onCardActive.kt

    fun onCardActive(currencyId: Int, index: Int) {
        if (producers.containsKey(currencyId)) return
        val currencyPriceUpdateFlow: Flow<Int> = provideCurrencyUpdateFlow()
        val currencyPriceUpdateJob = viewModelScope.launch {
            observePriceUpdateFlow(index, currencyPriceUpdateFlow)
        }
        producers[currencyId] = currencyPriceUpdateJob
    }