片段和活動中runBlockingCoroutines的替代品是什么？

建議不要使用 GlobalScope 和 runBlocking。為了這個主題，我已經實施了更改： End flow/coroutines task before go further null issue

但是，它不像以前那樣與 runBlocking 一起作業。簡而言之，圖示不變，資料不準時。我的情況是根據布林值更改圖示。

Flow 用例

class GetNotificationListItemDetailsUseCase @Inject constructor(private val notificationDao: NotificationDao): BaseFlowUseCase<Unit, List<NotificationItemsResponse.NotificationItemData>>() {
    override fun create(params: Unit): Flow<List<NotificationItemsResponse.NotificationItemData>> {
        return flow{
            emit(notificationDao.readAllData())
        }
    }
}

視圖模型

    val actualNotificationList: Flow<List<NotificationItemsResponse.NotificationItemData>> = getNotificationListItemDetailsUseCase.build(Unit)
    

分段

    private fun getActualNotificationList() : Boolean {
        lifecycleScope.launch {
            vm.actualNotificationList
                .flowWithLifecycle(lifecycle, Lifecycle.State.STARTED)
                .collect { response ->
                    notificationData.value = response
                    val notificationDataString = notificationData.value.toString()
                    val stringToCheck = "isRead=false"
                    isNotificationNotRead = (notificationDataString.contains(stringToCheck))
                }
        }
        return isNotificationNotRead
    }

在方法 onViewCreated 我有 initToolbar 來檢查它是否為真并采取行動，runBlokcing 作業。

fun initToolbar{
        if (onReceived) {
            Log.d("onReceivedGoes", "GOES IF")
        } else {
            Log.d("onReceivedGoes", "GOES ELSE")
            getActualNotificationList()
        }
        onReceived = false

        val item = menu.findItem(R.id.action_notification_list)
        when {
            isNotificationNotRead && !isOutcomed -> {
                item.setIcon(R.drawable.image_icon_change)
            }
}

更改之前的協程作業，效果很好

        val job = GlobalScope.launch {
            vm.getNotificationListItemDetailsUseCase.build(Unit).collect {
                notificationData.value = it
                val notificationDataString = notificationData.value.toString()
                val stringToCheck = "isRead=false"
                isNotificationNotRead = (notificationDataString.contains(stringToCheck))
            }
        }
        runBlocking {
            job.join()
        }
    }

另一個問題是我在 MainActivity 中也有同樣的事情要做，但我不在那里使用流程只是暫停功能。

用例

class UpdateNotificationListItemUseCase @Inject constructor(private val notificationDao: NotificationDao): BaseUpdateBooleanUseCase<Int, Boolean, Boolean, Boolean, Unit>() {
    override suspend fun create(itemId: Int, isRead: Boolean, isArchived: Boolean, isAccepted: Boolean){
        notificationDao.updateBooleans(itemId, isRead, isArchived, isAccepted)
    }
}

主要活動

            val job = GlobalScope.launch { vm.getIdWithUpdate() }
            runBlocking {
                job.join()
            }

主視圖模型

suspend fun getIdWithUpdate() {
        var id = ""
        id = notificationAppSessionStorage.getString(
            notificationAppSessionStorage.getIncomingKeyValueStorage(),
            ""
        )
        if (id != "") {
           
            updateNotificationListItemUseCase.build(id.toInt(), true, false, false)
        }
    }
}

編輯1：

收集碎片效果很好，謝謝

怎么樣 MainActivity 和使用這個用例與暫停樂趣沒有流動。

我已閱讀檔案https://developer.android.com/kotlin/coroutines/coroutines-best-practices

        val IODispatcher: CoroutineDispatcher = Dispatchers.IO
        val externalScope: CoroutineScope = CoroutineScope(IODispatcher)
            suspend {
                externalScope.launch(IODispatcher) {
                    vm.getIdWithUpdate()
                }.join()
            }

第二種選擇，但在這里我不等到作業完成

            suspend {
                withContext(Dispatchers.IO) {
                    vm.getIdWithUpdate()
                }
            }

你怎么看待這件事？

uj5u.com熱心網友回復：

您可以嘗試更新collect塊中的圖示：

private fun getActualNotificationList() = lifecycleScope.launch {
        vm.actualNotificationList
            .flowWithLifecycle(lifecycle, Lifecycle.State.STARTED)
            .collect { response ->
                notificationData.value = response
                val notificationDataString = notificationData.value.toString()
                val stringToCheck = "isRead=false"
                val isNotificationNotRead = (notificationDataString.contains(stringToCheck))

                val item = menu.findItem(R.id.action_notification_list)
                when {
                    isNotificationNotRead && !isOutcomed -> {
                        item.setIcon(R.drawable.image_icon_change)
                    }
                }
            }
}

使用runBlocking您正在阻塞Main Thread，這可能會導致ANR。

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