FossifyGallery/app/src/main/res/layout/activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/coordinator_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <android.support.v4.widget.SwipeRefreshLayout
        android:id="@+id/directories_holder"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <android.support.v7.widget.RecyclerView
            android:id="@+id/directories_grid"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:layoutManager="android.support.v7.widget.GridLayoutManager"
            app:spanCount="@integer/directory_columns"/>

    </android.support.v4.widget.SwipeRefreshLayout>
</android.support.design.widget.CoordinatorLayout>