Android仿XListView支持下拉刷新和上划加载更多的自定义RecyclerView
程序员文章站
2024-03-31 16:31:52
首先给大家展示下效果图，感觉还不错，请继续往下阅读：
下拉刷新：
上划加载
&nbs...
首先给大家展示下效果图，感觉还不错，请继续往下阅读：
下拉刷新：
上划加载
在项目更新的过程中，遇到了一个将xlistview换成recyclerview的需求，而且更换完之后大体效果不能变，但是对于下拉刷新这样的效果，谷歌给出的解决方案是把recyclerview放在一个swiperefreshlayout中，但是这样其实是拉下一个小圆形控件实现的，和xlistview的header效果不同。在网上找了很多的别人代码，都没有实现我想要的效果，于是自己动手写了一个。
具体实现的效果有以下几条
下拉刷新功能：
1、实现一个有弹性的拖出效果：思路参考xlistview，recyclerview的position=0的位置放一个header布局，这个布局的margin top默认为负的布局高度，所以这块布局就一直处于屏幕外部，在下拉的时候通过ontouchlistener根据手指的移动动态修改margin top，慢慢的拖出，当拖出的距离也就是margin top变为正数以后，就盖面header布局的状态，改变箭头的方向并改变提示语
2、实现有弹性的回弹效果：用timertask写了一个动态修改的header布局的margin top的动画，每隔一定的时间减小margin top的值，当用户松手的时候通过一个函数updateheaderheight（）来执行这个动画。
3、实现用户非手动拖拉的自动刷新效果：这个recyclerview还有一个方法叫forcerefresh（），就是不需要用户手动下拉，头部自己滚动出来，然后刷新完再自己收回去，自动下拉也是用一个timertask每隔十几毫秒增加margin top的值让头部慢慢露出来
上划加载更多功能：
1、实现滚动到底部自动停住效果： 有时候recyclerview滚动太快，滚到底部的时候会根据惯性向上飘，这个地方到底的时候监控recyclerview滚动速度，如果非常快说明是惯性滚动，就不修改footer布局的高度
2、实现向上拖动效果：复写了recyclerview的onscrolllistener，在手指向上滚动的时候，通过updatefooterheight（）方法动态修改底部footerview的margin bottom，同headerview一样，在手指移动的时候让这个margin跟着变大，以增加footer布局的高度，而且手指移动的越网上，增加的margin的高度就越小，实现一个有弹性的上拉效果，防止误操作。
3、实现自动回弹的效果：通过监控footer布局的margin bottom来确定松手的时候是否需要开始刷新，如果margin bottom大于某个值得时候就修改footer布局的状态从normal变成ready，在ready状态下松手就开始刷新操作，回弹也像header布局一样通过一个timertask每隔十几毫秒修改margin的大小来实现回弹效果
注意事项：
1、为了实现头部和底部的代码分离，头部用的是ontouchlistener，底部用的是onscrolllistener
2、本recyclerview里面已经内置了一个layoutmanager,所以不要给recyclerview再设置layoutmanager,否则会出现头部不出来，下拉报空指针的情况，底部出现但是滑动没有效果
3、这个recyclerview内置了一个抽象类作为adapter，请继承这个内置的alxdragrecyclerviewadapter使用，或者按照这里面的逻辑重新写adapter
有其他的问题欢迎问我
4、一些常用的功能，比如设置该控件是否能够支持下拉加载和上拉刷新，等等api接口，请直接参考xlistview的用法即可
使用方法：
继承alxdragrecyclerviewadapter写一个adapter，然后写两个类分别实现onrefreshlistener和loadmorelistener，把具体的刷新逻辑写在里面，在准备好显示数据后调用adapter的notifydatasetchanged（）方法或notifyiteminserted（）方法，并执行该recyclerview的stoploadmore（）方法和stoprefresh（）方法。
下面是代码，这个控件有很多的内部类，包括头部，底部的布局控件（customdragheaderview，customdragfooterview），adapter，layoutmanager都已经以内部类的方式集成在里面，减少迁移时候的复杂度
import android.content.context;
import android.graphics.color;
import android.os.handler;
import android.support.v7.widget.linearlayoutmanager;
import android.support.v7.widget.recyclerview;
import android.util.attributeset;
import android.util.log;
import android.view.layoutinflater;
import android.view.motionevent;
import android.view.view;
import android.view.viewgroup;
import android.view.windowmanager;
import android.view.animation.animation;
import android.view.animation.rotateanimation;
import android.widget.imageview;
import android.widget.linearlayout;
import android.widget.textview;
import com.xxx.app.r;
import java.util.list;
import java.util.timer;
import java.util.timertask;
/**
* created by alex on 2016/1/27.
*/
public class alxrefreshloadmorerecyclerview extends recyclerview {
private int footerheight = -1;
linearlayoutmanager layoutmanager;
// -- footer view
private customdragrecyclerfooterview mfooterview;
private boolean menablepullload;
private boolean mpullloading;
private boolean isbottom;
private boolean misfooterready = false;
private loadmorelistener loadmorelistener;
// -- header view
private customdragheaderview mheaderview;
private boolean menablepullrefresh = true;
private boolean misrefreshing;
private boolean isheader;
private boolean misheaderready = false;
private timer timer;
private float oldy;
handler handler = new handler();
private onrefreshlistener refreshlistener;
private alxdragrecyclerviewadapter adapter;
private int maxpullheight = 50;//最多下拉高度的px值
private static final int header_height = 68;//头部高度68dp
private static final int max_pull_length = 150;//最多下拉150dp
private onclicklistener footerclicklistener;
public alxrefreshloadmorerecyclerview(context context) {
super(context);
initview(context);
}
public alxrefreshloadmorerecyclerview(context context, attributeset attrs) {
super(context, attrs);
initview(context);
}
public alxrefreshloadmorerecyclerview(context context, attributeset attrs, int defstyle) {
super(context, attrs, defstyle);
initview(context);
}
public void setadapter(alxdragrecyclerviewadapter adapter){
super.setadapter(adapter);
this.adapter = adapter;
}
public boolean ismpullloading() {
return mpullloading;
}
public boolean ismisrefreshing() {
return misrefreshing;
}
private void updatefooterheight(float delta) {
if(mfooterview==null)return;
int bottommargin = mfooterview.getbottommargin();
// log.i("alex3","初始delta是"+delta);
if(delta>50)delta = delta/6;
if(delta>0) {//越往下滑越难滑
if(bottommargin>maxpullheight)delta = delta*0.65f;
else if(bottommargin>maxpullheight * 0.83333f)delta = delta*0.7f;
else if(bottommargin>maxpullheight * 0.66667f)delta = delta*0.75f;
else if(bottommargin>maxpullheight >> 1)delta = delta*0.8f;
else if(bottommargin>maxpullheight * 0.33333f)delta = delta*0.85f;
else if(bottommargin>maxpullheight * 0.16667f && delta > 20)delta = delta*0.2f;//如果是因为惯性向下迅速的俯冲
else if(bottommargin>maxpullheight * 0.16667f)delta = delta*0.9f;
// log.i("alex3","bottommargin是"+mfooterview.getbottommargin()+" delta是"+delta);
}
int height = mfooterview.getbottommargin() + (int) (delta+0.5);
if (menablepullload && !mpullloading) {
if (height > 150){//必须拉超过一定距离才加载更多
// if (height > 1){//立即刷新
mfooterview.setstate(customdragrecyclerfooterview.state_ready);
misfooterready = true;
// log.i("alex2", "ready");
} else {
mfooterview.setstate(customdragrecyclerfooterview.state_normal);
misfooterready = false;
// log.i("alex2", "nomal");
}
}
mfooterview.setbottommargin(height);
}
private void resetfooterheight() {
int bottommargin = mfooterview.getbottommargin();
if (bottommargin > 20) {
log.i("alex2", "准备重置高度,margin是" + bottommargin + "自高是" + footerheight);
this.smoothscrollby(0,-bottommargin);
//一松手就立即开始加载
if(misfooterready){
startloadmore();
}
}
}
public void setloadmorelistener(loadmorelistener listener){
this.loadmorelistener = listener;
}
public void initview(context context){
layoutmanager = new linearlayoutmanager(context);//自带layoutmanager，请勿设置
layoutmanager.setorientation(linearlayoutmanager.vertical);
windowmanager wm = (windowmanager) getcontext().getsystemservice(context.window_service);
int height = wm.getdefaultdisplay().getheight();
layoutmanager.offsetchildrenvertical(height*2);//预加载2/3的卡片
this.setlayoutmanager(layoutmanager);
// log.i("alex", "屏幕密度为" + getcontext().getresources().getdisplaymetrics().density);
maxpullheight = dp2px(getcontext().getresources().getdisplaymetrics().density,max_pull_length);//最多下拉150dp
this.footerclicklistener = new footerviewclicklistener();
this.addonscrolllistener(new recyclerview.onscrolllistener() {
@override
public void onscrollstatechanged(recyclerview recyclerview, int newstate) {
super.onscrollstatechanged(recyclerview, newstate);
switch (newstate){
case recyclerview.scroll_state_idle:
// log.i("alex2", "停下了||放手了");
if(isbottom)resetfooterheight();
break;
case recyclerview.scroll_state_dragging:
// log.i("alex2", "开始拖了,现在margin是" + (mfooterview == null ? "" : mfooterview.getbottommargin()));
break;
case recyclerview.scroll_state_settling:
// log.i("alex2", "开始惯性移动");
break;
}
}
@override
public void onscrolled(recyclerview recyclerview, int dx, int dy) {
super.onscrolled(recyclerview, dx, dy);
int lastitemposition = layoutmanager.findlastvisibleitemposition();
// log.i("alex2","menable是"+menablepullload+"lastitemposition是"+lastitemposition+" itemcount是"+layoutmanager.getitemcount());
if(lastitemposition == layoutmanager.getitemcount()-1 && menablepullload) {//如果到了最后一个
isbottom = true;
mfooterview = (customdragrecyclerfooterview)layoutmanager.findviewbyposition(layoutmanager.findlastvisibleitemposition());//一开始还不能hide，因为hide得到最后一个可见的就不是footerview了
// log.i("alex2","到底啦！！"+"mfooterview是"+mfooterview);
if(mfooterview!=null) mfooterview.setonclicklistener(footerclicklistener);
if(footerheight==-1 && mfooterview!=null){
mfooterview.show();
mfooterview.setstate(customdragrecyclerfooterview.state_normal);
footerheight = mfooterview.getmeasuredheight();//这里的测量一般不会出问题
// log.i("alex2", "底部高度为" + footerheight);
}
updatefooterheight(dy);
}else if(lastitemposition == layoutmanager.getitemcount()-1 && menablepullload){//如果到了倒数第二个
startloadmore();//开始加载更多
}
else {
isbottom = false;
}
}
});
}
/**
* 设置是否开启上拉加载更多的功能
*
* @param enable
*/
public void setpullloadenable(boolean enable) {
mpullloading = false;
menablepullload = enable;
if(adapter!=null)adapter.setpullloadmoreenable(enable);//adapter和recyclerview要同时设置
if(mfooterview==null)return;
if (!menablepullload) {
// this.smoothscrollby(0,-footerheight);
mfooterview.hide();
mfooterview.setonclicklistener(null);
mfooterview.setbottommargin(0);
//make sure "pull up" don't show a line in bottom when listview with one page
} else {
mfooterview.show();
mfooterview.setstate(customdragrecyclerfooterview.state_normal);
mfooterview.setvisibility(visible);
//make sure "pull up" don't show a line in bottom when listview with one page
// both "pull up" and "click" will invoke load more.
mfooterview.setonclicklistener(new onclicklistener() {
@override
public void onclick(view v) {
startloadmore();
}
});
}
}
/**
* 停止loadmore
*/
public void stoploadmore() {
if (mpullloading == true) {
mpullloading = false;
if(mfooterview==null)return;
mfooterview.show();
mfooterview.setstate(customdragrecyclerfooterview.state_error);
}
}
private void startloadmore() {
if(mpullloading)return;
mpullloading = true;
if(mfooterview!=null)mfooterview.setstate(customdragrecyclerfooterview.state_loading);
log.i("alex2", "现在开始加载");
misfooterready = false;
if (loadmorelistener != null) {
loadmorelistener.onloadmore();
}
}
/**
* 在刷新时要执行的方法
*/
public interface loadmorelistener{
public void onloadmore();
}
/**
* 点击loadmore后要执行的事件
*/
class footerviewclicklistener implements onclicklistener {
@override
public void onclick(view v) {
startloadmore();
}
}
private void updateheaderheight(float delta) {
mheaderview = (customdragheaderview) layoutmanager.findviewbyposition(0);
// log.i("alex2", "现在在头部！！！！ header自高是" + mheaderview.getheight() + " margin 是" + mheaderview.gettopmargin());//自高一般不会算错
// log.i("alex2", "正在设置margin" + mheaderview.gettopmargin() +"delta是"+delta);
if(delta>0){//如果是往下拉
int topmargin = mheaderview.gettopmargin();
if(topmargin>maxpullheight * 0.33333f)delta = delta*0.5f;
else if(topmargin>maxpullheight * 0.16667f)delta = delta*0.55f;
else if(topmargin>0)delta = delta*0.6f;
else if(topmargin<0)delta = delta*0.6f;//如果没有被完全拖出来
mheaderview.settopmargin(mheaderview.gettopmargin() + (int)delta);
} else{//如果是推回去
if(!misrefreshing || mheaderview.gettopmargin()>0) {//在刷新的时候不把margin设为负值以在惯性滑动的时候能滑回去
this.scrollby(0, (int) delta);//禁止既滚动，又同时减少触摸
// log.i("alex2", "正在往回推" + delta);
mheaderview.settopmargin(mheaderview.gettopmargin() + (int) delta);
}
}
if(mheaderview.gettopmargin()>0 && !misrefreshing){
misheaderready = true;
mheaderview.setstate(customdragheaderview.state_ready);
}//设置为ready状态
else if(!misrefreshing){
misheaderready = false;
mheaderview.setstate(customdragheaderview.state_normal);
}//设置为普通状态并且缩回去
}
@override
public void smoothscrolltoposition(final int position) {
super.smoothscrolltoposition(position);
final timer scrolltimer = new timer();
timertask timertask = new timertask() {
@override
public void run() {
int bottomcardposition = layoutmanager.findlastvisibleitemposition();
if(bottomcardposition<position+1){//如果要向下滚
handler.post(new runnable() {
@override
public void run() {
smoothscrollby(0,50);
}
});
}else if(bottomcardposition>position){//如果要向上滚
handler.post(new runnable() {
@override
public void run() {
smoothscrollby(0,-50);
}
});
}else {
if(scrolltimer!=null)scrolltimer.cancel();
}
}
};
scrolltimer.schedule(timertask,0,20);
}
/**
* 在用户非手动强制刷新的时候，通过一个动画把头部一点点冒出来
*/
private void smoothshowheader(){
if(mheaderview==null)return;
// if(layoutmanager.findfirstvisibleitemposition()!=0){//如果刷新完毕的时候用户没有注视header
// mheaderview.settopmargin(0);
// return;
// }
if(timer!=null)timer.cancel();
final timertask timertask = new timertask() {
@override
public void run() {
if(mheaderview==null){
if(timer!=null)timer.cancel();
return;
}
// log.i("alex2","topmargin是"+mheaderview.gettopmargin()+" height是"+mheaderview.getheight());
if(mheaderview.gettopmargin()<0){
handler.post(new runnable() {
@override
public void run() {
if (misrefreshing) {//如果目前是ready状态或者正在刷新状态
mheaderview.settopmargin(mheaderview.gettopmargin() +2);
}
}
});
} else if(timer!=null){//如果已经完全缩回去了，但是动画还没有结束，就结束掉动画
timer.cancel();
}
}
};
timer = new timer();
timer.scheduleatfixedrate(timertask,0,16);
}
/**
* 在用户松手的时候让头部自动收缩回去
*/
private void resetheaderheight() {
if(mheaderview==null)mheaderview = (customdragheaderview) layoutmanager.findviewbyposition(0);
if(layoutmanager.findfirstvisibleitemposition()!=0){//如果刷新完毕的时候用户没有注视header
mheaderview.settopmargin(-mheaderview.getrealheight());
return;
}
if(timer!=null)timer.cancel();
final timertask timertask = new timertask() {
@override
public void run() {
if(mheaderview==null)return;
// log.i("alex2","topmargin是"+mheaderview.gettopmargin()+" height是"+mheaderview.getheight());
if(mheaderview.gettopmargin()>-mheaderview.getrealheight()){//如果header没有完全缩回去
handler.post(new runnable() {
@override
public void run() {
if (misheaderready || misrefreshing) {//如果目前是ready状态或者正在刷新状态
// log.i("alex2", "现在是ready状态");
int delta = mheaderview.gettopmargin() / 9;
if (delta < 5) delta = 5;
if (mheaderview.gettopmargin() > 0)
mheaderview.settopmargin(mheaderview.gettopmargin() - delta);
} else {//如果是普通状态
// log.i("alex2", "现在是普通状态");
mheaderview.settopmargin(mheaderview.gettopmargin() - 5);
}
}
});
} else if(timer!=null){//如果已经完全缩回去了，但是动画还没有结束，就结束掉动画
timer.cancel();
handler.post(new runnable() {
@override
public void run() {
mheaderview.setstate(mheaderview.state_finish);
}
});
}
}
};
timer = new timer();
timer.scheduleatfixedrate(timertask,0,10);
}
/**
* 头部是通过ontouchevent控制的
* @param event
* @return
*/
@override
public boolean ontouchevent(motionevent event) {
switch (event.getaction()) {
case motionevent.action_move:
int delta = (int)(event.gety()-oldy);
oldy = event.gety();
if (layoutmanager.findviewbyposition(0) instanceof customdragheaderview) {
isheader = true;
updateheaderheight(delta);//更新margin高度
}else{
isheader = false;
if(mheaderview!=null && !misrefreshing)mheaderview.settopmargin(-mheaderview.getrealheight());
}
break;
// case motionevent.action_down:
// log.i("alex", "touch down");
// oldy = event.gety();
// if(timer!=null)timer.cancel();
// break;
case motionevent.action_up:
// log.i("alex", "抬手啦！！！！ touch up ");
if(misheaderready && !misrefreshing)startrefresh();
if(isheader)resetheaderheight();//抬手之后恢复高度
break;
case motionevent.action_cancel:
// log.i("alex", "touch cancel");
break;
}
return super.ontouchevent(event);
}
/**
* 因为设置了子元素的onclicklistener之后，ontouch方法的down失效，所以要在分发前获取手指的位置
* @param ev
* @return
*/
@override
public boolean dispatchtouchevent(motionevent ev) {
// todo auto-generated method stub
switch (ev.getaction()) {
case motionevent.action_down:
// log.i("alex", "touch down分发前");
oldy = ev.gety();
if (timer != null) timer.cancel();
break;
}
return super.dispatchtouchevent(ev);
}
public void setonrefreshlistener(onrefreshlistener listener){
this.refreshlistener = listener;
}
/**
* 设置是否支持下啦刷新的功能
*
* @param enable
*/
public void setpullrefreshenable(boolean enable) {
misrefreshing = false;
menablepullrefresh = enable;
if(mheaderview==null)return;
if (!menablepullrefresh) {
mheaderview.setonclicklistener(null);
} else {
mheaderview.setstate(customdragfooterview.state_normal);
mheaderview.setvisibility(visible);
}
}
/**
* 停止下拉刷新，并且通过动画让头部自己缩回去
*/
public void stoprefresh() {
if (misrefreshing == true) {
misrefreshing = false;
misheaderready = false;
if(mheaderview==null)return;
mheaderview.setstate(customdragfooterview.state_normal);
resetheaderheight();
}
}
/**
* 在用户没有用手控制的情况下，通过动画把头部露出来并且执行刷新
*/
public void forcerefresh(){
if(mheaderview==null)mheaderview = (customdragheaderview) layoutmanager.findviewbyposition(0);
if(mheaderview!=null)mheaderview.setstate(customdragheaderview.state_refreshing);
misrefreshing = true;
log.i("alex2", "现在开始强制刷新");
misheaderready = false;
smoothshowheader();
if (refreshlistener != null)refreshlistener.onrefresh();
}
private void startrefresh() {
misrefreshing = true;
mheaderview.setstate(customdragheaderview.state_refreshing);
log.i("alex2", "现在开始加载");
misheaderready = false;
if (refreshlistener != null) refreshlistener.onrefresh();
}
public interface onrefreshlistener{
public void onrefresh();
}
/**
* 适用于本recycler的头部下拉刷新view
*/
public static class customdragheaderview extends linearlayout {
public final static int state_normal = 0;
public final static int state_ready = 1;
public final static int state_refreshing = 2;
public final static int state_finish = 3;
public float screendensity;
private final int rotate_anim_duration = 180;
private context mcontext;
private view mcontentview;
private view mprogressbar;
private imageview marrowimageview;
private textview mhinttextview;
private animation mrotateupanim;
private animation mrotatedownanim;
public customdragheaderview(context context) {
super(context);
initview(context);
}
public customdragheaderview(context context, attributeset attrs) {
super(context, attrs);
initview(context);
}
private int mstate;
public void setstate(int state) {
if (state == mstate)
return;
if (state == state_refreshing) { // 显示进度
marrowimageview.clearanimation();
marrowimageview.setvisibility(view.invisible);
mprogressbar.setvisibility(view.visible);
} else { // 显示箭头图片
marrowimageview.setvisibility(view.visible);
mprogressbar.setvisibility(view.invisible);
}
switch (state) {
case state_normal:
if (mstate == state_ready) {
marrowimageview.startanimation(mrotatedownanim);
mhinttextview.settext(r.string.xlistview_header_hint_normal);
}
else if (mstate == state_refreshing) {//如果是从刷新状态过来
// marrowimageview.clearanimation();
marrowimageview.setvisibility(invisible);
mhinttextview.settext("load completed");
}
break;
case state_ready:
if (mstate != state_ready) {
marrowimageview.clearanimation();
marrowimageview.startanimation(mrotateupanim);
}
mhinttextview.settext(r.string.xlistview_header_hint_ready);
break;
case state_refreshing:
mhinttextview.settext(r.string.xlistview_header_hint_loading);
break;
case state_finish:
marrowimageview.setvisibility(view.visible);
mhinttextview.settext(r.string.xlistview_header_hint_normal);
break;
default:
}
mstate = state;
}
public void settopmargin(int height) {
if (mcontentview==null) return ;
layoutparams lp = (layoutparams)mcontentview.getlayoutparams();
lp.topmargin = height;
mcontentview.setlayoutparams(lp);
}
//
public int gettopmargin() {
layoutparams lp = (layoutparams)mcontentview.getlayoutparams();
return lp.topmargin;
}
public void setheight(int height){
if (mcontentview==null) return ;
layoutparams lp = (layoutparams)mcontentview.getlayoutparams();
lp.height = height;
mcontentview.setlayoutparams(lp);
}
private int realheight;
/**
* 得到这个headerview真实的高度，而且这个高度是自己定的
* @return
*/
public int getrealheight(){
return realheight;
}
private void initview(context context) {
mcontext = context;
this.setlayoutparams(new layoutparams(layoutparams.match_parent, layoutparams.wrap_content));//recyclerview里不加这句话的话宽度就会比较窄
linearlayout moreview = (linearlayout) layoutinflater.from(mcontext).inflate(r.layout.xlistview_header, null);
addview(moreview);
moreview.setlayoutparams(new layoutparams(layoutparams.match_parent, layoutparams.wrap_content));
mcontentview = moreview.findviewbyid(r.id.xlistview_header_content);
layoutparams lp = (layoutparams)mcontentview.getlayoutparams();
log.i("alex", "初始height是" + mcontentview.getheight());
lp.height = 150;//手动设置高度,如果要手动加载更多的时候才设置
screendensity = getcontext().getresources().getdisplaymetrics().density;//设置屏幕密度，用来px向dp转化
lp.height = dp2px(screendensity,header_height);//头部高度75dp
realheight = lp.height;
lp.topmargin = -lp.height;
mcontentview.setlayoutparams(lp);
marrowimageview = (imageview) findviewbyid(r.id.xlistview_header_arrow);
mhinttextview = (textview) findviewbyid(r.id.xlistview_header_hint_textview);
mhinttextview.setpadding(0,dp2px(screendensity,3),0,0);//不知道为什么这个文字总会向上偏一下，所以要补回来
mprogressbar = findviewbyid(r.id.xlistview_header_progressbar);
mrotateupanim = new rotateanimation(0.0f, -180.0f, animation.relative_to_self, 0.5f, animation.relative_to_self, 0.5f);
mrotateupanim.setduration(rotate_anim_duration);
mrotateupanim.setfillafter(true);
mrotatedownanim = new rotateanimation(-180.0f, 0.0f, animation.relative_to_self, 0.5f, animation.relative_to_self, 0.5f);
mrotatedownanim.setduration(rotate_anim_duration);
mrotatedownanim.setfillafter(true);
}
}
public static int dp2px(float density, int dp) {
if (dp == 0) {
return 0;
}
return (int) (dp * density + 0.5f);
}
public static class customdragrecyclerfooterview extends linearlayout {
public final static int state_normal = 0;
public final static int state_ready = 1;
public final static int state_loading = 2;
public final static int state_error = 3;
private context mcontext;
private view mcontentview;
private view mprogressbar;
private textview mhintview;
public customdragrecyclerfooterview(context context) {
super(context);
initview(context);
}
public customdragrecyclerfooterview(context context, attributeset attrs) {
super(context, attrs);
initview(context);
}
public void setstate(int state) {
mprogressbar.setvisibility(view.invisible);
// mhintview.setvisibility(view.invisible);
if (state == state_ready) {
mhintview.setvisibility(view.visible);
mhintview.settext("松手加载更多");
} else if (state == state_loading) {
mprogressbar.setvisibility(view.visible);
mhintview.setvisibility(invisible);
} else if(state == state_error){
mprogressbar.setvisibility(gone);
mhintview.setvisibility(visible);
mhintview.settext(r.string.xlistview_footer_hint_ready);
}
else {
mhintview.setvisibility(view.visible);
mhintview.settext(r.string.xlistview_footer_hint_normal);
mhintview.settext("load more");
}
}
public void setbottommargin(int height) {
if (height < 0) return ;
layoutparams lp = (layoutparams)mcontentview.getlayoutparams();
lp.bottommargin = height;
mcontentview.setlayoutparams(lp);
}
public int getbottommargin() {
layoutparams lp = (layoutparams)mcontentview.getlayoutparams();
return lp.bottommargin;
}
/**
* normal status
*/
public void normal() {
mhintview.setvisibility(view.visible);
mprogressbar.setvisibility(view.gone);
}
/**
* loading status
*/
public void loading() {
mhintview.setvisibility(view.gone);
mprogressbar.setvisibility(view.visible);
}
/**
* hide footer when disable pull load more
*/
public void hide() {
layoutparams lp = (layoutparams)mcontentview.getlayoutparams();
lp.height = 1;//这里如果设为0那么layoutmanger就会抓不到
mcontentview.setlayoutparams(lp);
mcontentview.setbackgroundcolor(color.black);//这里的颜色要和自己的背景色一致
}
/**
* show footer
*/
public void show() {
layoutparams lp = (layoutparams)mcontentview.getlayoutparams();
lp.height = layoutparams.wrap_content;
lp.width = layoutparams.match_parent;
mcontentview.setlayoutparams(lp);
mcontentview.setbackgroundcolor(color.white);//这里的颜色要和自己的背景色一致
}
private void initview(context context) {
mcontext = context;
this.setlayoutparams(new layoutparams(layoutparams.match_parent, layoutparams.wrap_content));
linearlayout moreview = (linearlayout) layoutinflater.from(mcontext).inflate(r.layout.layout_customdragfooterview, null);
addview(moreview);
moreview.setlayoutparams(new layoutparams(layoutparams.match_parent, layoutparams.wrap_content));
mcontentview = moreview.findviewbyid(r.id.rlcontentview);
mprogressbar = moreview.findviewbyid(r.id.pbcontentview);
mhintview = (textview)moreview.findviewbyid(r.id.ctvcontentview);
mhintview.settext("load more");
// mprogressbar.setvisibility(visible);//一直会显示转圈，自动加载更多时使用
}
}
/**
* 为了防止代码上的混乱，使用这个recyclerview自己内置的一个adapter
* @param <t>
*/
public static abstract class alxdragrecyclerviewadapter<t> extends recyclerview.adapter<recyclerview.viewholder>{
protected static final int type_header = 436874;
protected static final int type_item = 256478;
protected static final int type_footer = 9621147;
private int item;
private viewholder vhitem;
protected boolean loadmore;
private list<t> datalist;
public list<t> getdatalist() {
return datalist;
}
public void setdatalist(list<t> datalist) {
this.datalist = datalist;
}
public alxdragrecyclerviewadapter(list<t> datalist,int itemlayout,boolean pullenable){
this.datalist = datalist;
this.item = itemlayout;
this.loadmore = pullenable;
}
public abstract viewholder setitemviewholder(view itemview);
private t getobject(int position){
if(datalist!=null && datalist.size()>=position)return datalist.get(position-1);//如果有header
return null;
}
@override
public recyclerview.viewholder oncreateviewholder(viewgroup parent, int viewtype) {
if (viewtype == type_item) {
//inflate your layout and pass it to view holder
view itemview = layoutinflater.from(parent.getcontext()).inflate(item,null);
log.i("alex","itemview是"+itemview);
this.vhitem = setitemviewholder(itemview);
log.i("alex","vhitem是"+vhitem);
return vhitem;
} else if (viewtype == type_header) {
//inflate your layout and pass it to view holder
view headerview = new customdragheaderview(parent.getcontext());
return new vhheader(headerview);
} else if(viewtype==type_footer){
customdragrecyclerfooterview footerview = new customdragrecyclerfooterview(parent.getcontext());
return new vhfooter(footerview);
}
throw new runtimeexception("there is no type that matches the type " + viewtype + " + make sure your using types correctly");
}
public void setpullloadmoreenable(boolean enable){
this.loadmore = enable;
}
public boolean getpullloadmoreenable(){return loadmore;}
@override
public void onbindviewholder(recyclerview.viewholder holder, int position) {//相当于getview
log.i("alex","正在绑定"+position+" "+holder.getclass());
if (vhitem!=null && holder.getclass() == vhitem.getclass()) {
//cast holder to vhitem and set data
inititemview(holder,position,getobject(position));
}else if (holder instanceof alxdragrecyclerviewadapter.vhheader) {
//cast holder to vhheader and set data for header.
}else if(holder instanceof alxdragrecyclerviewadapter.vhfooter){
if(!loadmore)((vhfooter)holder).footerview.hide();//第一次初始化显示的时候要不要显示footerview
}
}
@override
public int getitemcount() {
return (datalist==null ||datalist.size()==0)?1:datalist.size() + 2;//如果有header,若list不存在或大小为0就没有footview，反之则有
}//这里要考虑到头尾部，多以要加2
/**
* 根据位置判断这里该用哪个viewholder
* @param position
* @return
*/
@override
public int getitemviewtype(int position) {
if (position == 0)return type_header;
else if(ispositonfooter(position))return type_footer;
return type_item;
}
protected boolean ispositonfooter(int position){//这里的position从0算起
if (datalist == null && position == 1) return true;//如果没有item
return position == datalist.size() + 1;//如果有item(也许为0)
}
// class vhitem extends recyclerview.viewholder {
// public vhitem(view itemview) {
// super(itemview);
// }
// public view getitemview(){return itemview;}
// }
//
protected class vhheader extends recyclerview.viewholder {
public vhheader(view headerview) {
super(headerview);
}
}
protected class vhfooter extends recyclerview.viewholder {
public customdragrecyclerfooterview footerview;
public vhfooter(view itemview) {
super(itemview);
footerview = (customdragrecyclerfooterview)itemview;
}
}
public abstract void inititemview(viewholder itemholder,int posion,t entity);
}
}
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