title: ImageView not fading in CollapsingToolbarLayout
body: <p>I am trying to get a fading effect on the ImageView when collapsing the AppbarLayout but the image still remains. I have read other solutions but its not working for me. I cant seem to find what is wrong with the code.</p>
  
  <pre><code>&lt;android.support.design.widget.CoordinatorLayout
  android:id="@+id/coordinatorLayoutProfile"
  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:fitsSystemWindows="true"
  tools:context="com.bolt.citywatch.ui.fragment.ProfileFragment"&gt;
  
  &lt;android.support.design.widget.AppBarLayout
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:fitsSystemWindows="true"
      android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"&gt;
  
      &lt;android.support.design.widget.CollapsingToolbarLayout
          android:layout_width="match_parent"
          android:layout_height="220dp"
          android:background="@color/colorPrimary"
          app:layout_scrollFlags="scroll|exitUntilCollapsed"&gt;
  
  
          &lt;ImageView
              android:id="@+id/profile_image"
              xmlns:app="http://schemas.android.com/apk/res-auto"
              android:layout_width="96dp"
              android:layout_height="96dp"
              android:layout_gravity="center"
              android:src="@drawable/ic_email_white"
              app:layout_collapseMode="parallax"/&gt;
  
  
          &lt;android.support.v7.widget.Toolbar
              android:layout_width="match_parent"
              android:layout_height="?attr/actionBarSize"
              app:layout_collapseMode="pin"
              app:popupTheme="@style/ThemeOverlay.AppCompat.Light"/&gt;
  
      &lt;/android.support.design.widget.CollapsingToolbarLayout&gt;
  
  &lt;/android.support.design.widget.AppBarLayout&gt;
  
  &lt;android.support.v7.widget.RecyclerView
      android:id="@+id/recyclerViewData"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      app:layout_behavior="@string/appbar_scrolling_view_behavior"/&gt;
  </code></pre>
  
  <p></p>