示例代码

@ViewId(R.id.button)
private Button button;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
     setContentView(R.layout.activity_main);
    ViewUtils.inject(this);
    button.setText( "123" );
}

@OnClick({R.id.button})
private void aaaaaaa( View view ) {
    Toast.makeText( this, "tttttttt", Toast.LENGTH_SHORT).show();
}

@OnClick(R.id.imageView)
private void ttttttt() {
    Toast.makeText( this, "ddddddddddd", Toast.LENGTH_SHORT).show();
}

ViewUtils

public class ViewUtils {

public static void inject(Activity activity) {
    inject(new ViewFinder(activity), activity);
}

public static void inject(View view) {
    inject(new ViewFinder(view), view);
}

public static void inject(View view, Object object) {
    inject(new ViewFinder(view), object);
}

public static void inject( ViewFinder viewFinder, Object object ) {
    injectFiled(viewFinder,object);
    injectEvent(viewFinder,object);
}

private static void injectFiled(ViewFinder viewFinder, Object object) {
    Class<?> clazz = object.getClass();
    // 所有变量
    Field[] fields = clazz.getDeclaredFields();
    for (Field field : fields) {
        // 注解类型
        ViewId viewById = field.getAnnotation(ViewId.class);
        // 注解不存在
        if( viewById == null ) continue;
        // 注解的值，ViewID
        int viewId = viewById.value();
        // 查找，获取View
        View view = viewFinder.findViewById(viewId);
        if( view == null ) continue;
        try {
            //  能够注入所有修饰符
            field.setAccessible( true );
            field.set(object,view);
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }
    }
}

private static void injectEvent(ViewFinder viewFinder, Object object) {
    Class<?> clazz = object.getClass();
    // 所有变量
    Method[] methods = clazz.getDeclaredMethods();
    for (Method method : methods) {
        OnClick onClick = method.getAnnotation(OnClick.class);
        if( onClick == null ) continue;
        int[] value = onClick.value();
        if( value.length == 0 ) continue;
        for (int viewId : value) {
            View view = viewFinder.findViewById(viewId);
            if( view == null ) continue;
            view.setOnClickListener( new DeclaredOnClickListener( view, object , method) );
        }
    }
}

private static class DeclaredOnClickListener implements View.OnClickListener {

    private View clickView;
    private Object clickObject;
    private Method clickMethod;

    public DeclaredOnClickListener( View view, Object object, Method method ) {
        this.clickView = view;
        this.clickObject = object;
        this.clickMethod = method;
    }

    @Override
    public void onClick(View v) {
        try {
            clickMethod.setAccessible(true);
            clickMethod.invoke( clickObject, clickView );
        } catch (Exception e) {
            try {
                clickMethod.invoke( clickObject );
            } catch (Exception e1) {
                e1.printStackTrace();
            }
        }
    }
}
}

ViewFInder

public class ViewFinder {

  private Activity mActivity;
  private View mView;
  private byte viewType;

  public ViewFinder(View view) {
      this.mView = view;
      viewType = 0;
  }

  public ViewFinder(Activity activity) {
      this.mActivity = activity;
      viewType = 1;
  }

  public View findViewById(int viewId) {
      switch ( viewType ) {
          case 0:
              return mView.findViewById(viewId);
          case 1:
              return mActivity.findViewById(viewId);
      }
      return null;
  }

}

ViewId

@Target(ElementType.FIELD)
@Retention(RetentionPolicy.RUNTIME)
public @interface ViewId {
      int value();
}

OnClick

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface OnClick {
    int[] value();
}