title: RecyclerView in ConstraintLayout overlapping other elements
body: <p>I'm doing a simple list activity with the following components: an EditText, a RecyclerView, a ProgressBar and a Textview. Everything works really well, except for the RecyclerView which overlaps the EditText and goes "beyond" the screen bottom so the last item is partially cut out (see the screenshots). 
  What an I doing wrong?</p>
  
  <p>MainActivity:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &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:layout_width="match_parent"
      android:layout_height="match_parent"
      tools:context="jacopo.com.flickrgallery.GalleryActivity"&gt;
  
      &lt;EditText
          android:id="@+id/search_text"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:layout_marginEnd="8dp"
          android:layout_marginStart="8dp"
          android:layout_marginTop="8dp"
          android:hint="search by tag..."
          app:layout_constraintEnd_toEndOf="parent"
          app:layout_constraintStart_toStartOf="parent"
          app:layout_constraintTop_toTopOf="parent" /&gt;
  
      &lt;ProgressBar
          android:id="@+id/gallery_progress"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:layout_marginBottom="8dp"
          android:layout_marginEnd="8dp"
          android:layout_marginStart="8dp"
          android:layout_marginTop="8dp"
          app:layout_constraintBottom_toBottomOf="parent"
          app:layout_constraintEnd_toEndOf="parent"
          app:layout_constraintStart_toStartOf="parent"
          app:layout_constraintTop_toBottomOf="@+id/search_text" /&gt;
  
      &lt;android.support.v7.widget.RecyclerView
          android:id="@+id/gallery_list"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:layout_marginBottom="8dp"
          android:layout_marginEnd="8dp"
          android:layout_marginStart="8dp"
          android:layout_marginTop="8dp"
          app:layout_constraintBottom_toBottomOf="parent"
          app:layout_constraintEnd_toEndOf="parent"
          app:layout_constraintStart_toStartOf="parent"
          app:layout_constraintTop_toBottomOf="@+id/search_text" /&gt;
  
      &lt;TextView
          android:id="@+id/gallery_error"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:layout_marginBottom="8dp"
          android:layout_marginEnd="8dp"
          android:layout_marginStart="8dp"
          android:layout_marginTop="8dp"
          app:layout_constraintBottom_toBottomOf="parent"
          app:layout_constraintEnd_toEndOf="parent"
          app:layout_constraintStart_toStartOf="parent"
          app:layout_constraintTop_toBottomOf="@+id/search_text"
          tools:text="error" /&gt;
  
  &lt;/android.support.constraint.ConstraintLayout&gt;
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/RAkv3.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/RAkv3.jpg" alt="recyclerview overlapping editext"></a>
  <a href="https://i.stack.imgur.com/p1fby.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/p1fby.jpg" alt="recyclerView going outside the screen"></a></p>