SwipeRefreshLayout принимает только один дочерний элемент, поэтому, возможно, вы можете иметь ConstraintLayout внутри SwipeRefreshLayout и RecyclerView с кнопками внутри ConstraintLayout.
PS: я предлагаю ConstraintLayout, чтобы избежать вложенных макетов.
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.SwipeRefreshLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/swipe_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior">
<android.support.constraint.ConstraintLayout>
<android.support.v7.widget.RecyclerView
android:id="@+id/students_list"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_marginBottom="8dp"
app:layout_constraintBottom_toTopOf="@+id/selectAllButton"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent"/>
<android.support.v7.widget.AppCompatButton
android:id="@+id/selectAllButton"
android:text="Выбрать всех"
android:layout_weight="1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintBottom_toBottomOf="parent" />
</android.support.constraint.ConstraintLayout>
</android.support.v4.widget.SwipeRefreshLayout>