Android实现RecyclerView下拉刷新效果

2024-02-04 17:50:04 66

本文为大家分享了Android实现RecyclerView下拉刷新效果的具体代码，供大家参考，具体内容如下

思路

RealPullRefreshView继承了一个LinearLayout
里面放置了一个刷新头布局，将其margin_top设置为负的刷新头的高度的
再添加一个RecyclerView
触摸事件分发机制，当在特定条件下让RealPullRefreshView拦截触摸事件，否则的话，不拦截，让RecyclerView自己去处理触摸事件
在手指下拉时，定义好不同的状态STATE,在不同状态下，处理不同的显示，这里讲不同状态下的刷新头如何显示，抽象为一个接口，用户可以实现这个接口，自定义刷新头的布局和动画
加载更多的功能是利用RecyclerView的多type布局实现的
难点在于触摸事件的拦截，和认真处理各种滑动的问题

使用

xml

这是headerview

代码

mRealPullRefreshView.setLayoutManager(mLayoutManager);
mRealPullRefreshView.setAdapter(mMyAdapte);
//用户可以自定义自己的刷新头布局和动画
//mRealPullRefreshView.setOnPullShowViewListener(newGifOnPullShowViewListerner(mRealPullRefreshView));

mRealPullRefreshView.setOnPullListener(newRealPullRefreshView.OnPullListener(){
@Override
publicvoidonRefresh(){

mHandler.postDelayed(newRunnable(){
@Override
publicvoidrun(){
mBodies.add(0,newBody("新数据"+i++,100));
mRealPullRefreshView.refreshFinish();
}
},3000);

}

@Override
publicvoidonLoadMore(){

finalListmore=newArrayList();
mHandler.postDelayed(newRunnable(){
@Override
publicvoidrun(){
for(inti=0;i<3;i++){
more.add(newBody("more+++"+i,100));

}


mBodies.addAll(more);
mRealPullRefreshView.loadMreFinish();
}
},1500);

}
});

自定义刷新头布局和动画

packagecom.example.apple.quickdemo.realview.show;

importandroid.animation.ObjectAnimator;
importandroid.animation.ValueAnimator;
importandroid.util.Log;
importandroid.view.View;
importandroid.widget.ImageView;
importandroid.widget.TextView;

importcom.example.apple.quickdemo.R;
importcom.example.apple.quickdemo.realview.view.RealPullRefreshView;

/**
*Createdbyappleon2017/7/9.
*/

publicclassImplOnPullShowViewListenerimplementsRealPullRefreshView.OnPullShowViewListener{

privateTextViewmTv;
privateImageViewmIv;
privateObjectAnimatormAni;
ViewmHeaderView;


publicImplOnPullShowViewListener(RealPullRefreshViewrealPullRefreshView){
mHeaderView=realPullRefreshView.getRefreshHeaderView();
mTv=(TextView)mHeaderView.findViewById(R.id.tv);
mIv=(ImageView)mHeaderView.findViewById(R.id.iv);
mAni=ObjectAnimator.ofFloat(mIv,"rotation",-15,15).setDuration(300);
mAni.setRepeatCount(ValueAnimator.INFINITE);
mAni.setRepeatMode(ValueAnimator.REVERSE);
}

@Override
publicvoidonPullDownRefreshState(intscrollY,intheadviewHeight,intdeltaY){
mTv.setText("下拉刷新");
floatf=-((float)scrollY/(float)headviewHeight);
Log.e("tag",f+"");
Log.e("tag",-scrollY+"scrollY");


mIv.setScaleX(f);
mIv.setScaleY(f);
}

@Override
publicvoidonReleaseRefreshState(intscrollY,intdeltaY){
mTv.setText("松手刷新");

}

@Override
publicvoidonRefreshingState(){
mTv.setText("正在刷新");
mIv.setScaleX(1.0f);
mIv.setScaleY(1.0f);
mAni.start();

}

@Override
publicvoidonDefaultState(){
if(mAni.isRunning()){
mAni.end();
mIv.setRotation(0);
}
}

}

源码

packagecom.example.apple.quickdemo.realview.view;

importandroid.content.Context;
importandroid.content.res.TypedArray;
importandroid.support.annotation.Nullable;
importandroid.support.v7.widget.GridLayoutManager;
importandroid.support.v7.widget.LinearLayoutManager;
importandroid.support.v7.widget.RecyclerView;
importandroid.support.v7.widget.StaggeredGridLayoutManager;
importandroid.util.AttributeSet;
importandroid.util.Log;
importandroid.view.LayoutInflater;
importandroid.view.MotionEvent;
importandroid.view.VelocityTracker;
importandroid.view.View;
importandroid.view.ViewGroup;
importandroid.widget.LinearLayout;
importandroid.widget.Scroller;
importandroid.widget.Toast;

importcom.example.apple.quickdemo.R;
importcom.example.apple.quickdemo.realview.show.ImplOnPullShowViewListener;

importstaticandroid.content.ContentValues.TAG;

/**
*Createdbyappleon2017/7/7.
*下拉刷新
*/

publicclassRealPullRefreshViewextendsLinearLayout{


privateintmTouchSlop;
//分别记录上次滑动的坐标
privateintmLastX=0;
privateintmLastY=0;

//分别记录上次滑动的坐标(onInterceptTouchEnvent)
privateintmLastXIntercept=0;
privateintmLastYIntercept=0;

privateScrollermScroller;
privateVelocityTrackermVelocityTracker;


privateRecyclerView.AdaptermAdapter;

publicRecyclerViewgetRecyclerView(){
returnmRecyclerView;
}

privateRecyclerViewmRecyclerView;


privateintDEFAULT=0;
privatefinalintPULL_DOWN_REFRESH=1;
privatefinalintRELEASE_REFRESH=2;
privatefinalintREFRESHING=3;
privatefinalintLOAD_MORE=4;
privateintSTATE=DEFAULT;


privateintrfreshHeaderWidth;
privateintrefreshHeadviewHeight;


privateOnPullListenermOnPullListener;
privateViewmRefreshHeaderView;

privateRecyclerView.LayoutManagermLayoutManager;


intrefreshHeadviewId;

publicvoidsetLayoutManager(RecyclerView.LayoutManagermanager){
this.mLayoutManager=manager;
mRecyclerView.setLayoutManager(mLayoutManager);

}

publicvoidsetAdapter(RecyclerView.Adapteradapter){
this.mAdapter=adapter;
mRecyclerView.setAdapter(mAdapter);

}

publicViewgetRefreshHeaderView(){
returnmRefreshHeaderView;
}

publicvoidsetOnPullShowViewListener(OnPullShowViewListeneronPullShowViewListener){
mOnPullShowViewListener=onPullShowViewListener;
}

privateOnPullShowViewListenermOnPullShowViewListener;

publicvoidsetOnPullListener(OnPullListeneronPullListener){
mOnPullListener=onPullListener;
}

publicRealPullRefreshView(Contextcontext){
super(context);

initView(context);

}

publicRealPullRefreshView(Contextcontext,@NullableAttributeSetattrs){
super(context,attrs);

initAttrs(context,attrs);
//★★★★★一个坑initAttrs方法里的typedArray去获取属性时，第一次获取的属性全是0，他会马上重走一次构造方法，再次获取一次，才能获得正确的值
//如果第一次获取的值为0，则不去initView
if(refreshHeadviewId!=0){
initView(context);
}


}


publicRealPullRefreshView(Contextcontext,@NullableAttributeSetattrs,intdefStyleAttr){
super(context,attrs,defStyleAttr);

initAttrs(context,attrs);
if(refreshHeadviewId!=0){
initView(context);
}
}

privatevoidinitAttrs(Contextcontext,AttributeSetattrs){

TypedArraytypedArray=context.obtainStyledAttributes(attrs,R.styleable.RealPullRefreshView);

try{

refreshHeadviewId=typedArray.getResourceId(R.styleable.RealPullRefreshView_refresh_header_view,0);


}finally{
typedArray.recycle();

}


}


privatevoidinitView(Contextcontext){

mScroller=newScroller(getContext());
mVelocityTracker=VelocityTracker.obtain();


//添加headerview

//★★★★★注意不要用这个方法inflate布局，会导致layout的所有属性失效，height、width、margin
//原因见http://blog.csdn.net/zhaokaiqiang1992/article/details/36006467
//★★★★★mRefreshHeaderView=mInflater.inflate(R.layout.headerview,null);

mRefreshHeaderView=LayoutInflater.from(context).inflate(refreshHeadviewId,this,false);
addView(mRefreshHeaderView);
//}

//以下代码主要是为了设置头布局的marginTop值为-headerviewHeight
//注意必须等到一小会才会得到正确的头布局宽高
postDelayed(newRunnable(){
@Override
publicvoidrun(){
Log.e("q11",refreshHeadviewHeight+"qqqqqqqqqq"+mRefreshHeaderView.getHeight());
rfreshHeaderWidth=mRefreshHeaderView.getWidth();
refreshHeadviewHeight=mRefreshHeaderView.getHeight();

MarginLayoutParamslp=newLinearLayout.LayoutParams(rfreshHeaderWidth,refreshHeadviewHeight);
lp.setMargins(0,-refreshHeadviewHeight,0,0);
mRefreshHeaderView.setLayoutParams(lp);

}
},100);


//添加RecyclerView
mRecyclerView=newRecyclerView(context);
addView(mRecyclerView,LayoutParams.MATCH_PARENT,ViewGroup.LayoutParams.MATCH_PARENT);


//这里我提供了一个默认的显示效果，如果用户不使用mRealPullRefreshView.setOnPullShowViewListener的话，会默认使用这个
//用户可以实现OnPullShowViewListener接口，去实现自己想要的显示效果
mOnPullShowViewListener=newImplOnPullShowViewListener(this);


setLoadMore();


}

privatevoidsetLoadMore(){
//当目前的可见条目是所有数据的最后一个时，开始加载新的数据

mRecyclerView.addOnScrollListener(newRecyclerView.OnScrollListener(){

@Override
publicvoidonScrolled(RecyclerViewrecyclerView,intdx,intdy){
super.onScrolled(recyclerView,dx,dy);

intlastCompletelyVisibleItemPosition=-1;
if(mLayoutManagerinstanceofLinearLayoutManager){
LinearLayoutManagermanager=(LinearLayoutManager)mLayoutManager;
lastCompletelyVisibleItemPosition=manager.findLastVisibleItemPosition();

}elseif(mLayoutManagerinstanceofGridLayoutManager){
GridLayoutManagermanager=(GridLayoutManager)mLayoutManager;
lastCompletelyVisibleItemPosition=manager.findLastVisibleItemPosition();

}elseif(mLayoutManagerinstanceofStaggeredGridLayoutManager){
StaggeredGridLayoutManagermanager=(StaggeredGridLayoutManager)mLayoutManager;
lastCompletelyVisibleItemPosition=manager.findLastVisibleItemPositions(newint[manager.getSpanCount()])[0];
}
if(lastCompletelyVisibleItemPosition+1==mAdapter.getItemCount()){
if(mOnPullListener!=null&&STATE==DEFAULT){
STATE=LOAD_MORE;
mOnPullListener.onLoadMore();
}
}


}
});
}


@Override
publicbooleanonInterceptTouchEvent(MotionEventevent){
booleanintercepted=false;
intx=(int)event.getX();
inty=(int)event.getY();

switch(event.getAction()){
caseMotionEvent.ACTION_DOWN:{
intercepted=false;
/*if(STATE!=DEFAULT||STATE!=REFRESHING){
if(!mScroller.isFinished()){
mScroller.abortAnimation();
}}*/
break;
}
caseMotionEvent.ACTION_MOVE:{
intdeltaX=x-mLastXIntercept;
intdeltaY=y-mLastYIntercept;

intfirstCompletelyVisibleItemPosition=-1;
if(mLayoutManagerinstanceofLinearLayoutManager){
LinearLayoutManagermanager=(LinearLayoutManager)mLayoutManager;
firstCompletelyVisibleItemPosition=manager.findFirstCompletelyVisibleItemPosition();

}elseif(mLayoutManagerinstanceofGridLayoutManager){
GridLayoutManagermanager=(GridLayoutManager)mLayoutManager;
firstCompletelyVisibleItemPosition=manager.findFirstCompletelyVisibleItemPosition();

}elseif(mLayoutManagerinstanceofStaggeredGridLayoutManager){
StaggeredGridLayoutManagermanager=(StaggeredGridLayoutManager)mLayoutManager;
firstCompletelyVisibleItemPosition=manager.findFirstCompletelyVisibleItemPositions(newint[manager.getSpanCount()])[0];
}


//******************这里说明什么规则下，拦截，其余代码不要动了，其余代码指的是处理滑动冲突的代码***************


if(firstCompletelyVisibleItemPosition==0&&deltaY>0&&Math.abs(deltaY)>Math.abs(deltaX)){//拉倒最顶部，继续往下拉，将拉出头布局，要父布局拦截
intercepted=true;
}elseif(getScrollY()<0){//表示头布局已经向下拉出来，头布局已经显示了，要父布局拦截
intercepted=true;

}elseif(deltaY<0){
intercepted=false;//不要父布局拦截了

}else{
intercepted=false;//不要父布局拦截了
}
//******************什么规则下，拦截***************

break;
}
caseMotionEvent.ACTION_UP:{
intercepted=false;
break;
}
default:
break;
}

Log.d(TAG,"intercepted="+intercepted);
mLastX=x;
mLastY=y;
mLastXIntercept=x;
mLastYIntercept=y;

returnintercepted;
}


/**
*下面不同布局，不同的滑动需求
*
*@paramevent
*@return
*/
@Override
publicbooleanonTouchEvent(MotionEventevent){
mVelocityTracker.addMovement(event);
intx=(int)event.getX();
inty=(int)event.getY();
switch(event.getAction()){
caseMotionEvent.ACTION_DOWN:{
if(!mScroller.isFinished()){
mScroller.abortAnimation();
}
break;
}
caseMotionEvent.ACTION_MOVE:{
intdeltaX=x-mLastX;
intdeltaY=y-mLastY;
if(getScrollY()>0){
//防止在正在刷新状态下，上拉出空白
}elseif(getScrollY()<=0&&getScrollY()>-refreshHeadviewHeight*5){
//最多下拉到头布局高度5倍的距离
scrollBy(0,-deltaY/2);
}

if(getScrollY()>-refreshHeadviewHeight&&STATE!=REFRESHING){//头布局显示不全时，为下拉刷新PULL_DOWN_REFRESH状态
STATE=PULL_DOWN_REFRESH;

if(mOnPullShowViewListener!=null){
mOnPullShowViewListener.onPullDownRefreshState(getScrollY(),refreshHeadviewHeight,deltaY);
}

}
if(getScrollY()<-refreshHeadviewHeight&&STATE!=REFRESHING){//头布局完全显示时，为释放刷新RELEASE_REFRESH状态
STATE=RELEASE_REFRESH;
if(mOnPullShowViewListener!=null){
mOnPullShowViewListener.onReleaseRefreshState(getScrollY(),deltaY);
}

}

break;
}
caseMotionEvent.ACTION_UP:{
finalintscrollY=getScrollY();
//松手时，根据所处的状态，让布局滑动到不同的地方，做不同的操作
switch(STATE){

casePULL_DOWN_REFRESH:
STATE=DEFAULT;
//头布局没有完全显示，完全隐藏头布局
smoothScrollBy(0,-scrollY);
break;
caseRELEASE_REFRESH:
STATE=REFRESHING;
smoothScrollBy(0,-refreshHeadviewHeight-scrollY);


if(mOnPullShowViewListener!=null){
mOnPullShowViewListener.onRefreshingState();
}


if(mOnPullListener!=null){
mOnPullListener.onRefresh();
}
break;
caseREFRESHING:
if(getScrollY()<-refreshHeadviewHeight){
smoothScrollBy(0,-refreshHeadviewHeight-scrollY);
}else{
smoothScrollBy(0,-scrollY);
}
break;
}

mVelocityTracker.clear();
break;
}
default:
break;
}

mLastX=x;
mLastY=y;
returntrue;
}

/**
*当用户使用完下拉刷新回调时，需要调用此方法，将头不去隐藏，将STATE恢复
*/
publicvoidrefreshFinish(){
smoothScrollBy(0,0-getScrollY());
getRecyclerView().getAdapter().notifyDataSetChanged();
STATE=DEFAULT;
if(mOnPullShowViewListener!=null){
mOnPullShowViewListener.onDefaultState();
}

Toast.makeText(getContext(),"刷新成功!",Toast.LENGTH_SHORT).show();
}

/**
*当用户使用完加载更多后回调时，需要调用此方法，将STATE恢复
*/
publicvoidloadMreFinish(){
getRecyclerView().getAdapter().notifyDataSetChanged();
STATE=DEFAULT;

Toast.makeText(getContext(),"加载成功了!",Toast.LENGTH_SHORT).show();
}

/**
*在500毫秒内平滑地滚动多少像素点
*
*@paramdx
*@paramdy
*/
privatevoidsmoothScrollBy(intdx,intdy){
mScroller.startScroll(0,getScrollY(),0,dy,500);
invalidate();
}

@Override
publicvoidcomputeScroll(){
if(mScroller.computeScrollOffset()){
scrollTo(mScroller.getCurrX(),mScroller.getCurrY());
postInvalidate();
}
}

/**
*释放资源
*/
@Override
protectedvoidonDetachedFromWindow(){
mVelocityTracker.recycle();
super.onDetachedFromWindow();
}


//***************


//*****************

/**
*回调接口
*/
publicinterfaceOnPullListener{
/**
*当下拉刷新正在刷新时，这时候可以去请求数据，记得最后调用refreshFinish()复位
*/
voidonRefresh();

/**
*当加载更多时
*/
voidonLoadMore();
}


/**
*回调接口，可以通过下面的回调，自定义各种状态下的显示效果
*可以根据下拉距离scrollY设计动画效果
*/
publicinterfaceOnPullShowViewListener{

/**
*当处于下拉刷新时，头布局显示效果
*
*@paramscrollY下拉的距离
*@paramheadviewHeight头布局高度
*@paramdeltaYmoveY-lastMoveY,正值为向下拉
*/
voidonPullDownRefreshState(intscrollY,intheadviewHeight,intdeltaY);

/**
*当处于松手刷新时，头布局显示效果
*
*@paramscrollY下拉的距离
*@paramdeltaYmoveY-lastMoveY,正值为向下拉
*/
voidonReleaseRefreshState(intscrollY,intdeltaY);

/**
*正在刷新时，页面的显示效果
*/
voidonRefreshingState();

/**
*默认状态时，页面显示效果，主要是为了复位各种状态
*/
voidonDefaultState();


}
}

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持毛票票。

Android实现RecyclerView下拉刷新效果

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