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);
}
@override
protected 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getscrolly
boolean 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);
}
@override
public 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;
@override
public 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;
@override
public 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only
if (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() {
@override
public 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();
}
@override
protected 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);
}
@override
protected 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());
} else
child.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recyleview
mfristscollery = getscrolly();
}
/**
* recyclerview的滑动监听事件
*/
recyclerview.onscrolllistener onscrolllistener = new recyclerview.onscrolllistener() {
@override
public 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++;
}
}
}
}
}
}
@override
public 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footer
if (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;
}
@override
public 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;
}
@override
public void onbindviewholder(recyclerview.viewholder holder, int position) {
if (!mhasfooter || position + 1 != getitemcount()) {
madapter.onbindviewholder(holder, position);
}
}
@override
public int getitemcount() {
return mshowfootvisible ? madapter.getitemcount() + 1 : madapter.getitemcount();
}
@override
public 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;
@override
public 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;
}
@override
public abstract void onbindviewholder(vh holder, int position);
@override
public 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;
}
@override
public void onclick(view v) {
if (mitemlistener != null && viewholder.getadapterposition() != recyclerview.no_position) {
mitemlistener.onitemclick(viewholder.getadapterposition(), viewtype, viewholder, v);
}
}
@override
public 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();
}