Android 开发使用MVP结合RxJava产生内存泄漏的解决

在上一篇我们说道，MVP中由于P对V（Activity）的引用可能导致内存泄漏。
我们都知道，当我们使用非静态内部类，或者匿名内部类的时候，由于内部类会默认持有外部类的引用，当我们在内部类中进行耗时操作时，就会长时间保持对外部类的引用导致资源无法释放产生泄漏的可能。
下面Presenter的基类，我们将P对V的引用改成了弱引用的方式，同时结合Acitivty的生命周期去进行attachView和dettach，解除P、V的绑定。

public class BasePresenter<T> {
    public Reference<T> mViewRef;
    protected CompositeSubscription mCompositeSubscription;
    public void attachView(T mView){
        mCompositeSubscription = new CompositeSubscription();
        mViewRef = new WeakReference<>(mView);
    }
    public T getView(){
        if (mViewRef!=null) {
            return mViewRef.get();
        }
        return null;
    }
    public void dettach(){
        if (mCompositeSubscription!=null&&mCompositeSubscription.isUnsubscribed()){
            mCompositeSubscription.unsubscribe();
        }
        if (mViewRef!=null){
            mViewRef.clear();
            mViewRef=null;
        }
    }
}

下面Activity的基类，可以看到在基类Acitivity中我们将P根据生命周期进行了绑定和解绑工作

public abstract class BaseMvpActivity<V,T extends BasePresenter<V>> extends SwipeBackActivity {

    private T presenter;

    @SuppressWarnings(value = {"unchecked"})
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        presenter = initPresenter();
        presenter.attachView((V)this);
    }

    protected abstract T initPresenter();

    @Override
    protected void onDestroy() {
        super.onDestroy();
        presenter.dettach();
        presenter=null;
    }
}

这样我们在PresenterImpl和Activiity中，就很明了了

public class TestDetailPresenterImpl extends BasePresenter<TestDetailView>{

    private TestDetailModel testDetailModel;

    public TestDetailPresenterImpl(){
        testDetailModel = new TestDetailModelImpl();
    }

    public void loadTest(String topicId,String userid) {
        Subscription testSubscription = testDetailModel.loadTest(topicId, userid)
                .observeOn(AndroidSchedulers.mainThread())
                .subscribeOn(Schedulers.io())
                .subscribe(new Subscriber<SubjectBean>() {
                    @Override
                    public void onCompleted() {

                    }

                    @Override
                    public void onError(Throwable e) {
                        if (e != null&&getView()!=null) {
                            getView().showLoadResult(e.getMessage());
                        }
                    }

                    @Override
                    public void onNext(SubjectBean subjectBean) {
                        SubjectBean.ObjectBean objectBean = subjectBean.getObject();
                         if (getView()!=null) {
                            getView().addTestData(objectBean);
                        }
                    }
                });
        mCompositeSubscription.add(testSubscription);
    }

public class TestDetailActivity extends BaseMvpActivity<TestDetailView,TestDetailPresenterImpl> implements TestDetailView {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_test_detail);
    
    }

    @Override
    protected TestDetailPresenterImpl initPresenter() {
        testDetailPresenter = new TestDetailPresenterImpl();
        return testDetailPresenter;
    }

这样我们就基本解决了MVP导致的内存泄漏问题