I'd like to scroll to the bottom of the RecyclerView list after loading the activity.
GENERIC_MESSAGE_LIST = (ArrayList) intent.getExtras().getParcelableArrayList(ConversationsAdapter.EXTRA_MESSAGE);
conversationView = (RecyclerView) findViewById(R.id.list_messages);
conversationView.setHasFixedSize(true);
conversationViewLayoutManager = new LinearLayoutManager(this);
conversationView.setLayoutManager(conversationViewLayoutManager);
conversationViewAdapter = new ConversationAdapter(GENERIC_MESSAGE_LIST, this);
conversationView.setAdapter(conversationViewAdapter);
conversationView.scrollTo(...)
throws an exception about being not supported in RecyclerView, and conversationView.scrollToPosition(...)
doesn't seem to do anything.
After the above block of code, I added
conversationView.scrollToPosition(GENERIC_MESSAGE_LIST.size() + 1)
which doesn't work. There are 30 elements in GENERIC_MESSAGE_LIST
.
scrollToPosition
immediately after setting the adapter?
conversationView.setAdapter(conversationViewAdapter);
.
I was looking at this post to find the answer but... I think everyone on this post was facing the same scenario as me: scrollToPosition()
was fully ignored, for an evident reason.
What I was using?
recyclerView.scrollToPosition(items.size());
... what WORKED?
recyclerView.scrollToPosition(items.size() - 1);
Just set setStackFromEnd=true
or setReverseLayout=true
so that LLM will layout items from end.
The difference between these two is that setStackFromEnd
will set the view to show the last element, the layout direction will remain the same. (So, in an left-to-right horizontal Recycler View, the last element will be shown and scrolling to the left will show the earlier elements)
Whereas setReverseLayout
will change the order of the elements added by the Adapter. The layout will start from the last element, which will be the left-most in an LTR Recycler View and then, scrolling to the right will show the earlier elements.
Sample:
final LinearLayoutManager linearLayoutManager = new LinearLayoutManager(getActivity());
linearLayoutManager.setReverseLayout(true);
_listView.setLayoutManager(linearLayoutManager);
See documentation for details.
I know its late to answer here, still if anybody want to know solution is below
conversationView.smoothScrollToPosition(conversationView.getAdapter().getItemCount() - 1);
conversationView.smoothScrollToPosition(conversationView.getAdapter().getItemCount() **-1**);
as positions in lists are zero-based.
To scrolldown from any position in the recyclerview to bottom
Kotlin
editText.setOnClickListener {
rv.postDelayed({
rv.scrollToPosition(rv.adapter.itemCount - 1)
}, 1000)
}
Java
edittext.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
rv.postDelayed(new Runnable() {
@Override
public void run() {
rv.scrollToPosition(rv.getAdapter().getItemCount() - 1);
}
}, 1000);
}
});
Add this code after sending message and before getting message from server
recyclerView.scrollToPosition(mChatList.size() - 1);
When you call setAdapter
, that does not immediately lay out and position items on the screen (that takes a single layout pass) hence your scrollToPosition()
call has no actual elements to scroll to when you call it.
Instead, you should register a ViewTreeObserver.OnGlobalLayoutListener (via addOnGlobalLayoutListner() from a ViewTreeObserver
created by conversationView.getViewTreeObserver()
) which delays your scrollToPosition()
until after the first layout pass:
conversationView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
public void onGlobalLayout() {
conversationView.scrollToPosition(GENERIC_MESSAGE_LIST.size();
// Unregister the listener to only call scrollToPosition once
conversationView.getViewTreeObserver().removeGlobalOnLayoutListener(this);
// Use vto.removeOnGlobalLayoutListener(this) on API16+ devices as
// removeGlobalOnLayoutListener is deprecated.
// They do the same thing, just a rename so your choice.
}
});
OnGlobalLayoutListener
probably not getting removed because you're checking for vto.isAlive()
. I don't know the reason, but ViewTreeObserver
sometimes is changed for a View
, so instead of checking for isAlive
you better just get current ViewTreeObserver
with conversationView.getViewTreeObserver().removeGlobalOnLayoutListener
Solution for Kotlin:
apply below code after setting "recyclerView.adapter" or after "recyclerView.adapter.notifyDataSetChanged()"
recyclerView.scrollToPosition(recyclerView.adapter.itemCount - 1)
IF you have adapter attached with recyclerView then just do this.
mRecyclerView.smoothScrollToPosition(mRecyclerView.getAdapter().getItemCount());
The answer is
recyclerView.scrollToPosition(arrayList.size() - 1);
Everyone has mentioned it.
But the problem I was facing was that it was not placed correctly.
I tried and placed just after the adapter.notifyDataSetChanged();
and it worked. Whenever, data in your recycler view changes, it automatically scrolls to the bottom like after sending messages or you open the chat list for the first time.
Note : This code was tasted in Java.
actual code for me was :
//scroll to bottom after sending message.
binding.chatRecyclerView.scrollToPosition(messageArrayList.size() - 1);
class MyLayoutManager extends LinearLayoutManager {
public MyLayoutManager(Context context) {
super(context, LinearLayoutManager.VERTICAL, false);
}
@Override public void smoothScrollToPosition(RecyclerView recyclerView,
final RecyclerView.State state, final int position) {
int fcvip = findFirstCompletelyVisibleItemPosition();
int lcvip = findLastCompletelyVisibleItemPosition();
if (position < fcvip || lcvip < position) {
// scrolling to invisible position
float fcviY = findViewByPosition(fcvip).getY();
float lcviY = findViewByPosition(lcvip).getY();
recyclerView.setOnScrollListener(new RecyclerView.OnScrollListener() {
int currentState = RecyclerView.SCROLL_STATE_IDLE;
@Override public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
if (currentState == RecyclerView.SCROLL_STATE_SETTLING
&& newState == RecyclerView.SCROLL_STATE_IDLE) {
// recursive scrolling
smoothScrollToPosition(recyclerView, state, position);
}
currentState = newState;
}
@Override public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
int fcvip = findFirstCompletelyVisibleItemPosition();
int lcvip = findLastCompletelyVisibleItemPosition();
if ((dy < 0 && fcvip == position) || (dy > 0 && lcvip == position)) {
// stop scrolling
recyclerView.setOnScrollListener(null);
}
}
});
if (position < fcvip) {
// scroll up
recyclerView.smoothScrollBy(0, (int) (fcviY - lcviY));
} else {
// scroll down
recyclerView.smoothScrollBy(0, (int) (lcviY - fcviY));
}
} else {
// scrolling to visible position
float fromY = findViewByPosition(fcvip).getY();
float targetY = findViewByPosition(position).getY();
recyclerView.smoothScrollBy(0, (int) (targetY - fromY));
}
}
}
and
MyLayoutManager layoutManager = new MyLayoutManager(context);
recyclerView.setLayoutManager(layoutManager);
RecyclerView.Adapter adapter = new YourAdapter();
recyclerView.setAdapter(adapter);
recyclerView.smoothScrollToPosition(adapter.getItemCount() - 1);
above code works, but it's not smooth and not cool.
In Kotlin:
recyclerView.viewTreeObserver.addOnGlobalLayoutListener { scrollToEnd() }
private fun scrollToEnd() =
(adapter.itemCount - 1).takeIf { it > 0 }?.let(recyclerView::smoothScrollToPosition)
GlobalLayoutListener
! After refactoring I had to use your method to scroll. Don't forget to remove the listener like in stackoverflow.com/questions/28264139/…, or you won't scroll RecyclerView back to beginning.
Roc answer is a great help. I would like to add a small block to it:
mRecyclerView.scrollToPosition(mAdapter.getItemCount() - 1);
In my case where views do not have the same height, calling scrollToPosition on the LayoutManager worked to really scroll to the bottom and see fully the last item:
recycler.getLayoutManager().scrollToPosition(adapter.getItemCount() - 1);
If you are having issues making recyclerview scroll to the latest, check that the recyclerview is not inside a nestedScrollView. That was my issue. I had to remove the nestedScrollview and then the below code worked.
binding.recyclerView.scrollToPosition(adapter.getItemCount() - 1);
First time scroll when entering in recycler view first time then use
linearLayoutManager.scrollToPositionWithOffset(messageHashMap.size()-1
put in minus for scroll down for scroll up put in positive value);
if the view is very big in height then scrolltoposition particular offset is used for the top of view then you use
int overallXScroldl =chatMessageBinding.rvChat.computeVerticalScrollOffset();
chatMessageBinding.rvChat.smoothScrollBy(0, Math.abs(overallXScroldl));
This works perfectly fine for me:
AdapterChart adapterChart = new AdapterChart(getContext(),messageList);
recyclerView.setAdapter(adapterChart);
recyclerView.scrollToPosition(recyclerView.getAdapter().getItemCount()-1);
this code will give you latest post first, i think this answer is helpful.
mInstaList=(RecyclerView)findViewById(R.id.insta_list);
mInstaList.setHasFixedSize(true);
LinearLayoutManager layoutManager = new LinearLayoutManager(this);
layoutManager.setOrientation(LinearLayoutManager.VERTICAL);
mInstaList.setLayoutManager(layoutManager);
layoutManager.setStackFromEnd(true);
layoutManager.setReverseLayout(true);
Tried a method of @galex, it worked until refactoring. So I used an answer of @yanchenko and changed a bit. Probably this is because I called scrolling from onCreateView()
, where a fragment view was built (and probably didn't have right size).
private fun scrollPhotosToEnd(view: View) {
view.recycler_view.viewTreeObserver.addOnGlobalLayoutListener(object :
ViewTreeObserver.OnGlobalLayoutListener {
override fun onGlobalLayout() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
view.recycler_view.viewTreeObserver.removeOnGlobalLayoutListener(this)
} else {
@Suppress("DEPRECATION")
view.recycler_view.viewTreeObserver.removeGlobalOnLayoutListener(this)
}
adapter?.itemCount?.takeIf { it > 0 }?.let {
view.recycler_view.scrollToPosition(it - 1)
}
}
})
}
You can also add a check of viewTreeObserver.isAlive
like in https://stackoverflow.com/a/39001731/2914140.
You must hide AppBarLayout
before scrollToPosition
if you are using him
You can scroll to the bottom of the last item, if the height of the last item is too large, you need to offset
private void scrollToBottom(final RecyclerView recyclerView) {
// scroll to last item to get the view of last item
final LinearLayoutManager layoutManager = (LinearLayoutManager) recyclerView.getLayoutManager();
final RecyclerView.Adapter adapter = recyclerView.getAdapter();
final int lastItemPosition = adapter.getItemCount() - 1;
layoutManager.scrollToPositionWithOffset(lastItemPosition, 0);
recyclerView.post(new Runnable() {
@Override
public void run() {
// then scroll to specific offset
View target = layoutManager.findViewByPosition(lastItemPosition);
if (target != null) {
int offset = recyclerView.getMeasuredHeight() - target.getMeasuredHeight();
layoutManager.scrollToPositionWithOffset(lastItemPosition, offset);
}
}
});
}
I know this is too late but this worked for me so that i am answering this question
first,
LinearLayoutManager layoutManager=new LinearLayoutManager(this);
layoutManager.setStackFromEnd(true);
recyclerView.setLayoutManager(layoutManager);
after that,
database.addValueEventListener(....){
@override
public void onDataCange(...){
....
....
//put this line here
recyclerView.smoothScrollToPosition(recyclerView.getAdapter().getItemCount()-1);
}
}
if you use kotlin, try this
conversationView.post {
scrollToPosition(conversationView?.adapter.itemCount - 1)
}
Only Ian's answer was able to make my RecyclerView
scroll to a specified position. However, The RecyclerView
was not able to scroll afterwards when I used scrollToPosition()
. smoothScrollToPosition()
worked but the initial animation made it too slow when the list was long. The reason was the listener was not removed. I used the code below to remove the current ViewTreeObserver
and it worked as a charm.
mRecyclerView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {
mRecyclerView.scrollToPosition(mPosition);
mRecyclerView.getViewTreeObserver().removeOnGlobalLayoutListener(this);
}
});
If none of these worked,
you should try to use :
ConstraintLayout targetView = (ConstraintLayout) recyclerView.findViewHolderForAdapterPosition(adapter.getItemCount()-1).itemView;
targetView.getParent().requestChildFocus(targetView, targetView);
By doing this, you are requesting a certain ConstraintLayout (Or whatever you have) to be displayed. The scroll is instant.
I works even with keyboard shown.
If you want just starting from the end use:
layoutManager.stackFromEnd = true
(Kotlin solution)
If you working with reversedLayout "chat interface" specially if you have images, you can try the following:
first, register DataObserver with the adapter
chatAdapter.registerAdapterDataObserver(object :
RecyclerView.AdapterDataObserver() {
override fun onItemRangeInserted(positionStart: Int itemCount: Int) {
val messageCount: Int = chatAdapter.itemCount
val lastVisiblePosition: Int =
layoutManager.findLastCompletelyVisibleItemPosition()
if (lastVisiblePosition == -1 || positionStart <= (messageCount - 1)) {
recyclerView.scrollToPosition(positionStart)
}
}
})
this will be called once you set the data for the adapter
second, you have to add a scroll listener to the recyclerView like this:
recyclerView.addOnScrollListener(object
:RecyclerView.OnScrollListener() {
override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy:
Int) {
super.onScrolled(recyclerView, dx, dy)
val lastVisiblePosition: Int =
layoutManager.findLastCompletelyVisibleItemPosition()
if (lastVisiblePosition != -1 && lastVisiblePosition <
chatAdapter.itemCount - 1) {
recyclerView.smoothScrollToPosition(0)
}
}
})
use only gravity for easy solution
android:layout_gravity="bottom"
Success story sharing
recyclerView.scrollToPosition(messages.size()-1);
really works for me, I just wonder the reason.smoothScrollToPosition(...)
.