上一个Demo是为了让初识MVP的同学在总体上有一个了解，了解大概的运行流程，Demo很不规范和粗暴。
对于MVP框架，Google也有自己的Demo。下面我就按照Google的代码规范一下上次的那个例子。GoogleMVPDemo
BaseView
public interface BaseView<T> {
void setPresenter(T presenter);
}
BasePresenter
public interface BasePresenter<T> {
void start();
}
Contarct(契约类)
Google的Demo中多了一个契约类，并且将所需要的接口都写在里面，方便开发者查看V和P中的方法有哪些。
public interface Contarct {
interface View extends BaseView<Presenter> {
void showLoading();
void hideLoading();
void setListItem(List<String> data);
void failed();
void showMessage(String message);
}
interface Presenter extends BasePresenter {
void itemclick(int position);
}
}
OK！接下来就是MVP三部分的实现了。
M
这次偷懒直接将数据获取写在了P中。所以没有用到。
P
public class MvpPresenter implements Contarct.Presenter {
private Contarct.View MvpView;
//在Google_MVP_Demo中使用了Fragemnt所以初始化P对象是在Activity中
public MvpPresenter(Contarct.View mvpView) {
MvpView = mvpView;
MvpView.setPresenter(this);
}
//在Google_MVP_Demo中是在Fragment中开始执行start操作
@Override
public void start() {
MvpView.showLoading();
GetData();//获取数据
}
//模拟数据处理
List data = new ArrayList();
private void GetData() {
Observable.create(new ObservableOnSubscribe<List<String>>() {
@Override
public void subscribe(@NonNull ObservableEmitter<List<String>> e) throws Exception {
for (int i = 0; i < 50; i++) {
data.add(i + "items");
}
e.onNext(data);
}
}).subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.subscribe(new Observer<List<String>>() {
@Override
public void onSubscribe(Disposable d) {
}
@Override
public void onNext(List<String> strings) {
MvpView.hideLoading();
MvpView.setListItem(data);//数据获取成功
}
@Override
public void onError(Throwable e) {
MvpView.failed();
}
@Override
public void onComplete() {
}
});
}
@Override
public void itemclick(int position) {
MvpView.showMessage("点击了item" + position);
}
V
一个Activity展示一个列表，在Google_MVP_Demo中是Fragment。
public class MvpActivity extends AppCompatActivity implements Contarct.View, AdapterView.OnItemClickListener {
private ListView mvpListView;
private Contarct.Presenter mPresenter;
private ProgressBar pb;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_mvp);
mvpListView = (ListView) findViewById(R.id.mvp_listview);
mvpListView.setOnItemClickListener(this);
pb = (ProgressBar) findViewById(R.id.mvp_loading);
new MvpPresenter(this);
mPresenter.start();
}
@Override
public void showLoading() {
pb.setVisibility(View.VISIBLE);
}
@Override
public void hideLoading() {
pb.setVisibility(View.GONE);
}
@Override
public void setListItem(List<String> data) {
ArrayAdapter adapter = new ArrayAdapter(MvpActivity.this, android.R.layout.simple_list_item_1, data);
mvpListView.setAdapter(adapter);
}
@Override
public void failed() {
Toast.makeText(MvpActivity.this, "加载失败", Toast.LENGTH_SHORT).show();
}
@Override
public void showMessage(String message) {
Toast.makeText(this, message, Toast.LENGTH_SHORT).show();
}
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
mPresenter.itemclick(position);
}
@Override
public void setPresenter(Contarct.Presenter presenter) {
this.mPresenter = presenter;
}
