Android Recyclerview视图不能与setNestedScrollingEnabled一起使用,它也不会回收任何视图
我面临两个问题:Android Recyclerview视图不能与setNestedScrollingEnabled一起使用,它也不会回收任何视图,android,android-recyclerview,android-nestedscrollview,onscrolllistener,Android,Android Recyclerview,Android Nestedscrollview,Onscrolllistener,我面临两个问题: 滚动侦听器无法工作 RecyclerView在附加到NestedScrollView时从不回收任何视图。它在ScrollView中的作用类似于线性布局。它会占用大量内存并产生延迟 我在recycler视图的顶部附加了一个youtube播放器片段,因为我不能在recycler视图中放置一个片段。在我的代码中,您可以看到有一个框架布局 我的布局如下所示: <android.support.v4.widget.NestedScrollView xmlns:android
RecyclerView
在附加到NestedScrollView
时从不回收任何视图。它在ScrollView中的作用类似于线性布局。它会占用大量内存并产生延迟李>
我在recycler视图的顶部附加了一个youtube播放器片段,因为我不能在recycler视图中放置一个片段。在我的代码中,您可以看到有一个框架布局
我的布局如下所示:
<android.support.v4.widget.NestedScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/nestedScroll"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#ffffff"
android:orientation="vertical">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#ffffff"
android:orientation="vertical">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="240dp"
android:layout_alignParentTop="true"/>
</LinearLayout>
<android.support.v7.widget.RecyclerView
android:id="@+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/youtube_layout"
android:visibility="visible"/>
</LinearLayout>
</android.support.v4.widget.NestedScrollView>
但是在我开始滚动之前,recylerview会一次绑定所有视图,所以这种方法也不起作用。我就是这样做到的,我尝试将代码剥离到最低限度
public class DataAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private static final int VIEW_TYPE_LOADING = 0;
private static final int VIEW_TYPE_ITEM = 1;
public boolean isLoading;
private int visibleThreshold = 5;
private int lastVisibleItem, totalItemCount;
public ArrayList<Data> datas;
private OnLoadMoreListener mOnLoadMoreListener;
public DataAdapter(RecyclerView mRecyclerView, ArrayList<Data> datas) {
this.datas = datas;
final LinearLayoutManager linearLayoutManager = (LinearLayoutManager) mRecyclerView.getLayoutManager();
mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
totalItemCount = linearLayoutManager.getItemCount();
lastVisibleItem = linearLayoutManager.findLastVisibleItemPosition();
if (!isLoading && totalItemCount <= (lastVisibleItem + visibleThreshold)) {
if (mOnLoadMoreListener != null) {
DataAdapter.this.datas.remove(null);
mOnLoadMoreListener.onLoadMore();
}
}
}
});
}
public static class DataObjectHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
//your views
public DataObjectHolder(View itemView) {
super(itemView);
//initialize your views
}
@Override
public void onClick(View v) {
if (onItemClickListener != null) onItemClickListener.onItemClick(getAdapterPosition(), v);
}
}
public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
this.onItemClickListener = onItemClickListener;
}
@Override
public int getItemViewType(int position) {
return datas.get(position) == null ? VIEW_TYPE_LOADING : VIEW_TYPE_ITEM;
}
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == VIEW_TYPE_ITEM) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_item_data, parent, false);
DataObjectHolder dataObjectHolder = new DataObjectHolder(view);
return dataObjectHolder;
} else if (viewType == VIEW_TYPE_LOADING) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.layout_loading_item, parent, false);
return new LoadingViewHolder(view);
}
return null;
}
@Override
public void onBindViewHolder(final RecyclerView.ViewHolder hldr, final int position) {
if (hldr instanceof DataObjectHolder) {
final Data data = datas.get(position);
final DataObjectHolder holder = (DataObjectHolder) hldr;
//bind your views
} else if (hldr instanceof LoadingViewHolder) {
LoadingViewHolder loadingViewHolder = (LoadingViewHolder) hldr;
if (isLoading) {
loadingViewHolder.progressBar.setVisibility(View.VISIBLE);
loadingViewHolder.progressBar.setIndeterminate(true);
loadingViewHolder.tv_load_more.setVisibility(View.GONE);
loadingViewHolder.tv_load_more.setOnClickListener(null);
} else {
loadingViewHolder.progressBar.setVisibility(View.GONE);
loadingViewHolder.tv_load_more.setVisibility(View.VISIBLE);
loadingViewHolder.tv_load_more.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (mOnLoadMoreListener != null) {
datas.remove(null);
mOnLoadMoreListener.onLoadMore();
}
}
});
}
}
}
@Override
public int getItemCount() {
return datas.size();
}
public void setOnLoadMoreListener(OnLoadMoreListener mOnLoadMoreListener) {
this.mOnLoadMoreListener = mOnLoadMoreListener;
}
}
公共类DataAdapter扩展了RecyclerView.Adapter{
私有静态最终整型视图\类型\加载=0;
私有静态最终整数视图\类型\项=1;
公共布尔孤岛加载;
私有int visibleThreshold=5;
private int lastVisibleItem,totalItemCount;
公共阵列列表数据;
私有OnLoadMoreListener mOnLoadMoreListener;
公共数据适配器(RecyclerView mRecyclerView、ArrayList数据){
this.datas=datas;
最终LinearLayoutManager LinearLayoutManager=(LinearLayoutManager)mRecyclerView.getLayoutManager();
mrecycleView.addOnScrollListener(新的RecycleView.OnScrollListener(){
@凌驾
已填空的公共空间(RecyclerView RecyclerView、int dx、int dy){
super.onScrolled(recyclerView、dx、dy);
totalItemCount=linearLayoutManager.getItemCount();
lastVisibleItem=linearLayoutManager.findLastVisibleItemPosition();
如果(!isLoading&&totalItemCount)
当它连接到嵌套的滚动视图时,回收器视图从不回收任何视图,它在滚动视图内的线性布局上起到设置的作用。它创建了巨大的内存并滞后于屏幕
没错。你不能在另一个滚动视图中放置RecyclerView
这将不起作用,因为包装视图需要知道RecyclerView的总高度,而RecyclerView只能通过测量和布局其所有项目来知道其总高度
如何解决这个问题?
不要将RecyclerView放在另一个滚动视图中。
如果您需要页眉或页脚,则必须将其添加到RecyclerView中,并让RecyclerView负责显示该页眉或页脚。取消滚动视图,将页眉移动到RecyclerView中
从技术上讲,也可以在RecyclerView中加载片段,但我必须承认,让它正常工作有点棘手
还有很多库可以促进这一过程,我个人最喜欢的库是AirBnb制作的,但也有,还有很多其他库。我处理过这种情况。有一个recyclerview。recyclerview有viewpager。viewpager有片段,片段中有一个recyclerview
你需要破解触摸,使其完美滚动
private boolean interceptTouch = true;
private static final int MIN_DISTANCE = 200;
private float downX = 0, downY = 0, moveX = 0, moveY = 0, upX = 0, upY;
public TouchInterceptRecyclerView(Context context) {
super(context);
}
public TouchInterceptRecyclerView(Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
}
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
if (getRvTop() == 0) {
onTouchEvent(ev);
}
return interceptTouch;
}
@Override
public boolean onTouchEvent(MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
downX = event.getX();
downY = event.getY();
break;
case MotionEvent.ACTION_MOVE:
moveX = event.getX();
moveY = event.getY();
break;
case MotionEvent.ACTION_UP:
upX = event.getX();
upY = event.getY();
break;
}
float deltaX = upX - downX;
if (getViewTop() == 0 && moveY > downY && Math.abs(moveY - downY) > MIN_DISTANCE) { // moving down
interceptTouch = true;
}else if (Math.abs(deltaX) > MIN_DISTANCE) {
if (upX > downX) { // Left to Right swipe action
interceptTouch = false;
}else { // Right to left swipe action
interceptTouch = false;
}
} else { // screen tap
interceptTouch = false;
}
return super.onTouchEvent(event);
}
@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
return super.dispatchTouchEvent(ev);
}
@Override
protected void onScrollChanged(int l, int t, int oldl, int oldt) {
super.onScrollChanged(l, t, oldl, oldt);
}
@Override
public void onScrolled(int dx, int dy) {
if (getViewTop() <= 0) {
interceptTouch = false; // dispatch the touch to child when reached top
} else {
interceptTouch = true; // do not dispatch the touch event
}
super.onScrolled(dx, dy);
}
public int getViewTop() {
int top = 0;
View v = this.getChildAt(1);
if (v == null) {
v = this.getChildAt(0);
}
if (v != null && v instanceof LinearLayout) {
top = v.getTop();
}
return top;
}
public int getRvTop() {
int top = -1;
View v = this.getChildAt(1);
if (v == null) {
v = this.getChildAt(0);
}
if (v != null && v instanceof LinearLayout) {
ViewPager vp = (ViewPager) v.findViewById(R.id.single_tribe_pager);
if (vp != null) {
int currentPos = vp.getCurrentItem();
RecyclerView rv = (RecyclerView) vp.findViewWithTag("recyclerview" + currentPos);
if (rv != null) {
View v1 = rv.getChildAt(0);
if (v1 != null && v1 instanceof CardView) {
top = v1.getTop() - ResourceUtils.getDimensionPixelOffset(R.dimen.padding_20); // deducting 20 as we have give top margin as 20 to the top layout
}
}
}
}
return top;
}
private boolean-touch=true;
专用静态最终整数最小距离=200;
私有浮动downX=0,downY=0,moveX=0,moveY=0,upX=0,upY;
公共TouchInterceptRecyclerView(上下文){
超级(上下文);
}
公共TouchInterceptRecyclerView(上下文上下文,@Nullable AttributeSet attrs){
超级(上下文,attrs);
}
@凌驾
公共布尔值onInterceptTouchEvent(MotionEvent ev){
if(getRvTop()==0){
火山口(ev);
}
回击;
}
@凌驾
公共布尔onTouchEvent(运动事件){
开关(event.getAction()){
case MotionEvent.ACTION\u DOWN:
downX=event.getX();
downY=event.getY();
打破
case MotionEvent.ACTION\u移动:
moveX=event.getX();
moveY=event.getY();
打破
case MotionEvent.ACTION\u UP:
upX=event.getX();
upY=event.getY();
打破
}
浮动deltaX=upX-downX;
如果(getViewTop()==0&&moveY>downY&&Math.abs(moveY-downY)>minu距离){//向下移动
触摸=真;
}else if(数学绝对值(deltaX)>最小距离){
如果(upX>downX){//从左向右滑动操作
触摸=假;
}else{//从右向左滑动操作
触摸=假;
}
}else{//屏幕点击
触摸=假;
}
返回super.onTouchEvent(事件);
}
@凌驾
公共布尔dispatchTouchEvent(MotionEvent ev){
返回超级dispatchTouchEvent(ev);
}
@凌驾
CrollChanged上的受保护无效(int l、int t、int oldl、int oldt){
super.onScrollChanged(l,t,oldl,oldt);
}
@凌驾
已填空的公共空间(整数dx,整数dy){
if(getViewTop()我正在使用recyclerview顶部的fragment。我不能这样写哦,对不起,我是在回答另一个问题。如果您确定您发布的答案有误,请随意删除您的答案。您知道吗,yh我没有发布错误问题的答案。我解决了在滚动到底部时将更多项目加载到recycler视图的问题。正如其他人所指出的,你不能在回收器视图中使用片段。总有更好的方法来实现你的目标。我已经加载了片段,但回收器视图不允许片段状态。它会随机崩溃。
public class DataAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private static final int VIEW_TYPE_LOADING = 0;
private static final int VIEW_TYPE_ITEM = 1;
public boolean isLoading;
private int visibleThreshold = 5;
private int lastVisibleItem, totalItemCount;
public ArrayList<Data> datas;
private OnLoadMoreListener mOnLoadMoreListener;
public DataAdapter(RecyclerView mRecyclerView, ArrayList<Data> datas) {
this.datas = datas;
final LinearLayoutManager linearLayoutManager = (LinearLayoutManager) mRecyclerView.getLayoutManager();
mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
totalItemCount = linearLayoutManager.getItemCount();
lastVisibleItem = linearLayoutManager.findLastVisibleItemPosition();
if (!isLoading && totalItemCount <= (lastVisibleItem + visibleThreshold)) {
if (mOnLoadMoreListener != null) {
DataAdapter.this.datas.remove(null);
mOnLoadMoreListener.onLoadMore();
}
}
}
});
}
public static class DataObjectHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
//your views
public DataObjectHolder(View itemView) {
super(itemView);
//initialize your views
}
@Override
public void onClick(View v) {
if (onItemClickListener != null) onItemClickListener.onItemClick(getAdapterPosition(), v);
}
}
public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
this.onItemClickListener = onItemClickListener;
}
@Override
public int getItemViewType(int position) {
return datas.get(position) == null ? VIEW_TYPE_LOADING : VIEW_TYPE_ITEM;
}
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == VIEW_TYPE_ITEM) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_item_data, parent, false);
DataObjectHolder dataObjectHolder = new DataObjectHolder(view);
return dataObjectHolder;
} else if (viewType == VIEW_TYPE_LOADING) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.layout_loading_item, parent, false);
return new LoadingViewHolder(view);
}
return null;
}
@Override
public void onBindViewHolder(final RecyclerView.ViewHolder hldr, final int position) {
if (hldr instanceof DataObjectHolder) {
final Data data = datas.get(position);
final DataObjectHolder holder = (DataObjectHolder) hldr;
//bind your views
} else if (hldr instanceof LoadingViewHolder) {
LoadingViewHolder loadingViewHolder = (LoadingViewHolder) hldr;
if (isLoading) {
loadingViewHolder.progressBar.setVisibility(View.VISIBLE);
loadingViewHolder.progressBar.setIndeterminate(true);
loadingViewHolder.tv_load_more.setVisibility(View.GONE);
loadingViewHolder.tv_load_more.setOnClickListener(null);
} else {
loadingViewHolder.progressBar.setVisibility(View.GONE);
loadingViewHolder.tv_load_more.setVisibility(View.VISIBLE);
loadingViewHolder.tv_load_more.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (mOnLoadMoreListener != null) {
datas.remove(null);
mOnLoadMoreListener.onLoadMore();
}
}
});
}
}
}
@Override
public int getItemCount() {
return datas.size();
}
public void setOnLoadMoreListener(OnLoadMoreListener mOnLoadMoreListener) {
this.mOnLoadMoreListener = mOnLoadMoreListener;
}
}
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="60dp">
<ProgressBar
android:id="@+id/progressBar1"
android:layout_width="20dp"
android:layout_height="20dp"
android:layout_centerInParent="true"
android:layout_gravity="center"
android:indeterminate="true"/>
<TextView
android:id="@+id/tv_load_more"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_centerInParent="true"
android:gravity="center"
android:text="Tap to load more"
android:textSize="14sp"/>
</RelativeLayout>
private boolean interceptTouch = true;
private static final int MIN_DISTANCE = 200;
private float downX = 0, downY = 0, moveX = 0, moveY = 0, upX = 0, upY;
public TouchInterceptRecyclerView(Context context) {
super(context);
}
public TouchInterceptRecyclerView(Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
}
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
if (getRvTop() == 0) {
onTouchEvent(ev);
}
return interceptTouch;
}
@Override
public boolean onTouchEvent(MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
downX = event.getX();
downY = event.getY();
break;
case MotionEvent.ACTION_MOVE:
moveX = event.getX();
moveY = event.getY();
break;
case MotionEvent.ACTION_UP:
upX = event.getX();
upY = event.getY();
break;
}
float deltaX = upX - downX;
if (getViewTop() == 0 && moveY > downY && Math.abs(moveY - downY) > MIN_DISTANCE) { // moving down
interceptTouch = true;
}else if (Math.abs(deltaX) > MIN_DISTANCE) {
if (upX > downX) { // Left to Right swipe action
interceptTouch = false;
}else { // Right to left swipe action
interceptTouch = false;
}
} else { // screen tap
interceptTouch = false;
}
return super.onTouchEvent(event);
}
@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
return super.dispatchTouchEvent(ev);
}
@Override
protected void onScrollChanged(int l, int t, int oldl, int oldt) {
super.onScrollChanged(l, t, oldl, oldt);
}
@Override
public void onScrolled(int dx, int dy) {
if (getViewTop() <= 0) {
interceptTouch = false; // dispatch the touch to child when reached top
} else {
interceptTouch = true; // do not dispatch the touch event
}
super.onScrolled(dx, dy);
}
public int getViewTop() {
int top = 0;
View v = this.getChildAt(1);
if (v == null) {
v = this.getChildAt(0);
}
if (v != null && v instanceof LinearLayout) {
top = v.getTop();
}
return top;
}
public int getRvTop() {
int top = -1;
View v = this.getChildAt(1);
if (v == null) {
v = this.getChildAt(0);
}
if (v != null && v instanceof LinearLayout) {
ViewPager vp = (ViewPager) v.findViewById(R.id.single_tribe_pager);
if (vp != null) {
int currentPos = vp.getCurrentItem();
RecyclerView rv = (RecyclerView) vp.findViewWithTag("recyclerview" + currentPos);
if (rv != null) {
View v1 = rv.getChildAt(0);
if (v1 != null && v1 instanceof CardView) {
top = v1.getTop() - ResourceUtils.getDimensionPixelOffset(R.dimen.padding_20); // deducting 20 as we have give top margin as 20 to the top layout
}
}
}
}
return top;
}