The book suggests the app should function (movies should be searchable) after making the changes up to chapter 12 section 4 (using the starter project for chapter 12).
But I had to add the following to SearchMovieActivity for it to work:
private lateinit var searchedMovies: LiveData<List<Movie>>
val movieRepository = MovieRepositoryImpl()
searchedMovies = movieRepository.searchMovies(title)
showLoading()
searchedMovies.observe(this, Observer { it ->
hideLoading()
if (it == null) {
showMessage()
} else {
adapter.setMovies(it)
}
})```