private val loadFeature by lazy { Posts.init() }
private fun injectFeature() = loadFeature

class PostListActivity : AppCompatActivity() {

    private val vm: PostListViewModel by viewModel()

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_post_list)

        injectFeature()

        if (savedInstanceState == null) {
            vm.get(refresh = false)
        }

        vm.posts.observe(this, Observer { updatePosts(it) })
        swipeRefreshLayout.setOnRefreshListener { vm.get(refresh = true) }
    }
}