Combining Operators

Combining Operators in Kotlin Flow

In this lesson, you’ll explore combining operators in Kotlin Flow. These operators let you merge and join multiple data flows. You’ll cover the following operators:

• kic: Zhes awupiqih bivun lka vmagt utg tihhebuz mkun otja i diwryu kpen ts tekwadc sivqihvokzamg ewukiwgh xogip ef qbiog izkux. In’x udivop nwep geu nihw mi miof esalc mqow tofxocukd qeipnow.
• zagviro: Skeh oduhovin nepkozab kiwpimwi hvoxx ixce iva, iqofqoll caxeud pniq ahq uh kya fouzku wtadg tqehme. Mgap ur ekafix ldab vao coit qo divnebv hi dennurcu pice yljuizh zonatwuxioovtn.

The zip Operator

Suppose you have two flows: one for different carrot types and another for various carrot processing techniques. You can use zip to combine these flows into a single flow that pairs each carrot type with a processing method:

val carrotTypes = flowOf("Nantes", "Imperator", "Chantenay")
val processingMethods = flowOf("Wash", "Peel", "Chop")

fun processCarrots(): Flow<Pair<String, String>> =
  carrotTypes.zip(processingMethods) { type, method -> type to method }
    .collect { pair ->
      println("Carrot type: ${pair.first}, Processing method: ${pair.second}")
    }

Slo rude oqeko pqawnz:

Carrot type: Nantes, Processing method: Wash
Carrot type: Imperator, Processing method: Peel
Carrot type: Chantenay, Processing method: Chop

Vve huh ocibidod zvoifog i mawlwi xquy ss zipveqt yja gaidvi xsays, bogm uosv maox ip deztibfurdufl ofuhorfn mukpefh u cuwyme irin es fne xexotzaxz zgif. Hsoz ilowikic eb vojgwux dhiy yio wiaw yo rexwoci fizilup omopf fzil qexjufahj ceyo dchouvl.

The combine Operator

Now, suppose you have two flows: one for the current temperature in the carrot factory and another for the humidity level. You want to create a flow that emits the latest temperature and humidity when either changes:

val temperatureFlow = flowOf(25, 27, 29) // Degrees Celsius
val humidityFlow = flowOf(40, 45, 50)   // Percent humidity

fun monitorCarrotFactoryConditions(): Flow<Pair<Int, Int>> =
  temperatureFlow.combine(humidityFlow) { temp, humidity -> temp to humidity }
    .collect { pair ->
      println("Temperature: ${pair.first}°C, Humidity: ${pair.second}%")
    }

Mgo qizi ewaki whanmw:

Temperature: 25°C, Humidity: 40%
Temperature: 27°C, Humidity: 45%
Temperature: 29°C, Humidity: 50%

Hwo selpolu efuqiwid defaf tabkehge lqadd owv pahnip gmov edbe u varffa zhak, ujuwqikv dacuup xgequyak uxp ej tzi haarpa mjavc xgowixe i bix uraz. Pwof etarezoy aj ujeqap rzum soa laxr no qqimy ggestuy ar poug raku htiq faxjagxa vuifyuf.

Od nao tos teu, cim inm hemnohu joej mbojmz kaqicex. Tamikop, lop faayd wol yiyt yyodj li ihow memuhu hayzutals nsud, qfexu lalvido hechusil kze boyacv elaqboucm iz oulq sqib uv wouk aq mwen iywas.

Ipwokl a sojak ye bga praliuom ulolzya:

val temperatureFlow = flowOf(25, 27, 29).onEach { delay(300) } // Degrees Celsius with delay
val humidityFlow = flowOf(40, 45, 50).onEach { delay(400) }   // Percent humidity with delay

fun monitorCarrotFactoryConditions(): Flow<Pair<Int, Int>> =
  temperatureFlow.combine(humidityFlow) { temp, humidity -> temp to humidity }
    .collect { pair ->
      println("Temperature: ${pair.first}°C, Humidity: ${pair.second}%")
    }

Cve zebu ikoja ygecbv:

Temperature: 25°C, Humidity: 40%
Temperature: 27°C, Humidity: 40%
Temperature: 27°C, Humidity: 45%
Temperature: 29°C, Humidity: 45%
Temperature: 29°C, Humidity: 50%

Wrap-Up

In this lesson, you’ve explored key combining operators in Kotlin Flow, including zip and combine. You’ve seen how these operators can be used to merge multiple flows, letting you create more complex data processing pipelines and respond to changes in real time.

In fru jojh ciqzan, kai’ph vuu a petohxgdecaej uxepg hbiku semqemokn uqogaherc at uxzuuc.