Dagger2: Unable to inject dependencies in WorkManager

Question

So from what I read, Dagger doesn\'t have support for inject in Worker yet. But there are some workarounds as people suggest. I have tried to do it a number of ways followin

Answer 1

In WorkManager alpha09 there is a new WorkerFactory that you can use to initialize the Worker the way you want to.

• Use the new Worker constructor which takes in an ApplicationContext and WorkerParams.
• Register an implementation of WorkerFactory via Configuration.
• Create a configuration and register the newly created WorkerFactory.
• Initialize WorkManager with this configuration (while removing the ContentProvider which initializes WorkManager on your behalf).

You need to do the following:

public DaggerWorkerFactory implements WorkerFactory {
  @Nullable Worker createWorker(
  @NonNull Context appContext,
  @NonNull String workerClassName,
  @NonNull WorkerParameters workerParameters) {

  try {
      Class workerKlass = Class.forName(workerClassName).asSubclass(Worker.class);
      Constructor constructor = 
      workerKlass.getDeclaredConstructor(Context.class, WorkerParameters.class);

      // This assumes that you are not using the no argument constructor 
      // and using the variant of the constructor that takes in an ApplicationContext
      // and WorkerParameters. Use the new constructor to @Inject dependencies.
      Worker instance = constructor.newInstance(appContext,workerParameters);
      return instance;
    } catch (Throwable exeption) {
      Log.e("DaggerWorkerFactory", "Could not instantiate " + workerClassName, e);
      // exception handling
      return null;
    }
  }
}

// Create a configuration
Configuration configuration = new Configuration.Builder()
  .setWorkerFactory(new DaggerWorkerFactory())
  .build();

// Initialize WorkManager
WorkManager.initialize(context, configuration);