title: RecyclerView isn't scrolling
body: <p>I'm making an app, which contains a recyclerView with some items in it. The app uses a BottomNavigationView, and three other fragments to show some content. 
  Now, one of those fragments contains just a RecyclerView and isn't scrolling.</p>
  
  <p>I already tried some things, like changing the height of the RecyclerView from match_parent to wrap_content, wrapping it with a LinearLayout, using a NestedScrollView or regular ScrollView, adding app:layout_behavior and even android:scrollbars. Nothing worked though. </p>
  
  <p>The XML file of the layout with the list which isn't scrolling in it:</p>
  
  <pre><code>&lt;FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:tools="http://schemas.android.com/tools"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:layout_marginBottom="55dp"&gt;
  
      &lt;android.support.v7.widget.RecyclerView
          android:id="@+id/rv_users"
          android:layout_width="match_parent"
          android:layout_height="match_parent"/&gt;
  
  &lt;/FrameLayout&gt;
  </code></pre>
  
  <p>I set the ConstrainedLayout below as the parent of the other Fragment, this also contains the BottomNavigationView (this is generated by Android Studio when I created the project btw):</p>
  
  <pre><code>&lt;android.support.constraint.ConstraintLayout 
  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:id="@+id/main_container"
  android:layout_width="match_parent"
  android:layout_height="match_parent"&gt;
  
      &lt;android.support.design.widget.BottomNavigationView
          android:id="@+id/navigation"
          android:layout_width="0dp"
          android:layout_height="wrap_content"
          android:layout_marginEnd="0dp"
          android:layout_marginStart="0dp"
          android:background="@color/colorPrimary"
          app:itemIconTint="@drawable/bottom_nav_selector"
          app:itemTextColor="@drawable/bottom_nav_selector"
          app:layout_constraintBottom_toBottomOf="parent"
          app:layout_constraintLeft_toLeftOf="parent"
          app:layout_constraintRight_toRightOf="parent"
          app:menu="@menu/navigation" /&gt;
  
  &lt;/android.support.constraint.ConstraintLayout&gt;
  </code></pre>
  
  <p>Finally, this is inside the Fragment's class, where I set the RecyclerView:</p>
  
  <pre><code>    adapter = new UserListAdapter(list, getContext(), getLayoutInflater(), container);
      RecyclerView recyclerView = v.findViewById(R.id.rv_users);
      recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
  
      recyclerView.setAdapter(adapter);
  </code></pre>
  
  <p>I hope one of you guys can help me! </p>