下面是一个使用Room数据库、RxJava和MVP架构实现Android Recycler Pagination的解决方案的代码示例。
@Entity(tableName = "articles")
public class Article {
@PrimaryKey
public int id;
public String title;
public String content;
}
@Dao
public interface ArticleDao {
@Query("SELECT * FROM articles")
Flowable> getAllArticles();
@Insert(onConflict = OnConflictStrategy.REPLACE)
void insertArticles(List articles);
}
@Database(entities = {Article.class}, version = 1)
public abstract class AppDatabase extends RoomDatabase {
public abstract ArticleDao articleDao();
private static AppDatabase instance;
public static AppDatabase getInstance(Context context) {
if (instance == null) {
instance = Room.databaseBuilder(context.getApplicationContext(), AppDatabase.class, "my_db")
.build();
}
return instance;
}
}
public class ArticlePresenter {
private ArticleView view;
private ArticleDao articleDao;
public ArticlePresenter(ArticleView view, ArticleDao articleDao) {
this.view = view;
this.articleDao = articleDao;
}
public void loadArticles(int page) {
articleDao.getAllArticles()
.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.subscribe(articles -> view.showArticles(articles), throwable -> view.showError(throwable.getMessage()));
}
}
public interface ArticleView {
void showArticles(List articles);
void showError(String error);
}
public class MainActivity extends AppCompatActivity implements ArticleView {
private RecyclerView recyclerView;
private ArticleAdapter articleAdapter;
private ArticlePresenter articlePresenter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
recyclerView = findViewById(R.id.recyclerView);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
articleAdapter = new ArticleAdapter();
recyclerView.setAdapter(articleAdapter);
ArticleDao articleDao = AppDatabase.getInstance(this).articleDao();
articlePresenter = new ArticlePresenter(this, articleDao);
articlePresenter.loadArticles(1);
}
@Override
public void showArticles(List articles) {
articleAdapter.setArticles(articles);
}
@Override
public void showError(String error) {
Toast.makeText(this, "Error: " + error, Toast.LENGTH_SHORT).show();
}
}
public class ArticleAdapter extends RecyclerView.Adapter {
private List articles = new ArrayList<>();
public void setArticles(List articles) {
this.articles = articles;
notifyDataSetChanged();
}
@NonNull
@Override
public ArticleViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_article, parent, false);
return new ArticleViewHolder(view);
}
@Override
public void onBindViewHolder(@NonNull ArticleViewHolder holder, int position) {
Article article = articles.get(position);
holder.titleTextView.setText(article.title);
holder.contentTextView.setText(article.content);
}
@Override
public int getItemCount() {
return articles.size();
}
static class ArticleViewHolder extends RecyclerView.ViewHolder {
TextView titleTextView;
TextView contentTextView;
ArticleViewHolder(View itemView) {
super(itemView);
titleTextView = itemView.findViewById(R.id.titleTextView);
contentTextView = itemView.findViewById(R.id.contentTextView);
}
}
}
这就是一个使用Room数据库、RxJava和MVP架构实现Android Recycler Pagination的解决方案的代码示例。在这个示例中,使用Room数据库来存储和检索数据,使用RxJava来处理异步操作,并使用MVP架构来分离数据逻辑和视图逻辑。