ramotion/expanding-collection

ExpandingCollection is an iOS animation library written in Swift that lets you build card-based screens where each card can expand to reveal more detail. The visual style follows material design conventions, giving cards a satisfying peek-and-pop motion when a user taps them. Ramotion, a mobile design agency, created and maintains this library as part of a broader set of open-source UI components. The core idea is a horizontally scrolling collection of cards. Each card has a front view and a back view. In its collapsed state only the front is visible, when the user taps, the card animates open to show the back content. You can put whatever views you like inside both sides. A companion transition carries the user forward to a full detail screen, and a matching back transition returns them to the collection. Setting it up requires iOS 9 or later and Xcode 9 or later. You can add it to your project by dropping in the source folder directly, or by using CocoaPods or Carthage, which are standard iOS dependency managers. Once added, you create a custom collection view cell that inherits from the library's base cell class, wire up a front container view and a back container view through the interface builder, then create a view controller that inherits from the library's expanding view controller class. The README includes code samples for registering cells, handling tap events, and triggering the open-close animation. The library is released under the MIT license, meaning you can use it in personal and commercial projects freely. Ramotion also built an Android version of the same concept in Java, linked from the README. A paid iOS showcase app from Ramotion lets you try this component and others in a live environment before integrating them yourself.