title: android toolbar becomes unreachable with AppBarLayout$ScrollingViewBehavior
body: <p>my current application has a custom backdrop that contains user options that control the front layer content.</p>
  <p>the majority of the front layer screens contain recyclerviews and my toolbar scrolls using</p>
  <pre><code>&lt;androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot;
      xmlns:app=&quot;http://schemas.android.com/apk/res-auto&quot;
      xmlns:tools=&quot;http://schemas.android.com/tools&quot;
      android:id=&quot;@+id/backdrop_activity_anchor_view&quot;
      android:layout_width=&quot;match_parent&quot;
      android:layout_height=&quot;match_parent&quot;
      android:background=&quot;@android:color/transparent&quot;
      android:keepScreenOn=&quot;true&quot;
      app:layout_behavior=&quot;android.support.design.widget.AppBarLayout$ScrollingViewBehavior&quot;
      tools:context=&quot;.MyActivity&quot;&gt;
  </code></pre>
  <p>and this</p>
  <pre><code>&lt;?xml version=&quot;1.0&quot; encoding=&quot;utf-8&quot;?&gt;
  &lt;com.google.android.material.appbar.AppBarLayout xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot;
      xmlns:app=&quot;http://schemas.android.com/apk/res-auto&quot;
      android:id=&quot;@+id/toolbarLayout&quot;
      android:layout_width=&quot;match_parent&quot;
      android:layout_height=&quot;wrap_content&quot;&gt;
  
      &lt;androidx.appcompat.widget.Toolbar
          android:id=&quot;@+id/toolbar&quot;
          android:layout_width=&quot;match_parent&quot;
          android:layout_height=&quot;?attr/actionBarSize&quot;
          android:elevation=&quot;@dimen/toolbar_elevation&quot;
          android:theme=&quot;@style/ToolbarTheme&quot;
          android:title=&quot;@string/app_name&quot;
          android:background=&quot;@color/tool_bar&quot;
          app:layout_scrollFlags=&quot;scroll|enterAlways&quot;
          app:subtitleTextColor=&quot;#BBFFFFFF&quot;
          app:titleTextColor=&quot;@color/white&quot;&gt;
  
          &lt;View
              android:id=&quot;@+id/paddingView&quot;
              style=&quot;?android:attr/progressBarStyle&quot;
              android:layout_width=&quot;@dimen/menu_progressbar_size&quot;
              android:layout_height=&quot;@dimen/menu_progressbar_size&quot;
              android:layout_gravity=&quot;end&quot; /&gt;
  
          &lt;ProgressBar
              android:id=&quot;@+id/loadingProgress&quot;
              style=&quot;?android:attr/progressBarStyle&quot;
              android:layout_width=&quot;@dimen/menu_progressbar_size&quot;
              android:layout_height=&quot;@dimen/menu_progressbar_size&quot;
              android:layout_gravity=&quot;end&quot;
              android:indeterminateTint=&quot;#FFFFFF&quot;
              android:visibility=&quot;invisible&quot; /&gt;
  
      &lt;/androidx.appcompat.widget.Toolbar&gt;
  
  &lt;/com.google.android.material.appbar.AppBarLayout&gt;
  </code></pre>
  <p>i have an issue under the following conditions</p>
  <p>the user opens the backdrop and selects a scrolling screen.
  they scroll to the bottom of the list and in doing so the toolbar disappears
  now they select a non scrolling screen</p>
  <p>this navigation now means the user cannot see the toolbar and can only re access it by either changing device orientation or selecting a scrolling screen from the backdrop</p>
  <p>is there any approach i can take that programmatically displays the toolbar on my non scrolling front layer screens?</p>
  <p>or</p>
  <p>is there a <code>layout_behavior</code> or <code>layout_scrollFlags</code> value(s) that would resolve my issue</p>