雖然rxjava很好用, 如果產生過多的訂閱就會造成記憶體洩漏問題, 如何解決呢?

@Override
    protected void onDestroy() {
        super.onDestroy();
        //主動解除訂閱關係
        if (mSubscription != null && !mSubscription.isUnsubscribed()) {
            mSubscription.unsubscribe();
        }
    }

mSubcsription是 被觀察者訂閱觀察者的返回值;

Subscription subscription = Observable.from
 
(list)
                .filter(new Func1<User, Boolean>() {
                    @Override
                    public Boolean call(User user) {
                        return !user.id.equals("2");
                    }
                })
//                .elementAt(3)//只打印出index為3的元素
                .subscribeOn
 
(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(new Action1<User>() {
                    @Override
                    public void call(User user) {

                        System.out.println("MainActivity.call=" + user.id);
                    }
                });