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RecyclerView as child of NestedScrollView - not recycling views

I am trying to create a scroll-able area which will contain various sections of the following types:
Horizontal Recycling Section
Vertical Recycling Section
Text Section
The approach I am taking is to have a NestedRecyclerView as the parent scroll view for all the child sections. This view looks like so:
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<androidx.coordinatorlayout.widget.CoordinatorLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<com.google.android.material.appbar.AppBarLayout
android:id="#+id/mynav_appbarLayout"
android:background="?attr/themeToolbarBg"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<include
android:id="#+id/mynav_toolbar"
layout="#layout/actionbar_toolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</com.google.android.material.appbar.AppBarLayout>
<androidx.core.widget.NestedScrollView
android:id="#+id/nestedScrollView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fillViewport="true"
app:layout_behavior="com.google.android.material.appbar.AppBarLayout$ScrollingViewBehavior">
<LinearLayout
android:id="#+id/content"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"/>
</androidx.core.widget.NestedScrollView>
</androidx.coordinatorlayout.widget.CoordinatorLayout>
</layout>
Then, for each section type I am creating a corresponding view binding and adding it as a child to the LinearLayout which is inside the NestedScrollView.
There are 2 types of section layout, one which is a simple TextView (which I will omit here as it is not relevant) the other of which is a view which contains a RecyclerView. The layout manager for this RecyclerView is created dynamically depending on whether the section it is to be used for is a horizontal or vertical section.
The layout with the RecyclerView in looks like so:
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<LinearLayout
android:id="#+id/content"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:focusable="true"
android:focusableInTouchMode="true">
<TextView
android:id="#+id/title"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="24dp"
android:layout_marginTop="8dp"/>
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/fooBarsRecycler"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginStart="16dp"
android:layout_marginTop="8dp"
android:nestedScrollingEnabled="false"
app:layout_behavior="com.google.android.material.appbar.AppBarLayout$ScrollingViewBehavior"/>
</LinearLayout>
</layout>
Now, when I am adding these views to the parent NestedScrollView's LinearLayout and setting up the LayoutManager for the associated RecyclerView to orientation Horizontal it works fine, but, when I use orientation Vertical (which is the same orientation as the NestedScrollView) the RecyclerView is NOT recycling views. Obviously this is leading to unacceptable performance.
After doing about a days worth of research and banging my head against the wall it appears that having a RecyclerView nested within a NestedScrollView with the same orientation as the NestedScrollView causes the RecyclerView to lose it's recycler functionality.
As you can hopefully see from the above layout, I have tried all the suggestions I could find, making sure the RecyclerView's height is not wrap_content, using layout_behaviour, setting the NestedRecyclerView to fill view port and so on.
I have exhausted 6 pages of google search around this issue and have tried every suggestion I have found either on SO or blogs and nothing is working.
Oddly, if I swap out the NestedScrollView for a ScrollView, the vertical RecyclerView regains it's recycler functionality, but now scrolls independently of the parent ScrollView which doesn't meet our requirements.
Is this a solved problem or do I need to rethink my entire solution? I.e. am I just missing an attribute or doing something wrong in the XML or is it fundamentally an issue with using a RecyclerView inside a NestedScrollView with the same orientation?
Here is the list of resources, the suggestions of which I have tried exhaustively to no avail:
How to use RecyclerView inside NestedScrollView?
How to use RecyclerView inside NestedScrollView
Recycler view inside NestedScrollView causes scroll to start in the middle
https://android.jlelse.eu/recyclerview-within-nestedscrollview-scrolling-issue-3180b5ad2542
https://medium.com/#mujtahidah/load-more-recyclerview-inside-nested-scroll-view-and-coordinator-layout-4f179dc01fd
https://github.com/google/flexbox-layout/issues/400
https://www.reddit.com/r/androiddev/comments/8oj8cb/having_recyclerview_inside_a_nestedscrollview_is/
https://github.com/mikepenz/FastAdapter/issues/447
https://www.reddit.com/r/androiddev/comments/bixl6r/nestedscrollview_recyclerview/
View Recycling not happens with Multiple Recyclerview inside NestedScrollView
How to make RecyclerView do recycling inside NestedScrollView?
https://code-examples.net/en/q/1d90611
As per a suggestion in the comments, I could model this with a multi type adapter, which is something I have done before but for this particular problem I am not sure this approach will work.
I think the comment is suggesting I model it like so:
Where the adapter would adapt types:
Horizontal Section
Text Section
Card Section
But, the requirement is this:
So, as you can hopefully see, the RecyclerView will have a LinearLayoutManager with orientation Vertical, but, once we hit the cards, they have to be laid out in a grid fashion, which of course the LinearLayoutManager does not support. So, perhaps I can have the final section be another RecyclerView with a GridLayoutManager? But, I tried this last night and it didn't work, there were scrolling issues as the bottom most RecyclerView is scrolling vertically within the outermost RecyclerView which is also scrolling vertically.

BottomSheet: issue with nested scrolling (RecyclerView & NestedScrollView)

I have a rather complex BottomSheetLayout which layout is as follow
The root view of my bottom sheet is a custom FrameLayout that allows to round it's corner (both background and children). Nothing else (nothing touch-related)
Then, I use the usual ConstraintLayout in order to layout my Bottom sheet.
This ConstraintLayout contains, amongst other views, a vertical RecyclerView:
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="10dp">
<!-- other views -->
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/events"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginTop="25dp"
android:layout_marginBottom="74dp"
app:layout_constraintTop_toBottomOf="#+id/days"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
android:background="#{viewModel.colors.defaultBackgroundColor}"
tools:background="#ECF0F3"
android:orientation="vertical"
app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
tools:listitem="#layout/event_item"
tools:itemCount="10" />
</androidx.constraintlayout.widget.ConstraintLayout>
I have no particular issue while dragging my bottom sheet, however, when fully expanded I was expecting the be able to scroll the content of my RecyclerView. But I cannot.
After a lot of researches, I managed to make it scroll by enabling scrolling when my Fragment's view is inflated :
ViewCompat.setNestedScrollingEnabled(this.binding.bottomSheetEvents.getRoot(), true);
However, doing so has a weird consequence. When my bottom sheet's state is EXPANDED, I can finally scroll my RecyclerView, but then there is absolutely no way to drag my Bottom sheet any more : it remains fully expanded.
I have tried a few other ways.
I have tried wrapping my NestedScrollView. In past experience I was able to have the full content of my bottom sheet scrollable thanks to NestedScrollView, but in this case, I only want to scroll my RecyclerView. What ever is above it must remain idle.
I have tired this.binding.bottomSheetEvents.events.setNestedScrollingEnabled(false); but there is no difference.
My belief is that when the bottom sheet is fully expanded, it dispatches scroll events to inner children that can supports its. And, backwards, it knows, at some point, when uses wishes to collapse said bottom sheet. So I guess, something wrong must be happening there.
Further informations:
this bottomsheet is included in my fragment which roots view is a CoordinatorLayout obviously.
the fragment is also hosted in CoordinatorLayout with an AppBar
the include layout uses the app:layout_behavior="#string/bottom_sheet_behavior"
and the include layout also uses behavior_fitToContents set to false so that I can use method setExpandedOffset to prevent the bottom sheet to reach the top.
Version used : 1.1.0-alpha07
Thanks for the help!

RecyclerView inside NestedScrollview not scrolling smoothly

When I'm scrolling down, the items above the RecyclerView does not scroll unless I start touching from the layout above, and it only scrolls down when I have reached the end of the RecyclerView.
<NestedScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout>
<Some other items.../>
</LinearLayout>
<RecyclerView
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</NestedScrollView>
Note:
I actually use a fixed size for the RecyclerView, setting it via the code below:
float height_recyclerview = (ScreenUtil.getHeight(context) - (height_banner + height_bottom_navigation + height_create_post));
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, (int) height_recyclerview);
rv.setLayoutParams(layoutParams);
Why do I use fixed size if it works smoothly with wrap_content?
I will be displaying possibly thousands of items that may have
images, which will hurt performance if it does not actually do
recycling because of the issue that the RecyclerView is inside the
NestedScrollView
I have implemented an EndlessRecyclerViewScrollListener which has an
issue that it keeps loading more data from server continuously if
implemented with a RecyclerView that is within whatever scrollable
view, or if it is in a scrollable view, but does not have a fixed
height, even if you are not scrolling down.
I have tried the following:
set nested scrolling to false on the recycler view
try using scroll view instead of nested scroll view
a bunch of other code related to layouts and scrolling behaviors that others suggested which didn't work for me because I'm implementing it in a much more complicated layout and the fact that I use EndlessRecyclerViewScrollListener
What I want to fix?
I want to make the page scroll like a single page, not as a separate scrollable view.
Note that my recycler view has a fixed height that takes the entire screen's space meaning that its height is actually fit assuming that the linear layout above is not visible anymore if the user has scrolled down.
The ideal scenario is to make the scrollview scroll down first, to make the recycler view take the entire screen, so that the recyclerview will scroll however the user wants to.
Then the linearlayout above which should not be visible anymore if the recycler view has taken up all the space of the screen, should only show up if the recycler view has reached the top/first item, if the user keeps scrolling back up.

Read this.
Add app:layout_behavior="#string/appbar_scrolling_view_behavior" to your recycler xml.
<android.support.v7.widget.RecyclerView
android:id="#+id/conversation"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
android:layout_width="match_parent"
android:layout_height="wrap_content" />

NestedScrollView Smooth Scrolling
recyclerView.isNestedScrollingEnabled = true
Do this programmatically
<androidx.core.widget.NestedScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="0dp"
android:fillViewport="true"
...

Lazy-load views in RecyclerView within NestedScrollView

Targeting androidx 1.0.0 to allow for pre-Lollipop devices (let's say minSdkVersion 17 or so).
I have tried many combinations of views, settings, scrolling modes and layout managers. I have read everything - e.g. this and this and this - regarding this problem. Either I get bad layout/rendering performance or incorrect/buggy scrolling.
Requirements:
A bottomsheet is draggable from the bottom. A common UI pattern in modern apps.
10-20 heavy equally sized child views. These must not be inflated/drawn when invisible.
Using native Android/Google views is preferable.
How can I achieve this?
Here's some pseudo code, showing what I'm trying to accomplish; a RecyclerView (or equivalent) inside a NestedScrollView with a BottomSheetBehavior:
<ScrollView>
<!-- Main content -->
</ScrollView>
<androidx.core.widget.NestedScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fillViewport="true"
android:fitsSystemWindows="true"
app:layout_behavior="com.google.android.material.bottomsheet.BottomSheetBehavior"
app:behavior_hideable="false"
app:behavior_peekHeight="#dimen/bottom_sheet_peek_height">
<!-- RecyclerView? -->
<TextView android:layout_width="match_parent"
android:layout_height="#dimen/bottom_sheet_peek_height"
android:text="Bottom sheet header" />
<-- N heavy equally sized child views here -->
</androidx.core.widget.NestedScrollView>
I have read that RecyclerView outperforms ListView. Still, it seems to never recycle its views given the above configuration.

NestedScrollView (NSV) in CoordinatorLayout (CL): NSV Not at Top When Loaded

I am using an NSV in a CL for the ability to have the toolbar compress when the NSV scrolls down. The problem that I am having is that my NSV is not scrolled to the top when it loads, instead, it is offset from the top of the NSV by quite a margin (I am not certain where this spacing is coming from, it's not in the layout).
Please take a look at the screen captures, the first one shows how the NSV loads and you can clearly see the NSV has scrolled down quite a bit from the top by comparing the second (when I scroll the NSV to the top manually):
I did some updates to this layout and it caused this to occur, previously, it loaded at the top without issue. However, I did not add any spacing that should have caused this.
Here is the layout I'm using for this:
<android.support.design.widget.CoordinatorLayout
android:id="#+id/cl_goal_detail"
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1">
<android.support.design.widget.AppBarLayout
android:id="#+id/abl_goal_detail"
android:layout_width="match_parent"
android:layout_height="144dp"
app:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.design.widget.CollapsingToolbarLayout
android:id="#+id/collapsing_toolbar_goal_detail"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/content_space_double"
app:collapsedTitleTextAppearance="#style/title.dark"
app:expandedTitleTextAppearance="#style/display3.plus.dark"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar_goal_detail"
style="#style/toolbar"
app:layout_collapseMode="pin"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light"/>
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v4.widget.NestedScrollView
android:id="#+id/nsv_goal_detail"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/content_space_half"
android:paddingLeft="#dimen/content_space_half"
android:paddingRight="#dimen/content_space_half"
app:layout_behavior="#string/appbar_scrolling_view_behavior">
<FrameLayout
android:id="#+id/container_goal_detail"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="fill_vertical"/>
</android.support.v4.widget.NestedScrollView>
</android.support.design.widget.CoordinatorLayout>
Any ideas would be appreciated!

OK! After a solid DAY of debugging every single component of my layout and Fragment I identified what I believe is a bug.
First, the issue: Turns out that having elements in your NSV's child view that change visibility to View.GONE upon runtime are causing the list to scroll down. I noticed that the list scrolls to just above the element where the visibility was toggled (including any margins set on the view).
Second, the fix: I fixed this issue by setting all the views to have android:visibility="gone" in the xml layout, then, I toggle each view's visibility as needed. Previously, the views were visible by default and then I worked from there. I just needed to change my logic to start with them all GONE, not terribly difficult.
I assume this works because the views you are going to hide at runtime do not form a part of the overall height calculation when the NSV is created in onCreateView(). Once the fragment progresses past onCreateView() it's safe to dynamically change the views, however, if the views are calculated as part as the height in onCreateView() and THEN hidden with View.GONE, measurements go wonky and you end up with a list scrolled down significantly.

Have you tried adding below line in your viewgroup i.e. FrameLayout in your case
android:descendantFocusability="blocksDescendants"
I think this will also work for you.
If not try it adding in NSV.

In my case, there was an EditText near the bottom of my scrolling content that was grabbing focus. Since NestedScrollView does some weird layout stuff, the focused view didn't scroll to the top when the activity started, so the real cause was not readily apparent. Adding this to the NestedScrollView's child layout fixed it for me:
android:focusableInTouchMode="true"

Your post answer helped me a lot to find out my issue (btw, it was the same). But I got it worked in a different way. I guess you are using a RecyclerView. In my case I'm using 3 RecyclerViews. Well, from your answer I started hiding the recyclers and I found out just one of them was causing this issue. What I did is I populated with a postDelayed:
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
recyler.setLayoutManager(new LinearLayoutManager(getApplicationContext()));
recyler.setAdapter(new MyAdapter(myList));
}
}, 3000);
That worked fine!