true;break;}return false;}float offsetY = 0;@Overridepublic boolean onTouchEvent(MotionEvent event) {switch (event.getAction()) {case MotionEvent.ACTION_MOVE:offsetY = Math.abs(event.getRawY() - lastY); //Y差值绝对值if (offsetY > 0)scrollToOffset(offsetY);else {mIsTop = false;}break;case MotionEvent.ACTION_UP:if (getScrollY() <= 0) {doRefresh();mHeaderView.stopAnim();mHeaderView.startAnim();} else complete();break;}return super.onTouchEvent(event);}/*** 滚动这个view到手滑动的位置** @param offsetY Y轴偏移量*/void scrollToOffset(float offsetY) {//假如正在刷新并且现在的scrolly和初始值一样的时候，代表准备下拉开始刷新，并执行一次onlyif (getScrollY() == mFristScollerY && mRecyclerChangeListener != null)mRecyclerChangeListener.startRefresh();int value = Math.round(offsetY / 2.0F);value = mFristScollerY - value;scrollTo(0, value);}/*** 执行刷新操作,移动到header刚出来的位置*/void doRefresh() {mStatus = STATUS_REFRESH;int currentY = getScrollY();mScroller.startScroll(0, currentY, 0, (mFristScollerY - mHeadviewHeight) - currentY);invalidate();if (mRecyclerChangeListener != null) mRecyclerChangeListener.onRefresh();handler.sendEmptyMessageDelayed(MSG_REFRESH_COMPLETE, DELAY_REFRESH_COMPLETE);}Handler handler = new Handler() {@Overridepublic void handleMessage(Message msg) {super.handleMessage(msg);if (msg.what == MSG_LOAD_COMPLETE) {View footview = mAdapter.getFootView();if (footview != null)mRecyclerView.smoothScrollBy(0, -footview.getMeasuredHeight());} else if (msg.what == MSG_REFRESH_COMPLETE)complete();}};/*** header返回原处完全隐藏*/public void complete() {mCurrentPage = DEFAULT_MIN_PAGEINDEX;//完成之后当前的page恢复默认值if (mFootViewTips != null)mFootViewTips.setText(context.getString(R.string.loading));//更改foot提示为正在加载中if (mRecyclerChangeListener != null) mRecyclerChangeListener.refreshComplete();mStatus = STATUS_NORMAL;int currentY = getScrollY();mScroller.startScroll(0, currentY, 0, mFristScollerY - currentY);mHeaderView.stopAnim();invalidate();}@Overrideprotected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {int width = MeasureSpec.getSize(widthMeasureSpec);int height = 0;for (int i = 0; i < getChildCount(); i++) {View child = getChildAt(i);measureChild(child, widthMeasureSpec, heightMeasureSpec);height += child.getMeasuredHeight();}setMeasuredDimension(width, height);}@Overrideprotected void onLayout(boolean changed, int l, int t, int r, int b) {int left = getPaddingLeft();int top = getPaddingTop();for (int i = 0; i < getChildCount(); i++) {View child = getChildAt(i);if (i == 0) {//当是header的时候居中显示int headerLeft = getMeasuredWidth() / 2 - child.getMeasuredWidth() / 2;child.layout(headerLeft, top, headerLeft + child.getMeasuredWidth(), top + child.getMeasuredHeight());} elsechild.layout(left, top, left + child.getMeasuredWidth(), top + child.getMeasuredHeight());top += child.getMeasuredHeight();}mHeadviewHeight = getPaddingTop() + mHeaderView.getMeasuredHeight();scrollTo(0, mHeadviewHeight);//移动到header下方以显示recyleviewmFristScollerY = getScrollY();}/*** RecyclerView的滑动监听事件*/RecyclerView.OnScrollListener onScrollListener = new RecyclerView.OnScrollListener() {@Overridepublic void onScrollStateChanged(RecyclerView recyclerView, int newState) {super.onScrollStateChanged(recyclerView, newState);if (newState == RecyclerView.SCROLL_STATE_IDLE) {//滑动到了顶部if (mFirstVisibleItem == 0) {mIsTop = true;} else {mIsTop = false;if (mStatus != STATUS_LOAD && mShowFootVisible && mLastVisibleItem + 1 == mAdapter.getItemCount()) {if (mCurrentPage == mMaxPage) {//当前页面是最后一页的时候mFootViewTips = (TextView) mAdapter.getFootView().findViewById(R.id.footer_tips);mFootViewTips.setText(context.getString(R.string.last_page_tips));handler.sendEmptyMessageDelayed(MSG_LOAD_COMPLETE, DELAY_LOAD_COMPLETE);} else {mStatus = STATUS_LOAD;if (mRecyclerChangeListener != null) {mRecyclerChangeListener.onLoadMore();mCurrentPage++;}}}}}}@Overridepublic void onScrolled(RecyclerView recyclerView, int dx, int dy) {super.onScrolled(recyclerView, dx, dy);if (mLayoutManager instanceof LinearLayoutManager) {mLastVisibleItem = ((LinearLayoutManager) mLayoutManager).findLastVisibleItemPosition();mFirstVisibleItem = ((LinearLayoutManager) mLayoutManager).findFirstCompletelyVisibleItemPosition();setFootviewVisible();} else if (mLayoutManager instanceof GridLayoutManager) {mLastVisibleItem = ((GridLayoutManager) mLayoutManager).findLastVisibleItemPosition();mFirstVisibleItem = ((GridLayoutManager) mLayoutManager).findFirstCompletelyVisibleItemPosition();setFootviewVisible();} else if (mLayoutManager instanceof StaggeredGridLayoutManager) {//因为StaggeredGridLayoutManager的特殊性可能导致最后显示的item存在多个，所以这里取到的是一个数组//得到这个数组后再取到数组中position值最大的那个就是最后显示的position值了int[] lastPositions = new int[((StaggeredGridLayoutManager) mLayoutManager).getSpanCount()];((StaggeredGridLayoutManager) mLayoutManager).findLastVisibleItemPositions(lastPositions);mLastVisibleItem = findMax(lastPositions);mFirstVisibleItem = ((StaggeredGridLayoutManager) mLayoutManager).findFirstVisibleItemPositions(lastPositions)[0];setFootviewVisible();}}};void setFootviewVisible() {//当设置了拥有上拉加载功能但是第一页的条目不足以盛满Recyclerview的时候隐藏footerif (mHasFooter && mFirstVisibleItem == 0) {/*** 这里加上一个mShowFootVisible在上拉加载功能启用的情况下生效，从来控制item数量不足铺满* recyclerview高度的时刻隐藏footview，在item数量超过view高度的情况下显示*/if (mLastVisibleItem + 1 == mAdapter.getItemCount()) {mShowFootVisible = false;} else mShowFootVisible = true;notifyDataSetChanged();}}private int findMax(int[] positions) {int max = positions[0];for (int value : positions) {if (value > max) {max = value;}}return max;}private class AdapterWrapper extends RecyclerView.Adapter {private static final int TYPE_ITEM = 0;private static final int TYPE_FOOTER = 1;private RecyclerView.Adapter mAdapter;private Context mContext;View footer;public AdapterWrapper(Context context, RecyclerView.Adapter wrappedAdapter) {this.mContext = context;this.mAdapter = wrappedAdapter;}@Overridepublic RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {RecyclerView.ViewHolder holder = null;switch (viewType) {case TYPE_ITEM:holder = mAdapter.onCreateViewHolder(parent, viewType);break;case TYPE_FOOTER:footer = LayoutInflater.from(mContext).inflate(R.layout.lib_recyle_footview, null);LinearLayout linearLayout= (LinearLayout) footer.findViewById(R.id.loading_layout);StaggeredGridLayoutManager.LayoutParams layoutParams =new StaggeredGridLayoutManager.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,ViewGroup.LayoutParams.WRAP_CONTENT);layoutParams.setFullSpan(true);linearLayout.setLayoutParams(layoutParams);holder = new FooterViewHolder(footer);break;}return holder;}public View getFootView() {return footer;}@Overridepublic void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {if (!mHasFooter || position + 1 != getItemCount()) {mAdapter.onBindViewHolder(holder, position);}}@Overridepublic int getItemCount() {return mShowFootVisible ? mAdapter.getItemCount() + 1 : mAdapter.getItemCount();}@Overridepublic int getItemViewType(int position) {if (mShowFootVisible && position + 1 == getItemCount()) {return TYPE_FOOTER;} else {return TYPE_ITEM;}}private class FooterViewHolder extends RecyclerView.ViewHolder {public ProgressBar progressBar;public TextView tvLoading;public LinearLayout llyLoading;public FooterViewHolder(View itemView) {super(itemView);progressBar = (ProgressBar) itemView.findViewById(R.id.progress_loading);tvLoading = (TextView) itemView.findViewById(R.id.footer_tips);llyLoading = (LinearLayout) itemView.findViewById(R.id.loading_layout);}}}}

package com.krain.srecyclerview.srecyclerview;import android.support.v7.widget.RecyclerView;import android.view.View;import android.view.ViewGroup;public abstract class BaseRecyclerViewAdapter<VH extends RecyclerView.ViewHolder> extends RecyclerView.Adapter<VH> {private OnItemClickLisener mItemListener;@Overridepublic VH onCreateViewHolder(ViewGroup parent, int viewType) {View view = getItemView(viewType, parent);VH vh = getViewHolder(view);view.setOnClickListener(new OnRecyclerAdapterclickListener(vh, viewType));view.setOnLongClickListener(new OnRecyclerAdapterclickListener(vh, viewType));return vh;}public abstract VH getViewHolder(View itemView);/*** 返回item的view** @return*/public abstract View getItemView(int viewType, ViewGroup parent);/*** 返回Adapter每个itemn的数据 可选*/public Object getItem(int position) {return null;}/*** item点击事件接口** @param mItemListener*/public void setOnItemListener(OnItemClickLisener mItemListener) {this.mItemListener = mItemListener;}@Overridepublic abstract void onBindViewHolder(VH holder, int position);@Overridepublic abstract int getItemCount();class OnRecyclerAdapterclickListener implements View.OnClickListener, View.OnLongClickListener {VH viewholder;int viewType;public OnRecyclerAdapterclickListener(VH viewholder, int viewType) {this.viewholder = viewholder;this.viewType = viewType;}@Overridepublic void onClick(View v) {if (mItemListener != null && viewholder.getAdapterPosition() != RecyclerView.NO_POSITION) {mItemListener.onItemClick(viewholder.getAdapterPosition(), viewType, viewholder, v);}}@Overridepublic boolean onLongClick(View v) {if (mItemListener != null && viewholder.getAdapterPosition() != RecyclerView.NO_POSITION) {mItemListener.onItemLongClick(viewholder.getAdapterPosition(), viewType, viewholder, v);}return false;}}}

void addChildView(Context contex) {ViewGroup.LayoutParams params = new ViewGroup.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);mHeaderView = new ElizabethView(context);mRecyclerView = new RecyclerView(context);addView(mHeaderView);addView(mRecyclerView);//mLayoutManager = new LinearLayoutManager(context);mLayoutManager = new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.VERTICAL);mRecyclerView.setLayoutManager(mLayoutManager);// 设置Item增加、移除默认动画mRecyclerView.setItemAnimator(new DefaultItemAnimator());mRecyclerView.addOnScrollListener(onScrollListener);mRecyclerView.setHasFixedSize(true);mRecyclerView.setLayoutParams(params);}

if (mLayoutManager instanceof StaggeredGridLayoutManager) {//因为StaggeredGridLayoutManager的特殊性可能导致最后显示的item存在多个，所以这里取到的是一个数组//得到这个数组后再取到数组中position值最大的那个就是最后显示的position值了int[] lastPositions = new int[((StaggeredGridLayoutManager) mLayoutManager).getSpanCount()];((StaggeredGridLayoutManager) mLayoutManager).findLastVisibleItemPositions(lastPositions);mLastVisibleItem = findMax(lastPositions);mFirstVisibleItem = ((StaggeredGridLayoutManager) mLayoutManager).findFirstVisibleItemPositions(lastPositions)[0];setFootviewVisible();}