The App Startup library provides a straightforward, performant way to initialize components at application startup. Both library developers and app developers can use App Startup to streamline startup sequences and explicitly set the order of initialization.
Instead of defining separate content providers for each component you need to initialize, App Startup allows you to define component initializers that share a single content provider. This can significantly improve app startup time.
Apps and libraries often rely on having components initialized right away when the app starts up. You can meet this need by using content providers to initialize each dependency, but content providers are expensive to instantiate and can slow down the startup sequence unnecessarily. Additionally, Android initializes content providers in an undetermined order. App Startup provides a more performant way to initialize components at app startup and explicitly define their dependencies.
To use App Startup to initialize components automatically at startup, you must define a component initializer for each component that the app needs to initialize. Implement component initializers
You define each component initializer by creating a class that implements the Initializer interface. This interface defines two important methods:
- The create() method, which contains all of the necessary operations to initialize the component and returns an instance of T.
- The dependencies() method, which returns a list of the other Initializer objects that the initializer depends on. You can use this method to control the order in which the app runs the initializers at startup.