How to know whether a RecyclerView / LinearLayoutManager is scrolled to top or bottom?
AndroidAndroid RecyclerviewAndroid Problem Overview
Currently I am using the follow code to check whether SwipeRefreshLayout should be enabled.
private void laySwipeToggle() {
if (mRecyclerView.getChildCount() == 0 || mRecyclerView.getChildAt(0).getTop() == 0) {
mLaySwipe.setEnabled(true);
} else {
mLaySwipe.setEnabled(false);
}
}
But here is the problem. When it's scrolled to another item's view's boundary mRecyclerView.getChildAt(0).getTop()
also returns 0.
Is there something like RecyclerView.isScrolledToBottom()
or RecyclerView.isScrolledToTop()
?
EDIT: (mRecyclerView.getChildAt(0).getTop() == 0 && linearLayoutManager.findFirstVisibleItemPosition() == 0)
kind of does the RecyclerView.isScrolledToTop()
, but what about RecyclerView.isScrolledToBottom()
?
Android Solutions
Solution 1 - Android
The solution is in the layout manager.
LinearLayoutManager layoutManager = new LinearLayoutManager(this);
// Add this to your Recycler view
recyclerView.setLayoutManager(layoutManager);
// To check if at the top of recycler view
if(layoutManager.firstCompletelyVisibleItemPosition()==0){
// Its at top
}
// To check if at the bottom of recycler view
if(layoutManager.lastCompletelyVisibleItemPosition()==data.size()-1){
// Its at bottom
}
EDIT
In case your item size is larger than the screen use the following to detect the top event.
RecyclerView recyclerView = (RecyclerView) view;
LinearLayoutManager linearLayoutManager = (LinearLayoutManager) recyclerView.getLayoutManager();
int pos = linearLayoutManager.findFirstVisibleItemPosition();
if(linearLayoutManager.findViewByPosition(pos).getTop()==0 && pos==0){
return true;
}
PS: Actually, if you place the RecyclerView
directly inside the SwipeRefreshview
you wouldn't need to do this
Solution 2 - Android
You can try recyclerView.canScrollVertically(int direction)
, if you just need to know whether it possible to scroll or not.
Direction integers:
- -1 for up
- 1 for down
- 0 will always return false.
Solution 3 - Android
In order to check whether RecyclerView
is scrolled to bottom. Use the following code.
/**
* Check whether the last item in RecyclerView is being displayed or not
*
* @param recyclerView which you would like to check
* @return true if last position was Visible and false Otherwise
*/
private boolean isLastItemDisplaying(RecyclerView recyclerView) {
if (recyclerView.getAdapter().getItemCount() != 0) {
int lastVisibleItemPosition = ((LinearLayoutManager) recyclerView.getLayoutManager()).findLastCompletelyVisibleItemPosition();
if (lastVisibleItemPosition != RecyclerView.NO_POSITION && lastVisibleItemPosition == recyclerView.getAdapter().getItemCount() - 1)
return true;
}
return false;
}
Some Additional info
If you want to implement ScrollToBottom
in RecyclerView
when Edittext
is tapped
then i recommend you add 1 second delay like this:
edittext.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_UP)
if (isLastItemDisplaying(recyclerView)) {
// The scrolling can happen instantly before keyboard even opens up so to handle that we add 1 second delay to scrolling
recyclerView.postDelayed(new Runnable() {
@Override
public void run() {
recyclerView.smoothScrollToPosition(recyclerView.getAdapter().getItemCount() - 1);
}
}, 1000);
}
return false;
}
});
Solution 4 - Android
@Saren Arterius, Using the addOnScrollListener of RecycleView, you can find the scrolling top or bottom of Vertical RecycleView like below,
RecyclerView rv = (RecyclerView)findViewById(R.id.rv);
rv.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
}
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
if (dy < 0) {
// Recycle view scrolling up...
} else if (dy > 0) {
// Recycle view scrolling down...
}
}
});
Solution 5 - Android
Use recyclerView.canScrollVertically(int direction) to check if top or bottom of the scroll reached.
direction = 1 for scroll down (bottom)
direction = -1 for scroll up (top)
if method return false that means you reached either top or bottom depends on the direction.
Solution 6 - Android
Just keep a reference to your layoutManager and set onScrollListener on your recycler view like this
mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
visibleItemCount = mRecyclerView.getChildCount();
totalItemCount = mLayoutManager.getItemCount();
firstVisibleItemIndex = mLayoutManager.findFirstVisibleItemPosition();
//synchronizew loading state when item count changes
if (loading) {
if (totalItemCount > previousTotal) {
loading = false;
previousTotal = totalItemCount;
}
}
if (!loading)
if ((totalItemCount - visibleItemCount) <= firstVisibleItemIndex) {
// Loading NOT in progress and end of list has been reached
// also triggered if not enough items to fill the screen
// if you start loading
loading = true;
} else if (firstVisibleItemIndex == 0){
// top of list reached
// if you start loading
loading = true;
}
}
}
});
Solution 7 - Android
you can do this it's work for me
mRecycleView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
}
}
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
int topRowVerticalPosition = (recyclerView == null || recyclerView.getChildCount() == 0) ?
0 : recyclerView.getChildAt(0).getTop();
LinearLayoutManager linearLayoutManager1 = (LinearLayoutManager) recyclerView.getLayoutManager();
int firstVisibleItem = linearLayoutManager1.findFirstVisibleItemPosition();
swipeRefreshLayout.setEnabled(firstVisibleItem == 0 && topRowVerticalPosition >= 0);
}
});
Solution 8 - Android
You can detect top by using the following
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
}
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
if(isRecyclerViewAtTop())
{
//your recycler view reached Top do some thing
}
}
});
private boolean isRecyclerViewAtTop() {
if(recyclerView.getChildCount() == 0)
return true;
return recyclerView.getChildAt(0).getTop() == 0;
}
This will detect top when you release the finger once reached top,
if you want to detect as soon the reacyclerview reaches top check if(isRecyclerViewAtTop())
inside onScrolled
method
Solution 9 - Android
I have written a RecyclerViewHelper to know the recyclerview is at top or at bottom.
public class RecyclerViewHelper {
public static boolean isAtTop(RecyclerView recyclerView) {
if (android.os.Build.VERSION.SDK_INT < Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
return isAtTopBeforeIceCream(recyclerView);
} else {
return !ViewCompat.canScrollVertically(recyclerView, -1);
}
}
private static boolean isAtTopBeforeIceCream(RecyclerView recyclerView) {
RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();
if (layoutManager instanceof LinearLayoutManager) {
LinearLayoutManager linearLayoutManager = (LinearLayoutManager) layoutManager;
int pos = linearLayoutManager.findFirstVisibleItemPosition();
if (linearLayoutManager.findViewByPosition(pos).getTop() == recyclerView.getPaddingTop() && pos == 0)
return true;
}
return false;
}
public static boolean isAtBottom(RecyclerView recyclerView) {
if (android.os.Build.VERSION.SDK_INT < Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
return isAtBottomBeforeIceCream(recyclerView);
} else {
return !ViewCompat.canScrollVertically(recyclerView, 1);
}
}
private static boolean isAtBottomBeforeIceCream(RecyclerView recyclerView) {
RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();
int count = recyclerView.getAdapter().getItemCount();
if (layoutManager instanceof LinearLayoutManager) {
LinearLayoutManager linearLayoutManager = (LinearLayoutManager) layoutManager;
int pos = linearLayoutManager.findLastVisibleItemPosition();
int lastChildBottom = linearLayoutManager.findViewByPosition(pos).getBottom();
if (lastChildBottom == recyclerView.getHeight() - recyclerView.getPaddingBottom() && pos == count - 1)
return true;
}
return false;
}
}
Solution 10 - Android
To find out if the RecyclerView is scrolled to bottom, you could reuse the methods used for the scrollbar.
This is the calculation, for convenience written as a Kotlin extension function:
fun RecyclerView.isScrolledToBottom(): Boolean {
val contentHeight = height - (paddingTop + paddingBottom)
return computeVerticalScrollRange() == computeVerticalScrollOffset() + contentHeight
}
Solution 11 - Android
If you're still looking for an answer in 2022, here you go:
mRecyclerView.setOnScrollChangeListener((view, i, i1, i2, i3) -> {
if(!mRecyclerView.canScrollVertically(RecyclerView.FOCUS_DOWN)){
// reached the bottom of the list, load more data
}
});
Solution 12 - Android
you can try with the OnTouchListener:
recyclerView.addOnItemTouchListener(new RecyclerView.OnItemTouchListener() {
@Override
public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {
if (e.getAction() == MotionEvent.ACTION_UP
|| e.getAction() == MotionEvent.ACTION_MOVE){
if (mLinearLayoutManager.findFirstCompletelyVisibleItemPosition() > 0)
{
// beginning of the recycler
}
if (mLinearLayoutManager.findLastCompletelyVisibleItemPosition()+1 < recyclerView.getAdapter().getItemCount())
{
// end of the recycler
}
}
return false;
}