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RecyclerView does not continue to scroll if start scrolling on AppBar in CoordinatorLayout

The application uses a CoordinatorLayout with a CollapsingToolbarLayout. Inside, below it is a RecyclerView with a ScrollingViewBehavior. Everything works correctly (AppBar collapses on scroll), but there is a problem:
If I swipe not the RecyclerView, but the AppBar area (from bottom to top), then the screen will only scroll until the AppBar collapses. For further scrolling, you need to swipe again.
There video for better understand the problem:
gif or video
My layout code:
<androidx.coordinatorlayout.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<com.google.android.material.appbar.AppBarLayout
android:id="#+id/appBarLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar">
<com.google.android.material.appbar.MaterialToolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="400dp"
app:layout_scrollFlags="scroll|enterAlways"
app:title="#string/app_name" />
</com.google.android.material.appbar.AppBarLayout>
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#F5F8FD"
android:orientation="vertical"
android:padding="5dp"
app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>

Android CollapsingToolbarLayout not always collapsing

I have a CoordinatorLayout that I want to use to show a header section on top of a RecyclerView. In the wanted behaviour, both have to be scrolled together:
The idea is to place the header in a CollapsingToolbarLayout with scroll and enterAlwaysCollapsed flags:
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
android:id="#+id/home_appbar"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.design.widget.CollapsingToolbarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_scrollFlags="scroll|enterAlwaysCollapsed"
app:scrimAnimationDuration="0">
<LinearLayout
android:id="#+id/header"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<!-- other header elements -->
</LinearLayout>
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layoutManager="LinearLayoutManager"
tools:listitem="#layout/fragment_option_post"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
/>
</android.support.design.widget.CoordinatorLayout>
However, the header (CollapsingToolbarLayout) not always collapses, allowing the RecyclerView content slide behind it. Sometimes the header collapses too late (for ex. when the firsts recyclerview items are already covered by the header), while other times it behaves as expected.

Scroll stuttering while using coordinator layout with recyclerview

I'm having a problem with Coordinatorlayout and ViewPager implementation.
In order to reproduce this you have to scroll down vigorously and while it's still happening try to scroll the list of items up - a sort of shaky stutter effect can be visible as if CoordinatorLayout was trying to scroll the view in separate direction than its child (RecyclerView).
You can view my layout here:
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/mainContainer"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<android.support.design.widget.AppBarLayout
android:id="#+id/appBarLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.design.widget.CollapsingToolbarLayout
android:id="#+id/collapsingToolbarLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<FrameLayout
android:id="#+id/headerContainer"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</android.support.design.widget.CollapsingToolbarLayout>
<android.support.design.widget.TabLayout
android:id="#+id/tabControl"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:tabIndicatorHeight="4dp"
app:tabMaxWidth="500dp">
</android.support.design.widget.TabLayout>
<LinearLayout
android:id="#+id/topLayout"
android:layout_width="match_parent"
android:layout_height="48dp"
android:orientation="vertical"
android:visibility="gone" />
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/tabContainer"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>
Just to provide some further details:
headerContainer contains ConstraintLayout with some stuff like bunch of textviews, button - pretty usual.
tabContainer contains LinearLayout with list of items (recyclerview)

Add this to the recyclerView in the fragment of your ViewPager..
recyclerView.setNestedScrollingEnabled(false);
This is happening because of the app:layout_behavior="#string/appbar_scrolling_view_behavior" behavior of the viewpager.. this is causing the nestedScrolling.. that is why you feel the shaky effect..

Add this line to your RecyclerView
Recyclerview.setNestedScrollingEnabled(false);

Android AppBarLayout + CollapsingToolbarLayout + CoordinatorLayout

Here is my layout hierarquy
<android.support.design.widget.CoordinatorLayout
android:id="#+id/coordinatorLayout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
android:id="#+id/appBarLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:clipChildren="false"
android:clipToPadding="false"
android:theme="#style/AppThemeAppBarOverlay"
app:elevation="0dp">
<android.support.design.widget.CollapsingToolbarLayout
android:id="#+id/collapsing_toolbar_layout"
contentScrim="#color/transparent"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clipChildren="false"
android:clipToPadding="false"
app:contentScrim="#color/transparent"
app:layout_scrollFlags="scroll|enterAlways">
<LinearLayout
android:id="#+id/openday_parent"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clipChildren="false"
android:clipToPadding="false"
android:orientation="vertical"
android:paddingTop="?attr/actionBarSize"
app:layout_collapseMode="parallax"
app:layout_collapseParallaxMultiplier="1">
...</LinearLayout>
<android.support.v7.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:clipChildren="false"
android:clipToPadding="false"
app:layout_collapseMode="pin"
app:layout_scrollFlags="snap|exitUntilCollapsed"
app:popupTheme="#style/AppThemePopupOverlay" />
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v7.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="#dimen/card_view_margin_bt"
android:background="#color/windowBackground"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:listitem="#layout/card_item" />
</android.support.design.widget.CoordinatorLayout>
<include layout="#layout/navigation_view" />
I have two problems:
When the appbarLayout is expanded, and i perform a quick scroll Up in the recyclerView, the recyclerView scroll really fast and at the same time the collapsing toolbar start collapsing. This shouldnt happen. I want to only allow scroll in the recyclerView when the collapsingLayout is fully collapsed. I think the problem has to do with the recyclerView fling, because if i scroll it slow, this bug doesn't occur. I'm trying to find a workaround for this.
The second thing is, when the activity start, the appbar is expanded. i want it to start collapsed, which works with
appBarLayout.setExpanded(false, true)
But with this approach, the toolbar is also collapsed. I want to just collapse the appBarLayout header but not the toolbar.

The first issue is related to clipToPadding messing with the recyclerView scrolls. Just removed it and the glitch was gone.
The second issue was solved by removing all the toolbar flags and manually translating the view in the appBarLayout listener. Don't know if it is the best thing to do, but worked for me wonderfully.

CoordinatorLayout inside ViewPager inside CoordinatorLayout scrolling issue

I have an outer CoordinatorLayout that has, as AppBar, the Toolbar and a TabLayout bar and, as content, a ViewPager with appbar_scrolling_view_behavior:
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto" android:id="#+id/main_content"
android:layout_width="match_parent" android:layout_height="match_parent"
tools:context=".MainActivity" >
<android.support.design.widget.AppBarLayout android:id="#+id/appbar"
android:layout_width="match_parent" android:layout_height="wrap_content"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar android:id="#+id/toolbar"
android:layout_width="match_parent" android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary" app:popupTheme="#style/AppTheme.PopupOverlay"
app:layout_scrollFlags="scroll|enterAlways|snap">
</android.support.v7.widget.Toolbar>
<android.support.design.widget.TabLayout android:id="#+id/tabs"
android:layout_width="match_parent" android:layout_height="wrap_content"/>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager android:id="#+id/container"
android:layout_width="match_parent" android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
<android.support.design.widget.FloatingActionButton android:id="#+id/fab"
android:layout_width="wrap_content" android:layout_height="wrap_content"
android:layout_gravity="end|bottom" android:layout_margin="#dimen/fab_margin"
android:src="#android:drawable/ic_dialog_email" />
</android.support.design.widget.CoordinatorLayout>
When a tab is selected, the ViewPager is updated with a FrameLayout containing another CoordinatorLayout.
This one should display a collapsable Google Map fragment on top of a RecyclerView (showing a vertical list of items).
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto">
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto" android:id="#+id/nearby_content"
android:layout_width="match_parent" android:layout_height="match_parent"
tools:context=".MainActivity" >
<android.support.design.widget.AppBarLayout
android:id="#+id/app_bar_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true">
<android.support.design.widget.CollapsingToolbarLayout
android:id="#+id/collapsing_toolbar_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
app:contentScrim="?attr/colorPrimary"
app:layout_scrollFlags="scroll|enterAlways">
<fragment
android:id="#+id/mapFragment"
android:name="com.google.android.gms.maps.MapFragment"
android:layout_width="match_parent"
android:layout_height="300dp"
app:layout_collapseMode="parallax" />
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v7.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:behavior_overlapTop="184dp"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>
</FrameLayout>
The expected behavior is that when the user touches inside the map, the map itself should receive the gesture and therefore pan the view.
While if the user scrolls upwards starting the gesture from inside the visible part of the list, the list (RecyclerView) should slide over the collapsing Map, until the AppBar is reached. At that point further scrolling up should slide only the list.
The problem arises when the gesture is not too much slow: part of the scrolling (roughly the equivalent of the TabLayout height) is consumed by the RecyclerView before it reaches the AppBar.
Also, after scrolling all the way up the list, scrolling down first expands the map and then slides the list (leaving the first part of the list hidden), when it should do the viceversa.
Before scrolling up
After scrolling all the way up and down a bit

I'm not very sure about the answer but you can try adding android:nestedScrollingEnabled="false" inside your recycler view:
<android.support.v7.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:behavior_overlapTop="184dp"
android:nestedScrollingEnabled="false"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
Hope it helps.