I have this code addOnScrollListener of recyclerview which is inside a nestedscroll view
mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
mScrollState = newState;
if (newState == RecyclerView.SCROLL_STATE_IDLE && adapter.getItemCount() > 0) {
mCalculator.onScrollStateIdle();
}
}
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
mCalculator.onScrolled(mScrollState);
}
});
i need to get into those methods in addOnScrollListener when i scroll my view.
But unfortunately, while scrolling not entering this methods. can anyone help me
how to get scroll of recyclerview inside the nested scrollview
behalf of new RecyclerView.OnScrollListener() try to use NestedScrollView.OnScrollChangeListener. It might be help you to solved your issue
nestedScrollView.setOnScrollChangeListener((NestedScrollView.OnScrollChangeListener) (v, x, y, x1, y1) -> {
if(v.getChildAt(v.getChildCount() - 1) != null) {
if ((x >= (v.getChildAt(v.getChildCount() - 1).getMeasuredHeight() - v.getMeasuredHeight())) &&
y > y1) {
//code to fetch more data for endless scrolling
}
}
});
I just handled issue by using gesture motion
Related
I have a RecyclerView with Horizontal LinearLayoutManager.
I would like to check ScrollListener.
My goal is to check these steps:
Check when RecyclerView start scroll
Check when RecyclerView end scroll
Check when RecyclerView's scroll is in center position
Here is a my RecyclerView code with LinearLayoutManager.
LinearLayoutManager horizontalManager = new LinearLayoutManager(context);
horizontalManager.setOrientation(LinearLayoutManager.HORIZONTAL);
viewHolderStory.recyclerView.setLayoutManager(horizontalManager);
viewHolderStory.recyclerView.addItemDecoration(new PaddingItemDecoration((Activity) context));
viewHolderStory.recyclerView.setHasFixedSize(true);
viewHolderStory.recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
}
});
viewHolderStory.recyclerView.setNestedScrollingEnabled(false);
Is any way to add validation on my addOnScrollListener method?
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
if(newState==RecyclerView.SCROLL_STATE_IDLE){
/// User Stops Scroll
}
if(newState==RecyclerView.SCROLL_STATE_DRAGGING){
/// User Starts Scroll
}
}
You can find more from this.
You can compute this with computeVerticalScrollExtent() , computeVerticalScrollOffset() and computeVerticalScrollRange()
if your recyler view is horizontal, these functions have a horizontal counterpart
full code :
viewHolderStory.recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener()
{
#Override
public void onScrolled(#NonNull RecyclerView recyclerView, int dx, int dy) {
int extent = recyclerView.computeVerticalScrollExtent();
int offset = recyclerView.computeVerticalScrollOffset();
int range = recyclerView.computeVerticalScrollRange();
if(offset == 0){
//fire when recycler view hit top
Log.i("myTag", "onScrolled: top");
}
else if(offset + extent == range){
//fire when recycler view hit bottom
Log.i("myTag", "onScrolled: bottom");
}
else {
//fire the rest of the time
Log.i("myTag", "onScrolled: middle");
}
}
});
I have a recycleView that I need to observe when the last item is reached but I have notice the it always indicate that I reached the last item even if I haven't scrolled yet.
My code for setting up the recycler:
newsRecyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
newsRecyclerView.setFocusable(false);
newsRecyclerView.setNestedScrollingEnabled(false);
newsAdapter = new NewsAdapter(getContext(), newsDetails, categoryNumber);
newsRecyclerView.setAdapter(newsAdapter);
layoutManager = new LinearLayoutManager(getContext(), LinearLayoutManager.VERTICAL, false);
My xml code is:
<android.support.v7.widget.RecyclerView
android:id="#+id/news_recycler_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="4dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/news_top_stories_title_text_view" />
This is my code that I put in my Util, and use anywhere.
Util.setRecyclerViewLastPositionListner(rv, linearLayoutManager , new UtilitiesV2.OnLastPositionReached() {
#Override
public void onReached() {
// last position reached
}
});
Put this in Util.
private boolean userScrolled = true;
int pastVisiblesItems, visibleItemCount, totalItemCount;
public interface OnLastPositionReached {
void onReached();
}
public void setRecyclerViewLastPositionListner(RecyclerView rvBooksMockTest, final LinearLayoutManager mLayoutManager, final OnLastPositionReached onLastPositionReached) {
rvBooksMockTest.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
if (newState == AbsListView.OnScrollListener.SCROLL_STATE_TOUCH_SCROLL) {
userScrolled = true;
}
}
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
// Here get the child count, item count and visibleitems
// from layout manager
visibleItemCount = mLayoutManager.getChildCount();
totalItemCount = mLayoutManager.getItemCount();
pastVisiblesItems = mLayoutManager.findFirstVisibleItemPosition();
// Now check if userScrolled is true and also check if
// the item is end then update recycler view and set
// userScrolled to false
if (userScrolled && (visibleItemCount + pastVisiblesItems) == totalItemCount) {
userScrolled = false;
if (onLastPositionReached != null) onLastPositionReached.onReached();
}
}
});
}
Update
According to your requirement, here is NestedScrollView bottom reach listener.
nestedScrollView.getViewTreeObserver().addOnScrollChangedListener(new ViewTreeObserver.OnScrollChangedListener() {
#Override
public void onScrollChanged() {
if (nestedScrollView != null) {
if (nestedScrollView.getChildAt(0).getBottom() <= (nestedScrollView.getHeight() + nestedScrollView.getScrollY())) {
//scroll view is at bottom
} else {
//scroll view is not at bottom
}
}
}
});
Thanks to Khemraj who give the tip for solution
because I have a recyclerview inside NestedScrollView and coordinator layout as parent for them
I have solved my problem like this:
public Disposable observeNestedScroll(LoadMoreListener listener) {
return RxNestedScrollView.scrollChangeEvents(nestedScrollView)
.subscribe(
viewScrollChangeEvent -> {
NestedScrollView nestedScrollView =(NestedScrollView) viewScrollChangeEvent.view();
if(nestedScrollView.getChildAt(nestedScrollView.getChildCount() - 1) != null) {
if ((viewScrollChangeEvent.scrollY() >= (nestedScrollView.getChildAt(nestedScrollView.getChildCount() - 1).getMeasuredHeight() - nestedScrollView.getMeasuredHeight())) &&
viewScrollChangeEvent.scrollY() > viewScrollChangeEvent.oldScrollY()) {
listener.onLoadMore();
}
}
});
}
I've seen to many responses for this question and I stand that all of them don't give accurate behavior as an outcome. However if you follow this approach I'm positive you'll get the best behavior.
rvCategories is your RecyclerView
categoriesList is the list passed to your adapter
binding.rvCategories.addOnScrollListener(object : RecyclerView.OnScrollListener() {
override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
val position = (recyclerView.layoutManager as LinearLayoutManager).findLastCompletelyVisibleItemPosition()
if (position + 1 == categoriesList.size) {
// END OF RECYCLERVIEW IS REACHED
} else {
// END OF RECYCLERVIEW IS NOT REACHED
}
}
})
I have included RecyclerView inside NestedScrollView and set
mRecyclerView.setNestedScrollingEnabled(false);
Since the scrolling of RecyclerView is set to false, I will not get the scroll position of RecyclerView due to this I will not be able to put pagination in RecyclerView.
I have also tried this
mRecylerview.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) {
totalItemCount = linearLayoutManager.getItemCount();
lastVisibleItem = linearLayoutManager.findLastVisibleItemPosition();
if (!isLoading && totalItemCount <= (lastVisibleItem + visibleThreshold)) {
// End has been reached
// Do something
if (mOnLoadMoreListener != null) {
mOnLoadMoreListener.onLoadMore();
isLoading = true;
}
}
}
}
});
But here lastVisibleItem always gives the length of the list to be displayed.
After few digging, I found that when we use RecylerView inside NestedScrollView all the view gets created at the very beginning so that's the reason why lastVisibleItem always gives the size of the list.
Or if I am wrong please explain, me how RecyclerView inside NestedScrollView works?.
Is there any workaround so that I can get RecyclerView scroll position so that I can make my pagination work?.
It will be a great help. Thanks in advance
Here scroll is NestedScrollView
scroll.getViewTreeObserver().addOnScrollChangedListener(() -> {
View view = (View) scroll.getChildAt(scroll.getChildCount() - 1);
Log.d("CategoryNeswList", scroll.getChildCount() + " child");
int diff = (view.getBottom() - (scroll.getHeight() + scroll
.getScrollY()));
if (diff == 0) {
// getPlaylistFromServer("more");
Toast.makeText(mContext, "Load More", Toast.LENGTH_SHORT).show();
}
});
Basically I want my recyclerview to automatically scroll to a position where the item is not half shown. Like the one in googleplay.
I have written a code
public void scrollToVisible(){
int firstVisibleItemPosition = ((LinearLayoutManager) recyclerView.getLayoutManager()).findFirstVisibleItemPosition();
View view = recyclerView.getLayoutManager().getChildAt(0);
if (firstVisibleItemPosition > 0 && view != null) {
int offsetTop = view.getTop();
if (firstVisibleItemPosition - 1 >= 0 && adapter.getItemCount() > 0) {
((LinearLayoutManager) recyclerView.getLayoutManager()).scrollToPositionWithOffset(firstVisibleItemPosition - 1, offsetTop);
}
}
}
The problem comes next. I dont know where to put this code. I have a vague idea to put it when the recyclerview stops on scrolling but I've been searching for quite some time now and i cant find such a method. when i put it on the onScroll some unexpected behavior comes out
You may create a CustomRecyclerView extending RecyclerView
public class CustomRecyclerView extends RecyclerView {
#Override
public void onScrollStateChanged(int state) {
super.onScrollStateChanged(state);
// check if scrolling has stopped
if (state == SCROLL_STATE_IDLE) {
LinearLayoutManager linearLayoutManager = (LinearLayoutManager) getLayoutManager();
// use code here
}
}
If it maybe of any help to someone:
mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
Log.d("y value",String.valueOf(dy));
if (dy > 0) {
//scrolling up
} else {
// Scrolling down
}
}
#Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
if (newState == AbsListView.OnScrollListener.SCROLL_STATE_FLING) {
// Do something
Log.e("SCROLL_STATE_FLING","SCROLL_STATE_FLING");
} else if (newState == AbsListView.OnScrollListener.SCROLL_STATE_TOUCH_SCROLL) {
Log.e("SCROLLTOUCH_SCROLL","SCROLL_STATE_TOUCH_SCROLL");
//slideUp(party_view);
// Do something
} else if (newState==AbsListView.OnScrollListener.SCROLL_STATE_IDLE){
// Do something
//slideDown(party_view);
Log.e("SCROLL_STATE_IDLE","SCROLL_STATE_IDLE");
}
}
});
complete example with UI synchronization
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrollStateChanged(#NonNull RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
Handler handler = new Handler(getMainLooper());
if (newState == 0) {
handler.removeCallbacks(MainActivity.this::hideFab);
handler.postDelayed(MainActivity.this::showFab, 400);
} else {
handler.removeCallbacks(MainActivity.this::showFab);
handler.postDelayed(MainActivity.this::hideFab, 100);
}
}
});
private void hideFab() {
addFile.hide();
addText.hide();
camera.hide();
}
private void showFab() {
addFile.show();
addText.show();
camera.show();
}
I want to implement pagination with recyclerView, for this I add addOnScrollListener to the recyclerView but I am having trouble with RecyclerView.OnScrollListener not working when I set rvGridExplore.setNestedScrollingEnabled(false);
But when I remove rvGridExplore.setNestedScrollingEnabled(false); it is working fine,
I don't know how to handle this.
Here is code:
rvGridExplore = (RecyclerView) view.findViewById(R.id.rvGridExplore);
final GridLayoutManager glm = new GridLayoutManager(context,2);
// rvGridExplore.setNestedScrollingEnabled(false);
rvGridExplore.setLayoutManager(glm);
// final int visibleItemCount,totalCount,pastVisibleItems;
rvGridExplore.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
Log.v("scrollll","state changed");
}
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
if (dy > 0) {
int totalCount = glm.getItemCount();
int visibleItemCount = glm.getChildCount();
int pastVisibleItems = glm.findFirstVisibleItemPosition();
if (loading) {
if ((visibleItemCount + pastVisibleItems) >= totalCount) {
Log.v("scroll","scrolled"+pastVisibleItems);
}
}
}
}
});
Do add setOnScrollChangeListner to your NestedScrollView
nestedScrollview.setOnScrollChangeListener(new NestedScrollView.OnScrollChangeListener() {
#Override
public void onScrollChange(NestedScrollView v, int scrollX, int scrollY, int oldScrollX, int oldScrollY) {
if (scrollY == (v.getChildAt(0).getMeasuredHeight() - v.getMeasuredHeight())) {
if(loading)
onClick();
loading=false;
}
}
});
after loading data from server set boolean loading=true.
This question may be old, but to help others who stumbled upon this problem, i would like to share what i did. I had to implement onScroll Listener to recyclerview to load data from server and to make some UI changes. And also needed swipeRefresh Layout for refreshing data.
This was my xml file structure,
-RelativeLayout
-SwipeRefreshLayout
-NestedScrollView
-LinearLayout(Vertical)
-Multiple views required
After this, to detect up and down scrolling i implemented setOnScrollListener to the NestedScrollView.
Normal usage of SwipeRefreshLayout to refresh data.
And to load more data i implemented the logic inside onScrollListener of NestedScrollingView.
if (scrollY == (v.getChildAt(0).getMeasuredHeight() - v.getMeasuredHeight())) {
// Load More Data
}
If you are recyclerView is embedded in any of the NestedScrollView, then you are supposed to attach the onScrollListener to NestedScrollView.
This will work!
if (recyclerView.getLayoutManager() instanceof GridLayoutManager) {
final GridLayoutManager gridLayoutManager = (GridLayoutManager) recyclerView.getLayoutManager();
nestedScrollView.setOnScrollChangeListener(new NestedScrollView.OnScrollChangeListener() {
#Override
public void onScrollChange(NestedScrollView v, int scrollX, int scrollY, int oldScrollX, int oldScrollY) {
if (scrollY == (v.getChildAt(0).getMeasuredHeight() - v.getMeasuredHeight())) {
totalItemCount = gridLayoutManager.getItemCount();
lastVisibleItem = gridLayoutManager.findLastVisibleItemPosition();
if (!loading
&& totalItemCount <= (lastVisibleItem + visibleThreshold)) {
// End has been reached
// Do something
if (onLoadMoreListener != null) {
onLoadMoreListener.onLoadMore();
}
loading = true;
}
}
}
});
}
You said in a comment to your question "
it is under NestedScrollView which is under coordinator layout, if i remove this, Toolbar is not scrolling up". This is a mistake.
I have found that you cannot have it both ways, the CoordinatorLayout behaviour breaks when you have a RecyclerView inside a NestedScrollView to which you've added the behaviour. You need to use one or the other.
When you have a RecyclerView inside a NestedScrollView it will work as long as you set RecyclerView.setNestedScrollingEnabled(false), but as you found out this means that the OnScrollListener is not called.
The only way for all components to work correctly is to remove the NestedScrollView, make sure you do not set nesting scroll to false and work from there. Otherwise the RecyclerView.OnScrollListener events will not fire correctly.
Step 1 : Create EndlessRecyclerOnScrollListener
public abstract class EndlessRecyclerOnScrollListener extends RecyclerView.OnScrollListener {
public static String TAG = EndlessRecyclerOnScrollListener.class.getSimpleName();
// use your LayoutManager instead
private LinearLayoutManager llm;
public EndlessRecyclerOnScrollListener(LinearLayoutManager sglm) {
this.llm = llm;
}
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
if (!recyclerView.canScrollVertically(1)) {
onScrolledToEnd();
}
}
public abstract void onScrolledToEnd();
}
Step 2: Apply scroll listener to recycler view.
recyclerview.addOnScrollListener(new EndlessRecyclerOnScrollListener(mLayoutManager) {
#Override
public void onScrolledToEnd() {
Log.e("Position", "Last item reached");
if (loadMore == true) {
// put your Load more code
// add 10 by 10 to tempList then notify changing in data
}
}
});
remove the nested scroll view use linear or relative layout instead of it as root element then you can write recyclerview.setNestedScrollEnabled(false);