title: Recyclerview adapter/layout that supports a matrix, or multi-dimensional data
body: <p>I've used Recyclerviews with one dimensional data (lists) but that's one dimensional and not what I need. The Grid layout doesn't appear to be quite what I'm looking for as it's used to display a list in a grid like fashion. But the data I'm looking to display is lists that contain lists that contain lists. Essentially, what I want it to look and feel is similar to how Trello does it, however, I'd like all the lanes to move vertically and horizontally in unison, and the lane headers to be fixed at the top at all times. Additionally I'd like groups within the lanes and of course, drag &amp; drop. There's really nothing quite like it out there from what I've seen and almost makes me wonder if the Recyclerview is really even capable of something like that.</p>
  
  <p>My question is, what would be a good approach for something like that? One idea is to not use a Recyclerview at all and just render all the data into a giant scroll view and have the user pan around, but the load time and memory foot print would be kinda horrible (we could have hundreds of items to display). That's the approach we took on a UWP app we made and the results weren't pretty.</p>
  
  <p>Another idea is to make an outer Recyclerview scroll horizontally and each "item" would contain a Recyclerview that scrolls vertically. We'd then need to find a way to scroll all the Recyclerviews vertically when anyone one of them is scrolled, and from what I can tell that's a non-trivial task but it might not be impossible. And we may be able to live with them not scrolling in unison, not sure.</p>
  
  <p>I'm also toying with the idea of making my own layout manager and adapter combo. Not sure if that's all I need or if I also need to extend the Recyclerview. That seems like the most complex approach but it might be the best option in terms of quality.</p>
  
  <p>EDIT: Currently looking into the FixGridLayout from the Recyclerview-Playground project on Github. That has the two-way scrolling but it's still one dimensional data. Getting closer.</p>
  
  <p>Any other ideas?</p>