再也不用担心下拉刷新，上拉加载啦！-自定义ListView对上拉刷新，上拉加载的详解

/**
*下拉刷新接口
*/
publicinterfaceRLoadListener{
publicvoidonRefresh();

}

publicvoidsetReflashInterface(RLoadListenerrLoadListener){
this.rLoadListener=rLoadListener;

}

/**
*获取完整数据
*
*/
publicvoidreflashComplete(){
state=NONE;
isRemark=false;
reflashViewByState();
TextViewlasetupdate_time=(TextView)header.findViewById(R.id.tv_lastupdate_time);
SimpleDateFormatsimpleDateFormat=newSimpleDateFormat("yyyy年MM月dd日hh:mm:ss");
Datedate=newDate(System.currentTimeMillis());
Stringtime=simpleDateFormat.format(date);
lasetupdate_time.setText(time);

}

<?xmlversion="1.0"encoding="utf-8"?>
<LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_centerInParent="true"
android:orientation="vertical">

<LinearLayout
android:id="@+id/ll_footer"
android:layout_width="match_parent"
android:layout_height="wrap_content"

android:orientation="vertical">
<ProgressBar
android:id="@+id/footer_pb"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
style="?android:attr/progressBarStyleSmall"
android:layout_gravity="center"
/>
<TextView
android:id="@+id/footer_tv"
android:text="footer正在加载。。"
android:textSize="16sp"

android:gravity="center"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>

</LinearLayout>

</LinearLayout>

<?xmlversion="1.0"encoding="utf-8"?>
<LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingTop="10dip"
android:paddingBottom="10dip"
>
<LinearLayout
android:id="@+id/ll_header"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:gravity="center"
android:orientation="vertical">
<TextView
android:id="@+id/tip"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="下拉可以刷新"/>
<TextView
android:id="@+id/tv_lastupdate_time"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>

</LinearLayout>

<ImageView
android:id="@+id/arrow"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toLeftOf="@id/ll_header"
android:layout_marginRight="20dip"
android:src="@drawable/pull_down_refresh_arrow"

/>
<ProgressBar
android:id="@+id/header_pb"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
style="?android:attr/progressBarStyleSmall"
android:layout_toLeftOf="@id/ll_header"
android:layout_marginRight="20dip"
android:visibility="gone"/>

</RelativeLayout>

</LinearLayout>

<?xmlversion="1.0"encoding="utf-8"?>
<LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingTop="10dip"
android:paddingBottom="10dip"
>
<LinearLayout
android:id="@+id/ll_header"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:gravity="center"
android:orientation="vertical">
<TextView
android:id="@+id/tip"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="下拉可以刷新"/>
<TextView
android:id="@+id/tv_lastupdate_time"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>

</LinearLayout>

<ImageView
android:id="@+id/arrow"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toLeftOf="@id/ll_header"
android:layout_marginRight="20dip"
android:src="@drawable/pull_down_refresh_arrow"

/>
<ProgressBar
android:id="@+id/header_pb"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
style="?android:attr/progressBarStyleSmall"
android:layout_toLeftOf="@id/ll_header"
android:layout_marginRight="20dip"
android:visibility="gone"/>

</RelativeLayout>

</LinearLayout>

<RelativeLayoutxmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"android:layout_width="match_parent"
android:layout_height="match_parent"android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"tools:context=".MainActivity">
<com.example.administrator.listviewtest.LoadListView
android:id="@+id/lv_main"
android:layout_width="match_parent"
android:layout_height="match_parent"></com.example.administrator.listviewtest.LoadListView>
</RelativeLayout>

packagecom.example.administrator.listviewtest;

importandroid.content.Context;
importandroid.util.AttributeSet;
importandroid.view.LayoutInflater;
importandroid.view.MotionEvent;
importandroid.view.View;
importandroid.view.ViewGroup;
importandroid.view.animation.RotateAnimation;
importandroid.widget.AbsListView;
importandroid.widget.ImageView;
importandroid.widget.ListView;
importandroid.widget.ProgressBar;
importandroid.widget.TextView;

importjava.text.SimpleDateFormat;
importjava.util.Date;

/**
*CreatedbyAdministratoron2015-10-12.
*/
publicclassLoadListViewextendsListViewimplementsAbsListView.OnScrollListener{
privateintlastVisibleItem;//最后一个可见项
privateinttotalItems;//总的item
privateViewfooter,header;//底部View+头部View;
privatebooleanisLoading=false;//是否正在加载
privateILoadListeneriListener;//自定义的一个加载接口。暴露给MainActivity让它实现具体加载操作。可以根据需求不同而改写。

privatebooleanisRemark=false;//判断是否在当前页的最顶端并下滑
privateintstartY;//Y坐标记录手指开始按下的坐标
privateRLoadListenerrLoadListener;//自定义的一个加载接口。暴露给MainActivity让它实现具体加载操作。可以根据需求不同而改写。

privateintscrollState;//当前滚动的状态

privateintheaderHeight;//顶部布局文件的高度

finalintNONE=0;//正常状态
finalintPULL=1;//下拉
finalintRELESE=2;//释放
finalintREFLASHING=3;//刷新

privateintstate=0;//判断当前状态,默认为正常状态

privateintfirstVisibleItem;//第一个可见项

publicLoadListView(Contextcontext){
this(context,null);

}

publicLoadListView(Contextcontext,AttributeSetattrs){
this(context,attrs,android.R.attr.listViewStyle);

}

publicLoadListView(Contextcontext,AttributeSetattrs,intdefStyleAttr){
super(context,attrs,defStyleAttr);

initViews(context);

}

/**
*添加底部+头部提示到ListVIew
*@paramcontext
*/
privatevoidinitViews(Contextcontext){
//获得footer+header布局文件
LayoutInflaterinflater=LayoutInflater.from(context);
footer=inflater.inflate(R.layout.footer,null);

footer.findViewById(R.id.ll_footer).setVisibility(GONE);//初始化时设置footer不可见

header=inflater.inflate(R.layout.header,null);
//测量header的宽和高
measureView(header);
//记录下header的高
headerHeight=header.getMeasuredHeight();
topPadding(-headerHeight);

this.addHeaderView(header);
this.addFooterView(footer);
this.setOnScrollListener(this);//设置滚动监听

}

/**
*通知父布局，占用的宽和高
*@paramview
*/
privatevoidmeasureView(Viewview){

//得到view的布局宽高
ViewGroup.LayoutParamsvlp=view.getLayoutParams();
//如果没有就new一个
if(vlp==null){
vlp=newViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,ViewGroup.LayoutParams.WRAP_CONTENT);
}
//ViewGroup.getChildMeasureSpec(intspec,intpadding,intchildDimension)1.父view的详细尺寸2.view当前尺寸的下的边距3.child在当前尺寸下的宽（高）
intwidth=ViewGroup.getChildMeasureSpec(0,0,vlp.width);
intheight;
inttempHeight=vlp.height;
if(tempHeight>0){
height=MeasureSpec.makeMeasureSpec(tempHeight,MeasureSpec.EXACTLY);

}else{
height=MeasureSpec.makeMeasureSpec(0,MeasureSpec.UNSPECIFIED);
}
view.measure(width,height);

}

/**
*设置header布局的上边距
*@paramtopPadding
*/
privatevoidtopPadding(inttopPadding){
header.setPadding(header.getPaddingLeft(),topPadding,header.getPaddingRight(),header.getPaddingBottom());
//重绘
header.invalidate();

}

@Override
publicvoidonScrollStateChanged(AbsListViewview,intscrollState){
this.scrollState=scrollState;
if(lastVisibleItem==totalItems&&scrollState==SCROLL_STATE_IDLE){
//如果不是在加载
if(!isLoading){
footer.findViewById(R.id.ll_footer).setVisibility(View.VISIBLE);
iListener.onLoad();
isLoading=true;

}
}

}

@Override
publicvoidonScroll(AbsListViewview,intfirstVisibleItem,intvisibleItemCount,inttotalItemCount){
this.lastVisibleItem=firstVisibleItem+visibleItemCount;
this.totalItems=totalItemCount;
this.firstVisibleItem=firstVisibleItem;
}

/**
*加载更多数据的回调接口
*/
publicinterfaceILoadListener{
publicvoidonLoad();
}
//上拉加载完毕
publicvoidloadCompleted(){
isLoading=false;
footer.findViewById(R.id.ll_footer).setVisibility(GONE);
}

publicvoidsetInterface(ILoadListeneriListener){

this.iListener=iListener;
}
/**
*下拉刷新接口
*/
publicinterfaceRLoadListener{
publicvoidonRefresh();

}

publicvoidsetReflashInterface(RLoadListenerrLoadListener){
this.rLoadListener=rLoadListener;

}

@Override
publicbooleanonTouchEvent(MotionEventev){
switch(ev.getAction()){
caseMotionEvent.ACTION_DOWN://如果按下
if(firstVisibleItem==0){
isRemark=true;
startY=(int)ev.getY();
}
break;
caseMotionEvent.ACTION_MOVE:
onMove(ev);
break;
caseMotionEvent.ACTION_UP:
if(state==RELESE){
state=REFLASHING;
//加载最新数据
reflashViewByState();
rLoadListener.onRefresh();
}elseif(state==PULL){
state=NONE;
isRemark=false;
reflashViewByState();
}
break;

}

returnsuper.onTouchEvent(ev);
}

/**
*判断移动的过程
*
*@paramev
*/
privatevoidonMove(MotionEventev){
if(!isRemark){
return;
}
inttempY=(int)ev.getY();
//记录滑动距离
intspace=tempY-startY;
//比较滑动距离和header的高
inttopPadding=space-headerHeight;
switch(state){
caseNONE:
if(space>0){
state=PULL;
reflashViewByState();
}
break;
casePULL:
//重绘header
topPadding(topPadding);
if(space>headerHeight+30&&scrollState==SCROLL_STATE_TOUCH_SCROLL){
state=RELESE;
reflashViewByState();

}
break;
caseRELESE:
topPadding(topPadding);
if(space<headerHeight+30){
state=PULL;
reflashViewByState();
}elseif(space<=0){//如果space<0说明向上滑。所以firstVisibleItem就不是0了所以将isRemark设置为false;即listView现在不是最顶端的位置
state=NONE;
isRemark=false;
reflashViewByState();
}
break;

}

}

/**
*根据当前状态，改变界面显示
*/
privatevoidreflashViewByState(){
TextViewtip=(TextView)header.findViewById(R.id.tip);
ImageViewarrow=(ImageView)header.findViewById(R.id.arrow);
ProgressBarheader_pb=(ProgressBar)header.findViewById(R.id.header_pb);
//设置的下拉箭头的动画效果
RotateAnimationanimation=newRotateAnimation(0,180,RotateAnimation.RELATIVE_TO_SELF,0.5f,RotateAnimation.RELATIVE_TO_SELF,0.5f);
animation.setDuration(500);
animation.setFillAfter(true);
//设置的下拉箭头的动画效果
RotateAnimationanimation2=newRotateAnimation(180,0,RotateAnimation.RELATIVE_TO_SELF,0.5f,RotateAnimation.RELATIVE_TO_SELF,0.5f);
animation2.setDuration(500);
animation2.setFillAfter(true);

/**
*四种状态动画的改变
*/
switch(state){
caseNONE:
arrow.clearAnimation();
topPadding(-headerHeight);
break;
casePULL:
arrow.setVisibility(View.VISIBLE);
header_pb.setVisibility(View.GONE);
tip.setText("下拉可以刷新！！");
arrow.clearAnimation();
arrow.setAnimation(animation2);
break;
caseRELESE:
arrow.setVisibility(View.VISIBLE);
header_pb.setVisibility(View.GONE);
tip.setText("松开可以刷新！！");
arrow.clearAnimation();
arrow.setAnimation(animation);
break;
caseREFLASHING:
topPadding(50);
arrow.setVisibility(View.GONE);
header_pb.setVisibility(View.VISIBLE);
tip.setText("正在刷新...");
arrow.clearAnimation();
break;
}

}

/**
*获取完整数据
*
*/
publicvoidreflashComplete(){
state=NONE;
isRemark=false;
reflashViewByState();
//设置刷新完成的时间
TextViewlasetupdate_time=(TextView)header.findViewById(R.id.tv_lastupdate_time);
SimpleDateFormatsimpleDateFormat=newSimpleDateFormat("yyyy年MM月dd日hh:mm:ss");
Datedate=newDate(System.currentTimeMillis());
Stringtime=simpleDateFormat.format(date);
lasetupdate_time.setText(time);

}

}

packagecom.example.administrator.listviewtest;

importandroid.os.Handler;
importandroid.support.v7.app.AppCompatActivity;
importandroid.os.Bundle;
importandroid.view.Menu;
importandroid.view.MenuItem;
importandroid.widget.ArrayAdapter;

importjava.util.ArrayList;
importjava.util.List;

importjava.util.logging.LogRecord;

publicclassMainActivityextendsAppCompatActivityimplementsLoadListView.ILoadListener,LoadListView.RLoadListener{
privateLoadListViewmListView;
privateList<String>datas;
privateArrayAdapter<String>arrayAdapter;

@Override
protectedvoidonCreate(BundlesavedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
setupViews();
initDatas();
}

privatevoidinitDatas(){
for(inti=0;i<16;i++){
datas.add("ListView的数据"+i+"");
}
}
privatevoidinitNewDatas(){
for(inti=0;i<3;i++){
datas.add("footer加载出的数据"+i+"");
}

}

privatevoidinitREflashDatas(){

datas.add(0,"下拉刷新加载的数据");

}

privatevoidsetupViews(){

mListView=(LoadListView)findViewById(R.id.lv_main);
//上拉加载接口
mListView.setInterface(this);
mListView.setReflashInterface(this);
datas=newArrayList<String>();
arrayAdapter=newArrayAdapter<String>(MainActivity.this,android.R.layout.simple_expandable_list_item_1,datas);
mListView.setAdapter(arrayAdapter);

}

//实现onLoad()方法。
@Override
publicvoidonLoad(){
//添加延时效果模拟数据加载
Handlerhandler=newHandler();
handler.postDelayed(newRunnable(){
@Override
publicvoidrun(){
initNewDatas();//得到新数据
arrayAdapter.notifyDataSetChanged();//刷新ListView;
mListView.loadCompleted();
}
},2000);
}
//实现的刷新方法
@Override
publicvoidonRefresh(){
Handlerhandler=newHandler();
handler.postDelayed(newRunnable(){
@Override
publicvoidrun(){
initREflashDatas();//得到新数据
arrayAdapter.notifyDataSetChanged();//刷新ListView;
mListView.reflashComplete();
}
},2000);

}

}