android - 更新 Room 数据库时未触发 LiveData

Question

我有ViewPager2 个片段。当列表在一个片段上更新时，它应该反映另一个片段上的更改。

这就是我Dao的更新方法的样子

@Query("SELECT * FROM ${Constants.KAFANI_TABLE_NAME} WHERE isFavorite = 1")
fun getFavoriteKafani(): Single<MutableList<Kafana>>
@Query("UPDATE ${Constants.KAFANI_TABLE_NAME} SET isFavorite = :isFavorite WHERE id = :id")
fun setFavourite(id: Int, isFavorite: Int)

然后，我在我的内部调用这些方法repository

fun getFavoriteKafani(): Single<MutableList<Kafana>> {
    return kafanaDao.getFavoriteKafani()
}
fun setKafanaFavorite(kafana: Kafana, isFavorite: Int): Completable = Completable.fromCallable {
    kafanaDao.setFavourite(kafana.id, isFavorite)
}

我的ViewModel

fun setFavorite(kafana: Kafana, isFavorite: Int) {
    compositeDisposable.addAll(kafanaRepository
            .setKafanaFavorite(kafana, isFavorite)
            .compose(scheduler.getSchedulersForCompletable())
            .subscribeBy(
                    onComplete = {
                        sendFavoriteUpdate(1)
                        Timber.d("${Constants.KAFANA_APP_TAG} Added as favorite ${kafana.name}")
                    },
                    onError = {
                        Timber.d("${Constants.KAFANA_APP_TAG} setFavorite onError ${it.localizedMessage}")
                    }
            ))

}

fun loadFavoriteKafani() {
    compositeDisposable.addAll(kafanaRepository
            .getFavoriteKafani()
            .compose(scheduler.getSchedulersForSingle())
            .subscribeBy(
                    onSuccess = {
                        if (it.isEmpty()) {
                            isFavoriteEmpty.set(true)
                            Timber.d("${Constants.KAFANA_APP_TAG} loadFavoriteKafani listIsEmpty")
                        } else {
                            kafaniList.value = it
                            isFavoriteEmpty.set(false)
                            Timber.d("${Constants.KAFANA_APP_TAG} loadFavoriteKafani listNotEmpty")
                        }
                    },
                    onError = {
                        isFavoriteEmpty.set(true)
                        Timber.d("${Constants.KAFANA_APP_TAG} loadFavoriteKafani OnError: $it.localizedMessage")
                    }))
}

最后在我的fragment

private fun getFavoriteKafani() {
    viewModel.loadFavoriteKafani()
    viewModel.kafaniList.observe(this, Observer<MutableList<Kafana>> {
        it?.let {
            sorted = it.sortedWith(compareBy({ !it.isSponsored }, { it.name })).toMutableList()
            kafanaAdapter = KafanaAdapter(sorted, this, 2)
            binder.rvKafani.adapter = kafanaAdapter
        }
    })
}

但是，每当我在一个片段中将 kafana 设置为收藏夹时，该列表不会在另一个片段中触发。

标签： androidandroid-fragmentsandroid-roomandroid-livedata