IssueTracker

Library used (support-v4, appcompat-v7, ...):support-v4, appcompat-v7, design, cardview-v7, recyclerview-v7, customtabs
Version used: 26.0.2
Theme used: Theme.AppCompat.NoActionBar
Devices/Android versions reproduced on: AVD API 25

I just upgraded to API 26 and support library 26.0.2. But I found that my RecyclerView items is not clickable right after the scrolling. If you wait for a second, it will work. But if you click the item immediately, it won't. Even if the RecyclerView is not scrolling at all(e.g. has scrolled to the top).

When I downgraded to support library 25.4.0 everything goes fine again. The key point is that my RecyclerView is in a CoordinatorLayout and has a SCROLL_FLAG_SCROLL flag on my Toolbar of the AppBarLayout. If I don't use this flag, then this problem will disappear.

I've tried to add focusable="false" to the CoordinatorLayout but still had no luck.
Is there any way to disable this behavior? Because it's really annoying to click twice to trigger the click event.

I think the problem is the scrollState of the RecyclerView. When it's stopped scrolling, it's not changed to SCROLL_STATE_IDLE immediately. Looking into the source code of RecyclerView, I found there's a ViewFlinger controlling the scroll state. When I fling down to scroll to the top, it's not calling setScrollState(SCROLL_STATE_IDLE) immediately. Instead, it wait for a while to trigger this method. The more fast I fling, the more time I need to wait. It just like the RecyclerView is still scrolling in the background. Because the scroller.isFinished() doesn't return true right after the RecyclerView stop scrolling when it touched the top. Maybe it's a bug of the RecyclerView when it's in a CoordinatorLayout.

The attachment is a screen recording of this behavior.

<android.support.design.widget.CoordinatorLayout
        android:id="@+id/coordinateLayout"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

    <android.support.design.widget.AppBarLayout
            android:id="@+id/fragmentAppBar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:elevation="0dp"
            android:background="@null">
        <include
                android:id="@+id/dynamicActionBarHolder"
                layout="@layout/dynamic_action_bar"/>
    </android.support.design.widget.AppBarLayout>

    <android.support.v4.widget.SwipeRefreshLayout
            android:id="@+id/pullToRefreshMailRecycler"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_behavior="@string/appbar_scrolling_view_behavior">

        <android.support.v7.widget.RecyclerView
                android:id="@+id/mailRecyclerView"
                android:layout_width="match_parent"
                android:layout_height="match_parent"/>

    </android.support.v4.widget.SwipeRefreshLayout>

</android.support.design.widget.CoordinatorLayout>


layout/dynamic_action_bar.xml

<FrameLayout 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="?attr/actionBarSize"
                app:layout_scrollFlags="scroll"
                android:clickable="true"
                android:background="?theme.dynamicActionBarBackground">

    <ImageButton
            android:id="@+id/dynamicAcbMenuIcon"
            android:layout_width="?attr/actionBarSize"
            android:layout_height="?attr/actionBarSize"
            android:background="@drawable/article_explicit_button_background"
            android:src="?theme.menuIcon"/>

    <RelativeLayout
            android:id="@+id/dynamicAcbTitleHolder"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginStart="?attr/actionBarSize"
            android:paddingTop="5dp"
            android:paddingBottom="5dp"
            android:paddingEnd="5dp"
            android:layout_gravity="center_vertical">

        <TextView
                android:id="@+id/dynamicAcbTitle"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:singleLine="true"
                android:textSize="@dimen/action_bar_title_portrait_size"
                android:textColor="?theme.listItemTitleColor"
                android:ellipsize="end"
                android:text="ActionBar"/>

        <TextView
                android:id="@+id/dynamicAcbSubtitle"
                android:layout_below="@+id/dynamicAcbTitle"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:singleLine="true"
                android:textSize="@dimen/action_bar_subtitle_portrait_size"
                android:textColor="?theme.listItemTitleColor"
                android:ellipsize="end"
                android:text="If you say so"/>

    </RelativeLayout>

</FrameLayout>