Question

我对设置RecyclerView的适配器有疑问，我在一些教程中看到他们制造了Adapter，然后在与他们设置信息的RecyclerView相同的类中制造。但是我的老师用另一种方式做到这一点，他制作了4个类，即适配器，然后这个类获得名为MovieServices的所有信息：

public class MoviesService
{
public static MoviesService moviesService;

public static MoviesService getInstance()
{
    if ( moviesService == null )
    {
        moviesService = new MoviesService();
    }

    return moviesService;
}

private List<Movie> movies;

private MoviesService()
{
    this.movies = new ArrayList<>();

    movies.add( new Movie("001", "El hombre que mató a Liberty Valance", 9.8) );
    movies.add( new Movie("002", "Río Rojo", 9.2) );
    movies.add( new Movie("003", "Río Bravo", 9.9) );
    movies.add( new Movie("004", "La diligencia", 9.1) );
    movies.add( new Movie("005", "Que verde era mi valle", 9.8) );
    movies.add( new Movie("006", "El hombre tranquilo", 9.3) );
    movies.add( new Movie("007", "Misión de audaces", 9) );
    movies.add( new Movie("008", "La taberna del irlandés", 8.6) );
    movies.add( new Movie("009", "El Padrino", 9.5) );
    movies.add( new Movie("010", "El Padrino II", 9.6) );
    movies.add( new Movie("011", "El Padrino III", 9.7) );
    movies.add( new Movie("012", "Los increibles", 9.2) );
    movies.add( new Movie("013", "Los increibles II", 8.9) );
    movies.add( new Movie("014", "Coco", 9.6) );
}

public List<Movie> getMovies()
{
    return movies;
}

public Movie getMovie(int position)
{
    return movies.get( position );
}


public void update(int moviePosition, Movie movie)
{
    movies.set(moviePosition, movie);
}
}

然后他又叫另一个班级

public class MainViewModel extends ViewModel
{
private MoviesService moviesService;


public MainViewModel()
{
    moviesService = MoviesService.getInstance();
}

public List<Movie> getMovies()
{
    return moviesService.getMovies();
}

public Movie getMovie(int position)
{
    return moviesService.getMovie( position );
}
}

最后是具有RecyclerView的类：

public class MainActivity extends AppCompatActivity implements MovieAdapter.OnItemClickListener
{

private MainViewModel viewModel;
private RecyclerView rv;
private RecyclerView.LayoutManager layoutManager;
private MovieAdapter adapter;


@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    this.viewModel = ViewModelProviders.of(this).get(MainViewModel.class);
    this.rv = findViewById(R.id.rv);
    this.layoutManager = new LinearLayoutManager(this, RecyclerView.VERTICAL, false);
    this.adapter = new MovieAdapter(this);
    this.adapter.setOnItemClickListener(this);

    rv.setAdapter( adapter );
    rv.setLayoutManager( layoutManager );
    adapter.setMovies( viewModel.getMovies() );
}

@Override
public void onItemClick(View view, int position) {

    Movie movie = this.viewModel.getMovie(position);
    Toast.makeText(this, movie.getName(), Toast.LENGTH_SHORT).show();

    Intent intent = new Intent(this, MovieActivity.class );
    intent.putExtra(MovieActivity.EXTRA_MOVIE_POSITION, position);
    startActivityForResult( intent, 88 );
}

@Override
protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
    switch ( requestCode )
    {
        case 88:  if ( resultCode == Activity.RESULT_OK)
                  {
                      adapter.setMovies( viewModel.getMovies() );
                  }
                  break;
    }
}
}

但是我不确定哪种方式会更优化，因为我认为他做了很多我认为不必要的事情。谢谢！

Answer 1

最好的方法是按照以下步骤创建单独的元素，以进行清晰的编码：

1-创建一个单独的自定义对象类

2-创建一个单独的RecyclerView.Adapter，将数据填充到RecyclerView

3-在单独的活动中将适配器绑定到RecyclerView

哪种形式的RecyclerView适配器更好？

1 个答案: