在上一篇Android 最火的快速开发框架androidannotations配置详解中介绍了在eclipse中配置androidannotation的步骤，如需配置请参考。

1.目标

     androidannotation框架要促进Android应用程序的编写和维护。相信简单的代码有明确的意图是实现这些目标的最佳途径。

   当我们都沉浸在开发Android应用程序时,我们常常会想:为什么我们总是需要反复写相同的代码吗?为什么我们的应用越来越难维护呢？

   context和activity就像是神一样的东西，我们被复杂的线程玩耍，难以参考的API，加载很多的无名监听类，写大量不需要的异常抛出..我们不能改善它们吗？

2.怎么改善

    利用Java 注解机制，开发者能展示他们的意图，还能让androidannotation框架在编译时继承管道代码。

3.特色

*依赖注入：注入view、extras数据、service、resource..

*简单的线程模型：在方法名上注释是在UI线程运行还是后台线程运行

*事件绑定：注释你的方法处理view的事件，不再有难看的匿名监听类。

*REST客户端：创建了一个客户端接口，androidannotation继承了springAndroid的接口。

*不是深不可测：因为AndroidAnnotations继承子类在编译时，你可以检查代码看看它是怎么工作的。

*AndroidAnnotation提供了这么多的好东西甚至它是小于50kb，在运行时没有任何性能影响。

4.使用androidannotation的一些应用

5.对比

Before

public class BookmarksToClipboardActivity extends Activity {
  
  BookmarkAdapter adapter;
 
  ListView bookmarkList;
 
  EditText search;
 
  BookmarkApplication application;
 
  Animation fadeIn;
 
  ClipboardManager clipboardManager;
 
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
 
    requestWindowFeature(Window.FEATURE_NO_TITLE);
    getWindow().setFlags(FLAG_FULLSCREEN, FLAG_FULLSCREEN);
 
    setContentView(R.layout.bookmarks);
 
    bookmarkList = (ListView) findViewById(R.id.bookmarkList);
    search = (EditText) findViewById(R.id.search);
    application = (BookmarkApplication) getApplication();
    fadeIn = AnimationUtils.loadAnimation(this, anim.fade_in);
    clipboardManager = (ClipboardManager) getSystemService(CLIPBOARD_SERVICE);
 
    View updateBookmarksButton1 = findViewById(R.id.updateBookmarksButton1);
    updateBookmarksButton1.setOnClickListener(new OnClickListener() {
 
      @Override
      public void onClick(View v) {
        updateBookmarksClicked();
      }
    });
 
    View updateBookmarksButton2 = findViewById(R.id.updateBookmarksButton2);
    updateBookmarksButton2.setOnClickListener(new OnClickListener() {
 
      @Override
      public void onClick(View v) {
        updateBookmarksClicked();
      }
    });
 
    bookmarkList.setOnItemClickListener(new OnItemClickListener() {
 
      @Override
      public void onItemClick(AdapterView<?> p, View v, int pos, long id) {
        Bookmark selectedBookmark = (Bookmark) p.getAdapter().getItem(pos);
        bookmarkListItemClicked(selectedBookmark);
      }
    });
 
    initBookmarkList();
  }
 
  void initBookmarkList() {
    adapter = new BookmarkAdapter(this);
    bookmarkList.setAdapter(adapter);
  }
 
  void updateBookmarksClicked() {
    UpdateBookmarksTask task = new UpdateBookmarksTask();
 
    task.execute(search.getText().toString(), application.getUserId());
  }
  
  private static final String BOOKMARK_URL = //
  "http://www.bookmarks.com/bookmarks/{userId}?search={search}";
  
  
  class UpdateBookmarksTask extends AsyncTask<String, Void, Bookmarks> {
 
    @Override
    protected Bookmarks doInBackground(String... params) {
      String searchString = params[0];
      String userId = params[1];
 
      RestTemplate client = new RestTemplate();
      HashMap<String, Object> args = new HashMap<String, Object>();
      args.put("search", searchString);
      args.put("userId", userId);
      HttpHeaders httpHeaders = new HttpHeaders();
      HttpEntity<Bookmarks> request = new HttpEntity<Bookmarks>(httpHeaders);
      ResponseEntity<Bookmarks> response = client.exchange( //
          BOOKMARK_URL, HttpMethod.GET, request, Bookmarks.class, args);
      Bookmarks bookmarks = response.getBody();
 
      return bookmarks;
    }
 
    @Override
    protected void onPostExecute(Bookmarks result) {
      adapter.updateBookmarks(result);
      bookmarkList.startAnimation(fadeIn);
    }
    
  }
 
  void bookmarkListItemClicked(Bookmark selectedBookmark) {
    clipboardManager.setText(selectedBookmark.getUrl());
  }
 
}

After

@NoTitle
@Fullscreen
@EActivity(R.layout.bookmarks)
public class BookmarksToClipboardActivity extends Activity {
  
  BookmarkAdapter adapter;
  
  @ViewById
  ListView bookmarkList;
 
  @ViewById
  EditText search;
  
  @App
  BookmarkApplication application;
  
  @RestService
  BookmarkClient restClient;
 
  @AnimationRes
  Animation fadeIn;
  
  @SystemService
  ClipboardManager clipboardManager;
 
  @AfterViews
  void initBookmarkList() {
    adapter = new BookmarkAdapter(this);
    bookmarkList.setAdapter(adapter);
  }
  
  @Click({R.id.updateBookmarksButton1, R.id.updateBookmarksButton2})
  void updateBookmarksClicked() {
    searchAsync(search.getText().toString(), application.getUserId());
  }
  
  @Background
  void searchAsync(String searchString, String userId) {
    Bookmarks bookmarks = restClient.getBookmarks(searchString, userId);
    updateBookmarks(bookmarks);
  }
 
  @UiThread
  void updateBookmarks(Bookmarks bookmarks) {
    adapter.updateBookmarks(bookmarks);
    bookmarkList.startAnimation(fadeIn);
  }
  
  @ItemClick
  void bookmarkListItemClicked(Bookmark selectedBookmark) {
    clipboardManager.setText(selectedBookmark.getUrl());
  }
 
}

@Rest("http://www.bookmarks.com")
public interface BookmarkClient {
  
  @Get("/bookmarks/{userId}?search={search}")
  Bookmarks getBookmarks(String search, String userId);
 
}

<activity android:name=".MyListActivity_" />

跳转activity时也有所不同：

startActivity(this, MyListActivity_.class);

MyListActivity_.intent(context).start();

MyListActivity_.intent(context).startForResult();

MyService_.intent(context).start();

更多的注解使用方法请参考官方文档。

https://github.com/excilys/androidannotations/wiki/Cookbook

如有问题请留言，转载注明出处。