RecyclerView shows everything except first item

Maybe your Toolbar hides your first item of your RecyclerView.

Try to use this attribute

android:layout_marginTop="?attr/actionBarSize"

in your RecyclerView xml.

Hope that helps!

There was an app:layout_behavior attribute missing in my layout files.

If anyone else runs into a similar problem, I added app:layout_behavior="@string/appbar_scrolling_view_behavior" to my content layout so that the appbar pushes the content below it instead of overlapping it.