Add app bar scrolling view behavior to multiple views in CoordinatorLayout

You don’t need a workaround or something strange. This behaviour is supported by the library. Just replace your LinearLayout by this and put it below the RecyclerView:

<android.support.v4.widget.NestedScrollView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:layout_behavior="@string/appbar_scrolling_view_behavior">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:gravity="center">

        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:padding="15dp"
            android:text="Button text"/>

    </LinearLayout>

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

Also you will need to put this in your RecyclerView to show it behind the LinearLayout:

    android:paddingTop="30dp"
    android:clipToPadding="false"

This is how it would look like:

<android.support.design.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">

<android.support.design.widget.AppBarLayout
    android:id="@+id/app_bar_layout"
    android:layout_width="match_parent"
    android:layout_height="@dimen/collapsible_app_bar_height"
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

    <android.support.design.widget.CollapsingToolbarLayout
        android:id="@+id/collapsing_toolbar_layout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@drawable/gradient_banner"
        app:contentScrim="@color/background_content_frame"
        app:layout_scrollFlags="scroll|exitUntilCollapsed">

        <ImageView
            android:id="@+id/image_header"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:src="https://stackoverflow.com/questions/32465548/@drawable/some_image"
            app:layout_collapseMode="parallax"/>

        <android.support.v7.widget.Toolbar
            android:id="@+id/collapsible_toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
            app:layout_collapseMode="pin"/>

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

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

<android.support.v7.widget.RecyclerView
    android:id="@+id/recycler_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_marginTop="@dimen/slide_handle_height"
    android:scrollbars="vertical"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    android:paddingTop="30dp"
    android:clipToPadding="false"/>

<android.support.v4.widget.NestedScrollView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:layout_behavior="@string/appbar_scrolling_view_behavior">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:gravity="center">

        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:padding="15dp"
            android:text="Button text"/>

    </LinearLayout>

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

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

This is not a nice design, but it is a solution. You can put a nicer Layout inside the LinearLayout to make it like Spotify.

Edit: Video added