总的来说，我是 Android 和 MVP 的新手，过去 1.5 年我一直在做 iOS 编程，所以我发现委托模式很容易理解。我以视图符合演示者协议的方式实现了 MVP，这让演示者可以忽略视图的特定类型，但让它知道某些方法是给定的，因此可以调用“视图”。我一直在阅读各种 MVP 指南和所有 Mosby 教程，但我不确定我是否同意其中的一些内容。我实施的模式是洁净的吗？我想要一些反馈，这样我就不会一直朝着错误的方向前进，如果这确实是我正在做的...
例如，
基地主讲人：
public abstract class Presenter<V, S> implements BasePresenterInterface<V, S> {
public interface PresenterProtocol extends BasePresenterProtocol {
}
private WeakReference<V> mAttachedView = null;
private S mService = null;
/**
* Interface Overrides
*/
@Override
public void attachView(V view) {
boolean viewDoesNotConform = !viewDoesConform(view);
if (viewDoesNotConform) {
Log.d("DEBUG", "Cannot attach View that does not conform to PresenterProtocol");
return;
}
mAttachedView = new WeakReference<>(view);
((BasePresenterProtocol) getAttachedView()).onViewAttached();
}
@Override
public void detachView() {
mAttachedView = null;
}
@Override
public boolean viewDoesConform(V view) {
Class<?> klass = view.getClass();
boolean conforms = BasePresenterInterface.BasePresenterProtocol.class.isAssignableFrom(klass);
return conforms;
}
@Override
public boolean viewIsAttached() {
return mAttachedView != null;
}
@Override
public V getAttachedView() {
return mAttachedView.get();
}
@Override
public S getService() {
return mService;
}
@Override
public void setService(S service) {
mService = service;
}
}
然后，我将其子类化为以下内容：
PhotoRecyclerPresenter:
public class PhotoRecyclerPresenter extends Presenter<PhotoRecyclerPresenter.PhotoRecyclerPresenterProtocol, PhotoService> {
public interface PhotoRecyclerPresenterProtocol extends Presenter.PresenterProtocol {
void onPhotosLoaded(List<TestPhoto> photoList);
void onItemSelected(TestPhoto photo);
void onShowDetail(TestPhoto photo);
}
private static PhotoRecyclerPresenter mSharedInstance;
private PhotoRecyclerPresenter() {
setService(new PhotoService());
}
/**
* External Methods
*/
public void getPhotos() {
boolean noAttachedView = !viewIsAttached();
if (noAttachedView) {
Log.d("DEBUG", "No view attached");
return;
}
getService().getAPI()
.getPhotos()
.observeOn(AndroidSchedulers.mainThread())
.subscribe(photoList -> getAttachedView().onPhotosLoaded(photoList));
}
/**
* Internal Methods
*/
public static PhotoRecyclerPresenter getSharedInstance() {
boolean firstInstance = mSharedInstance == null;
if (firstInstance) {
setSharedInstance(new PhotoRecyclerPresenter());
}
return mSharedInstance;
}
public static void setSharedInstance(PhotoRecyclerPresenter instance) {
mSharedInstance = instance;
}
public void didSelectItem(TestPhoto photo) {
getAttachedView().showDetail(photo);
}
}
它与视图通信： PhotoRecyclerFragment：
public class PhotoRecyclerFragment extends Fragment implements PhotoRecyclerPresenter.PhotoRecyclerPresenterProtocol {
private RecyclerView mRecyclerView;
private RecyclerView.LayoutManager mLayoutManager;
private Activity mParentActivity;
private PhotoRecyclerPresenter mPresenter;
private PhotoRecyclerAdapter mAdapter;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_recycler, container, false);
mParentActivity = getActivity();
mRecyclerView = (RecyclerView) rootView.findViewById(R.id.recyclerView);
mLayoutManager = new LinearLayoutManager(mParentActivity);
mAdapter = new PhotoRecyclerAdapter(this);
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.setAdapter(mAdapter);
mPresenter = PhotoRecyclerPresenter.getSharedInstance();
mPresenter.attachView(this);
return rootView;
}
@Override
public void onDestroyView() {
super.onDestroyView();
mPresenter.detachView();
mAdapter.clear();
}
/**
* PhotoRecyclerPresenterProtocol Methods
*/
@Override
public void onItemSelected(TestPhoto photo) {
mPresenter.didSelectItem(photo);
}
@Override
public void onPhotosLoaded(List<TestPhoto> photoList) {
mAdapter.loadPhotos(photoList);
}
@Override
public void onViewAttached() {
mPresenter.getPhotos();
}
@Override
public void onViewDetached() {
}
@Override
public void onShowDetail(TestPhoto photo) {
Intent detailIntent = new Intent(mParentActivity, PhotoDetailActivity.class);
mParentActivity.startActivity(detailIntent.putExtra(Intent.EXTRA_UID, photo.getPhotoId()));
}
}
这让我可以定义视图需要遵守的一组要求，以便使用单例演示者，同时让演示者不知道哪些视图使用它，只要它们符合其协议。到目前为止，在我的实践项目中，它似乎工作得很好，但我似乎找不到任何资源可以推荐我正在做的事情，就 MVP 而言，我有足够的自我怀疑，我想我会问我的第一个 StackOverflow 问题。任何有 MVP 经验的人都可以对此有所了解吗？
另外，如果我在错误的地方提问，请随时将我指向正确的地方发布此内容。
谢谢 ：）