I would like to switch the recycler view layout while loading so there will be displayed something indicating the progress:
There is nothing I know of that's built into RecyclerView to handle this. You'll have to implement your own loading behavior
In the same view that owns your RecyclerView you should add a ProgressBar, when you make your call to fetch the data for your RecyclerView hide the RecyclerView and show the ProgressBar. Switch them back once your data is loaded
<FrameLayout
android:layout_height="match_parent"
android:layout_width="match_parent">
<!-- Your RecyclerView here -->
<ProgressBar
android:id="@+/progress_bar"
android:layout_height="match_parent"
android:layout_width="match_parent"
android:indeterminate="true"/>
</FrameLayout>