It took me 8 hours to solve this problem. I was creating a custom view that extends LinearLayout and having a RecyclerView as child. The problem was that RecyclerView didn't measured correctly so the width and height stayed on 0dp. The RecyclerView was never visible.
While trying some tricks and hacks to measure the RecyclerView, I've found out that this was just an Android bug that's fixed on februari 25, 2016. RecyclerView was ignoring the layout params such as WRAP_CONTENT and MATCH_PARENT.
Upgrade the RecyclerView dependency at least to this version:
Also take a look at this article about Android Support Library 23.2.
Happy programming all!