Open Source Java Build Tools for Android

Dagger is a fully static, compile-time dependency injection framework for Java, Kotlin, and Android. It is an adaptation of an earlier version created by Square and now maintained by Google. The latest Dagger release is: Dagger 2.33. Dagger aims to address many of the development and performance issues that have plagued reflection-based solutions. Dagger is a replacement for the FactoryFactory classes that implements the dependency injection design pattern without the burden of writing the boilerplate. It allows you to focus on the interesting classes. Declare dependencies, specify how to satisfy them, and ship your app. Dependency injection frameworks have existed for years with a whole variety of APIs for configuring and injecting. So, why reinvent the wheel? Dagger 2 is the first to implement the full stack with generated code. The guiding principle is to generate code that mimics the code that a user might have hand-written to ensure that dependency injection is simple.

Litho uses a declarative API to define UI components. You simply describe the layout for your UI based on a set of immutable inputs and the framework takes care of the rest. With code generation, Litho can perform optimisations for your UI under the hood, while keeping your code simple and easy to maintain. Litho can measure and layout your UI ahead of time without blocking the UI thread. By decoupling its layout system from the traditional Android View system, Litho can drop the UI thread constraint imposed by Android. Litho uses Yoga for layout and automatically reduces the number of ViewGroups that your UI contains. This, in addition to Litho's text optimizations, allows for much smaller view hierarchies and improves both memory and scroll performance.