上一篇文章中，我们已经成功的引入了Dagger2;今天我们将继续使用android MVP模式对代码进行实现。

1 将MainActivity.java文件移动到ui包下，并在ui包下建立view包； view包下存放接口。包及类结构如图

1.png

2 新建presenter包，并在presenter下建立相关的类， 如图

2.png

• 说明：图中RxMapPresenter为Presenter的基类， 该类继承BaseMapPresenter类； BaseMapPresenter提供子类实例化Presenter与View之间的接口对象的方法。RxMapPresenter 负责实例化CompositeSubscription对象， 子类使用该对象进行网络请求。

MainActivity.java代码如下

public class MainActivity extends BaseAcitvity implements MainView, HasComponent<MainComponent> {

    @BindView(R.id.test)
    TextView test;

    @Inject
    MainPresenter mainPresenter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ButterKnife.bind(this);
        getComponent().inject(this);

        //重要
        mainPresenter.attachView(this);
    }


    @OnClick(R.id.test)
    public void onClick() {
        mainPresenter.login("", "");
    }

    @Override
    public void loginSuccess(String userInfo) {
        Toast.makeText(this, userInfo, Toast.LENGTH_LONG).show();
    }

    @Override
    public void loginFail() {

    }

    @Override
    public void loginException() {

    }

    @Override
    public MainComponent getComponent() {
        return DaggerMainComponent.builder()
                .applicationComponent(Application.get(this).getComponent())
                .activityModule(new ActivityModule(this))
                .mainModule(new MainModule())
                .build();
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        mainPresenter.detachView();
    }
}

BaseAcitvity.java

public class BaseAcitvity extends Activity {
    private ActivityComponent mActivityComponent;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    public ActivityComponent getActivityComponent() {
        if (mActivityComponent == null) {
            mActivityComponent = DaggerActivityComponent.builder()
                    .activityModule(new ActivityModule(this))
                    .applicationComponent(Application.get(this).getComponent())
                    .build();
        }
        return mActivityComponent;
    }
}

MainView.java

public interface MainView extends MvpView{
    void loginSuccess(String userInfo);
    void loginFail();
    void loginException();
}

HasComponent.java

public interface HasComponent<C> {

    C getComponent();
}

MainPresenter .java

public class MainPresenter extends RxMvpPresenter<MainView> {

    @Inject
    public MainPresenter() {

    }

    @Inject
    Application context;

    public void login(String username, String password) {
        getMvpView().loginSuccess("MVP成功搭建");
    }
}

RxMvpPresenter.java

public class RxMvpPresenter<V extends MvpView> extends BaseMvpPresenter<V> {

    protected CompositeSubscription mCompositeSubscription;

    @Override
    public void attachView(V mvpView) {
        super.attachView(mvpView);

        mCompositeSubscription = new CompositeSubscription();
    }

    @Override
    public void detachView() {
        super.detachView();

        mCompositeSubscription.clear();
        mCompositeSubscription = null;
    }
}

BaseMvpPresenter.java

public class BaseMvpPresenter<V> implements MvpPresenter<V> {

    private V mMvpView;

    @Override
    public void attachView(V mvpView) {
        mMvpView = mvpView;
    }

    @Override
    public void detachView() {
        mMvpView = null;
    }

    public boolean isViewAttached() {
        return mMvpView != null;
    }

    public V getMvpView() {
        return mMvpView;
    }

    public void checkViewAttached() {
        if (!isViewAttached()) throw new MvpViewNotAttachedException();
    }

    public static class MvpViewNotAttachedException extends RuntimeException {
        public MvpViewNotAttachedException() {
            super("Please call Presenter.attachView(MvpView) before" +
                    " requesting data to the Presenter");
        }
    }
}

MvpPresenter.java

public interface MvpPresenter<V> {


    @UiThread
    void attachView(V view);


    @UiThread
    void detachView();

}

BaseAcitvity.java

public class BaseAcitvity extends Activity {
    private ActivityComponent mActivityComponent;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    public ActivityComponent getActivityComponent() {
        if (mActivityComponent == null) {
            mActivityComponent = DaggerActivityComponent.builder()
                    .activityModule(new ActivityModule(this))
                    .applicationComponent(Application.get(this).getComponent())
                    .build();
        }
        return mActivityComponent;
    }
}

MvpView.java

public interface MvpView {
}

3. 运行项目， 点击屏幕上的HelloWold！文字， 如果出现 “MVP搭建成功”的文字说明android MVP环境搭建成功,如图：。

3.png
下一篇我们将讲解如何引入Retrofit RxJava

项目下载地址