I am getting familiar with the new support.design library and I'm facing this issue with the FloatingActionButton. I'm trying to hide it programmatically, but the button stay always visible.
I have the feeling that app:layout_anchor="@id/appbar" must override the visibility of the button.
JAVA:
@InjectView(R.id.search_fab)
FloatingActionButton search_fab;
[...]
search_fab.setVisibility(View.GONE);
XML:
<android.support.design.widget.AppBarLayout
    android:id="@+id/appbar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:fitsSystemWindows="true">
    <android.support.design.widget.CollapsingToolbarLayout
        android:id="@+id/collapsing_toolbar"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_scrollFlags="scroll|exitUntilCollapsed"
        android:fitsSystemWindows="true"
        app:contentScrim="?attr/colorPrimary"
        app:expandedTitleMarginStart="48dp"
        app:expandedTitleMarginEnd="64dp"
        android:theme="@style/ToolBarStyle"
        >
        <android.support.v7.widget.RecyclerView
            android:layout_width="match_parent"
            android:layout_gravity="center"
            android:layout_height="210dp"
            android:id="@+id/top_sales_product_recycler_view"
            />
        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
            app:layout_collapseMode="pin"
            android:theme="@style/ToolBarStyle"
            />
    </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"
    android:id="@+id/category_recycler_view"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    />
<android.support.design.widget.FloatingActionButton
    android:layout_height="wrap_content"
    android:layout_width="wrap_content"
    app:layout_anchor="@id/appbar"
    app:layout_anchorGravity="bottom|right|end"
    android:src="@drawable/abc_ic_search_api_mtrl_alpha"
    android:layout_margin="@dimen/fab_margin"
    android:id="@+id/search_fab"
    app:borderWidth="1dp"
    />
				
                        
To get rid of the anchor you can use:
As far as I know, having an anchor does really, as you say, affect the possibility of hiding the button, so calling this before the visibility change should work.