Injection

object Injection : WinterInjection

Abstraction to create, get and dispose a dependency graph from a class that can't make use of constructor injection. This takes the burden off of the class to know how exactly a graph or parent graph is stored and how to create and store a new graph.

An application specific graph creation and retrieval strategy can be provided by setting a custom Adapter.

Injection.adapter = MyCustomAdapter()

To use this abstraction in a library it is recommended to create a library specific object from WinterInjection.

Example using the SimpleAndroidInjectionAdapter which is part of the winter-android module:

class MyApplication : Application() {
  override fun onCreate() {
    super.onCreate()

    // register component
    Winter.component {
      singleton<GitHubApi> { GitHubApiImpl() }

      singleton { RepoListViewModel(instance()) }

      subcomponent("activity") {
         singleton { Glide.with(instance<Activity>()) }
      }
    }

    // register adapter
    Injection.useSimpleAndroidAdapter()
    // create root graph
    Injection.createGraph(this)
  }
}

class MyActivity : Activity() {
  private val injector = Injector()
  private val viewModel: RepoListViewModel by injector.instance()

  override fun onCreate(savedInstanceState: Bundle?) {
    Injection.createGraphAndInject(this, injector)
    super.onCreate(savedInstanceState)
  }

  override fun onDestroy() {
    Injection.disposeGraph(this)
    super.onDestroy()
  }

}

See Also

WinterInjection

Inherited Properties

adapter

var adapter: WinterInjection.Adapter

Set the application specific adapter.

Inherited Functions

createGraph	`fun createGraph(instance: Any, block: ComponentBuilderBlock? = null): Graph` Create and return dependency graph for instance.
createGraphAndInject	`fun createGraphAndInject(instance: Any, injector: Injector, block: ComponentBuilderBlock? = null): Graph` Create and return dependency graph for instance and also pass the graph to the given injector. `fun <T : Any> createGraphAndInject(instance: T, injectSuperClasses: Boolean = false, block: ComponentBuilderBlock? = null): Graph` Create and return dependency graph for instance and inject all members into instance.
disposeGraph	`fun disposeGraph(instance: Any): Unit` Dispose the dependency graph of the given instance.
getGraph	`fun getGraph(instance: Any): Graph` Get dependency graph for instance.
inject	`fun inject(instance: Any, injector: Injector): Unit` Get dependency graph for given instance and inject dependencies into injector. `fun <T : Any> inject(instance: T, injectSuperClasses: Boolean = false): Unit` Inject into instance by using the dependency graph of the instance. This uses MembersInjector and is useful in conjunction with Winters JSR330 annotation processor.

Extension Functions

useApplicationGraphOnlyAdapter

fun WinterInjection.useApplicationGraphOnlyAdapter(tree: WinterTree = GraphRegistry): Unit
fun WinterInjection.useApplicationGraphOnlyAdapter(application: WinterApplication): Unit