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스크롤하는 동안 RecyclerView가 최하위 위치에 도달 할 때 감지
RecyclerView에 대한 코드가 있습니다.
recyclerView = (RecyclerView)rootview.findViewById(R.id.fabric_recyclerView);
recyclerView.setLayoutManager(layoutManager);
recyclerView.addItemDecoration(new RV_Item_Spacing(5));
FabricAdapter fabricAdapter=new FabricAdapter(ViewAdsCollection.getFabricAdsDetailsAsArray());
recyclerView.setAdapter(fabricAdapter);
스크롤하는 동안 RecyclerView가 최하위 위치에 도달하는시기를 알아야합니다. 가능합니까? 그렇다면 어떻게?
이를 수행하는 간단한 방법도 있습니다.
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
if (!recyclerView.canScrollVertically(1)) {
Toast.makeText(YourActivity.this, "Last", Toast.LENGTH_LONG).show();
}
}
});
방향 정수 : 업은 -1, 다운은 1, 0은 항상 거짓을 반환합니다.
recyclerview에 addOnScrollListener ()를 구현하기 만하면됩니다. 그런 다음 스크롤 리스너 내부에서 아래 코드를 구현합니다.
RecyclerView.OnScrollListener mScrollListener = new RecyclerView.OnScrollListener() {
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
if (mIsLoading)
return;
int visibleItemCount = mLayoutManager.getChildCount();
int totalItemCount = mLayoutManager.getItemCount();
int pastVisibleItems = mLayoutManager.findFirstVisibleItemPosition();
if (pastVisibleItems + visibleItemCount >= totalItemCount) {
//End of list
}
}
};
답변은 Kotlin에 있으며 Java에서 작동합니다. 복사하여 붙여 넣으면 IntelliJ가 자동으로 변환해야합니다.
recyclerView.addOnScrollListener(object : RecyclerView.OnScrollListener(){
override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
// 3 lines below are not needed.
Log.d("TAG","Last visible item is: ${gridLayoutManager.findLastVisibleItemPosition()}")
Log.d("TAG","Item count is: ${gridLayoutManager.itemCount}")
Log.d("TAG","end? : ${gridLayoutManager.findLastVisibleItemPosition() == gridLayoutManager.itemCount-1}")
if(gridLayoutManager.findLastVisibleItemPosition() == gridLayoutManager.itemCount-1){
// We have reached the end of the recycler view.
}
super.onScrolled(recyclerView, dx, dy)
}
})
LinearLayoutManager위에서 사용 된 것과 동일한 방법이 있기 때문에 이것은 또한 작동합니다 . 즉 findLastVisibleItemPosition(), getItemCount()( itemCountKotlin에서).
반복 호출을 방지하려면이 코드를 사용하십시오.
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
if (!recyclerView.canScrollVertically(1) && newState==RecyclerView.SCROLL_STATE_IDLE) {
Log.d("-----","end");
}
}
});
내 구현이 있으며 StaggeredGridLayout.
사용법 :
private EndlessScrollListener scrollListener =
new EndlessScrollListener(new EndlessScrollListener.RefreshList() {
@Override public void onRefresh(int pageNumber) {
//end of the list
}
});
rvMain.addOnScrollListener(scrollListener);
리스너 구현 :
class EndlessScrollListener extends RecyclerView.OnScrollListener {
private boolean isLoading;
private boolean hasMorePages;
private int pageNumber = 0;
private RefreshList refreshList;
private boolean isRefreshing;
private int pastVisibleItems;
EndlessScrollListener(RefreshList refreshList) {
this.isLoading = false;
this.hasMorePages = true;
this.refreshList = refreshList;
}
@Override public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
StaggeredGridLayoutManager manager =
(StaggeredGridLayoutManager) recyclerView.getLayoutManager();
int visibleItemCount = manager.getChildCount();
int totalItemCount = manager.getItemCount();
int[] firstVisibleItems = manager.findFirstVisibleItemPositions(null);
if (firstVisibleItems != null && firstVisibleItems.length > 0) {
pastVisibleItems = firstVisibleItems[0];
}
if (visibleItemCount + pastVisibleItems >= totalItemCount && !isLoading) {
isLoading = true;
if (hasMorePages && !isRefreshing) {
isRefreshing = true;
new Handler().postDelayed(new Runnable() {
@Override public void run() {
refreshList.onRefresh(pageNumber);
}
}, 200);
}
} else {
isLoading = false;
}
}
public void noMorePages() {
this.hasMorePages = false;
}
void notifyMorePages() {
isRefreshing = false;
pageNumber = pageNumber + 1;
}
interface RefreshList {
void onRefresh(int pageNumber);
} }
이 시도
위의 답변을 사용했는데 리사이클 러 뷰가 끝날 때 항상 실행됩니다.
바닥인지 아닌지 한 번만 확인하고 싶다면? 예 :-내가 아래로 갈 때마다 10 개 항목의 목록이있는 경우 나를 표시하고 위에서 아래로 스크롤하면 다시 인쇄되지 않으며 목록을 더 추가하고 거기로 가면 다시 표시됩니다.
참고 : -API 적중시 오프셋 을 처리 할 때이 방법을 사용하십시오 .
EndlessRecyclerViewScrollListener라는 이름의 클래스를 만듭니다.
import android.support.v7.widget.GridLayoutManager; import android.support.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import android.support.v7.widget.StaggeredGridLayoutManager; public abstract class EndlessRecyclerViewScrollListener extends RecyclerView.OnScrollListener { // The minimum amount of items to have below your current scroll position // before loading more. private int visibleThreshold = 5; // The current offset index of data you have loaded private int currentPage = 0; // The total number of items in the dataset after the last load private int previousTotalItemCount = 0; // True if we are still waiting for the last set of data to load. private boolean loading = true; // Sets the starting page index private int startingPageIndex = 0; RecyclerView.LayoutManager mLayoutManager; public EndlessRecyclerViewScrollListener(LinearLayoutManager layoutManager) { this.mLayoutManager = layoutManager; } // public EndlessRecyclerViewScrollListener() { // this.mLayoutManager = layoutManager; // visibleThreshold = visibleThreshold * layoutManager.getSpanCount(); // } public EndlessRecyclerViewScrollListener(StaggeredGridLayoutManager layoutManager) { this.mLayoutManager = layoutManager; visibleThreshold = visibleThreshold * layoutManager.getSpanCount(); } public int getLastVisibleItem(int[] lastVisibleItemPositions) { int maxSize = 0; for (int i = 0; i < lastVisibleItemPositions.length; i++) { if (i == 0) { maxSize = lastVisibleItemPositions[i]; } else if (lastVisibleItemPositions[i] > maxSize) { maxSize = lastVisibleItemPositions[i]; } } return maxSize; } // This happens many times a second during a scroll, so be wary of the code you place here. // We are given a few useful parameters to help us work out if we need to load some more data, // but first we check if we are waiting for the previous load to finish. @Override public void onScrolled(RecyclerView view, int dx, int dy) { int lastVisibleItemPosition = 0; int totalItemCount = mLayoutManager.getItemCount(); if (mLayoutManager instanceof StaggeredGridLayoutManager) { int[] lastVisibleItemPositions = ((StaggeredGridLayoutManager) mLayoutManager).findLastVisibleItemPositions(null); // get maximum element within the list lastVisibleItemPosition = getLastVisibleItem(lastVisibleItemPositions); } else if (mLayoutManager instanceof GridLayoutManager) { lastVisibleItemPosition = ((GridLayoutManager) mLayoutManager).findLastVisibleItemPosition(); } else if (mLayoutManager instanceof LinearLayoutManager) { lastVisibleItemPosition = ((LinearLayoutManager) mLayoutManager).findLastVisibleItemPosition(); } // If the total item count is zero and the previous isn't, assume the // list is invalidated and should be reset back to initial state if (totalItemCount < previousTotalItemCount) { this.currentPage = this.startingPageIndex; this.previousTotalItemCount = totalItemCount; if (totalItemCount == 0) { this.loading = true; } } // If it’s still loading, we check to see if the dataset count has // changed, if so we conclude it has finished loading and update the current page // number and total item count. if (loading && (totalItemCount > previousTotalItemCount)) { loading = false; previousTotalItemCount = totalItemCount; } // If it isn’t currently loading, we check to see if we have breached // the visibleThreshold and need to reload more data. // If we do need to reload some more data, we execute onLoadMore to fetch the data. // threshold should reflect how many total columns there are too if (!loading && (lastVisibleItemPosition + visibleThreshold) > totalItemCount) { currentPage++; onLoadMore(currentPage, totalItemCount, view); loading = true; } } // Call this method whenever performing new searches public void resetState() { this.currentPage = this.startingPageIndex; this.previousTotalItemCount = 0; this.loading = true; } // Defines the process for actually loading more data based on page public abstract void onLoadMore(int page, int totalItemsCount, RecyclerView view); }이 수업을 이렇게 사용하십시오
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(getActivity()); recyclerView.setLayoutManager(linearLayoutManager); recyclerView.addOnScrollListener(new EndlessRecyclerViewScrollListener( linearLayoutManager) { @Override public void onLoadMore(int page, int totalItemsCount, RecyclerView view) { Toast.makeText(getActivity(),"LAst",Toast.LENGTH_LONG).show(); } });
내 끝에서 완벽하게 달리고있어 문제가 생기면 칭찬 해줘
나는 또한이 질문을 찾고 있었지만 나를 만족시키는 답을 찾지 못했기 때문에 recyclerView의 자체 실현을 만듭니다.
다른 솔루션은 내 것보다 덜 정확합니다. 예를 들어, 마지막 항목이 꽤 큰 경우 (텍스트가 많음) 다른 솔루션의 콜백이 훨씬 일찍 올 것이고 recyclerView가 실제로 바닥에 도달했습니다.
내 해결책이이 문제를 해결합니다.
class CustomRecyclerView: RecyclerView{
abstract class TopAndBottomListener{
open fun onBottomNow(onBottomNow:Boolean){}
open fun onTopNow(onTopNow:Boolean){}
}
constructor(c:Context):this(c, null)
constructor(c:Context, attr:AttributeSet?):super(c, attr, 0)
constructor(c:Context, attr:AttributeSet?, defStyle:Int):super(c, attr, defStyle)
private var linearLayoutManager:LinearLayoutManager? = null
private var topAndBottomListener:TopAndBottomListener? = null
private var onBottomNow = false
private var onTopNow = false
private var onBottomTopScrollListener:RecyclerView.OnScrollListener? = null
fun setTopAndBottomListener(l:TopAndBottomListener?){
if (l != null){
checkLayoutManager()
onBottomTopScrollListener = createBottomAndTopScrollListener()
addOnScrollListener(onBottomTopScrollListener)
topAndBottomListener = l
} else {
removeOnScrollListener(onBottomTopScrollListener)
topAndBottomListener = null
}
}
private fun createBottomAndTopScrollListener() = object :RecyclerView.OnScrollListener(){
override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
checkOnTop()
checkOnBottom()
}
}
private fun checkOnTop(){
val firstVisible = linearLayoutManager!!.findFirstCompletelyVisibleItemPosition()
if(firstVisible == 0 || firstVisible == -1 && !canScrollToTop()){
if (!onTopNow) {
onTopNow = true
topAndBottomListener?.onTopNow(true)
}
} else if (onTopNow){
onTopNow = false
topAndBottomListener?.onTopNow(false)
}
}
private fun checkOnBottom(){
var lastVisible = linearLayoutManager!!.findLastCompletelyVisibleItemPosition()
val size = linearLayoutManager!!.itemCount - 1
if(lastVisible == size || lastVisible == -1 && !canScrollToBottom()){
if (!onBottomNow){
onBottomNow = true
topAndBottomListener?.onBottomNow(true)
}
} else if(onBottomNow){
onBottomNow = false
topAndBottomListener?.onBottomNow(false)
}
}
private fun checkLayoutManager(){
if (layoutManager is LinearLayoutManager)
linearLayoutManager = layoutManager as LinearLayoutManager
else
throw Exception("for using this listener, please set LinearLayoutManager")
}
private fun canScrollToTop():Boolean = canScrollVertically(-1)
private fun canScrollToBottom():Boolean = canScrollVertically(1)
}
그런 다음 활동 / 조각에서 :
override fun onCreate() {
customRecyclerView.layoutManager = LinearLayoutManager(context)
}
override fun onResume() {
super.onResume()
customRecyclerView.setTopAndBottomListener(this)
}
override fun onStop() {
super.onStop()
customRecyclerView.setTopAndBottomListener(null)
}
누군가를 hepl하기를 바랍니다 ;-)
이것은 내 해결책입니다.
val onScrollListener = object : RecyclerView.OnScrollListener() {
override fun onScrolled(recyclerView: RecyclerView?, dx: Int, dy: Int) {
directionDown = dy > 0
}
override fun onScrollStateChanged(recyclerView: RecyclerView, newState: Int) {
if (recyclerView.canScrollVertically(1).not()
&& state != State.UPDATING
&& newState == RecyclerView.SCROLL_STATE_IDLE
&& directionDown) {
state = State.UPDATING
// TODO do what you want when you reach bottom, direction
// is down and flag for non-duplicate execution
}
}
}
위치를 얻기 위해 인터페이스를 사용할 수 있습니다.
Interface : 리스너 용 인터페이스 생성
public interface OnTopReachListener { void onTopReached(int position);}
활동 :
mediaRecycleAdapter = new MediaRecycleAdapter(Class.this, taskList); recycle.setAdapter(mediaRecycleAdapter); mediaRecycleAdapter.setOnSchrollPostionListener(new OnTopReachListener() {
@Override
public void onTopReached(int position) {
Log.i("Position","onTopReached "+position);
}
});
어댑터 :
public void setOnSchrollPostionListener(OnTopReachListener topReachListener) {
this.topReachListener = topReachListener;}@Override public void onBindViewHolder(MyViewHolder holder, int position) {if(position == 0) {
topReachListener.onTopReached(position);}}
수평 LinearLayoutManager (Kotlin)에 대한 내 솔루션 :
recyclerView.addOnScrollListener(object : RecyclerView.OnScrollListener() {
override fun onScrolled(recyclerView: RecyclerView, dx:Int, dy: Int) {
super.onScrolled(recyclerView, dx, dy)
if (dx == 0 && !recyclerView.canScrollHorizontally(1)) {
//add here your code
recyclerView.removeOnScrollListener(this)//remove this listener to prevent leaks
}
}
})
recyclerView.layoutManager?.scrollToPosition(recyclerView.adapter?.itemCount?.minus(1)!!)//scroll to last item position to trigger OnScrollListener
위의 답변으로 완벽한 솔루션을 얻지 못했습니다. onScrolled
override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
super.onScrolled(recyclerView, dx, dy)
if( !recyclerView.canScrollVertically(RecyclerView.FOCUS_DOWN))
context?.toast("Scroll end reached")
}
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