It's pretty straightforward to get started using ExoPlayer by following the library's Hello world! documentation. Once you throw Android's lifecycles and state management into the mix, however, things quickly get more complex. It's easy to accidentally leak memory and hard to coordinate things in a way that's efficient and looks good in the UI. And that's just for playback of videos on a simple screen! Combining ExoPlayer with a ViewPager or RecyclerView adds a whole 'nother layer of complexity.

With this repository I wanted to demonstrate a small app showing how to do Instagram/YouTube Shorts/TikTok style video paging in a way that reconciles Android lifecycles and state management.

The approach I took is to reuse the same ExoPlayer and PlayerView instance for all pages. The ExoPlayer instance lives in and is managed by MainViewModel, and a singular PlayerView gets attached to whichever ViewHolder is active on the current page. Having only one PlayerView makes for a lot less state management.

I've been a bit more verbose with comments than I typically would in this repository, for the purposes of clarity. For testability I've added abstractions that wrap a few ExoPlayer APIs. I've also used an MVI architecture; this increases boilerplate but greatly minimizes state management.

This repository includes examples of streaming videos over the network (from Reddit /r/tiktokcringe) and local assets. It can be modified to handle video data coming from any data source.