FlowOn for changing dispatcher in Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to switch the flow to the IO dispatcher.

Kotlin

flowOf(1, 2, 3).[1](Dispatchers.IO)

Drag options to blanks, or click blank then click option'

Acollect

BflowOn

Cmap

Dfilter

Attempts:

3 left

💡 Hint

Common Mistakes

Using collect instead of flowOn.

Using map or filter which do not change dispatcher.

The flowOn operator changes the dispatcher where the flow is executed.

2fill in blank

medium

Complete the code to collect the flow on the Main dispatcher.

Kotlin

flowOf("A", "B", "C").flowOn(Dispatchers.IO).[1] { value -> println(value) }

Drag options to blanks, or click blank then click option'

Acollect

Bmap

Cfilter

DlaunchIn

Attempts:

3 left

💡 Hint

Common Mistakes

Using map or filter which transform but do not collect.

Using launchIn which requires a CoroutineScope.

collect is used to receive the emitted values from the flow.

3fill in blank

hard

Fix the error in the code to correctly change the dispatcher.

Kotlin

val flow = flow {
    emit(10)
}.[1](Dispatchers.Default)

flow.collect { println(it) }

Drag options to blanks, or click blank then click option'

AflowOn

Bcollect

ClaunchIn

Dmap

Attempts:

3 left

💡 Hint

Common Mistakes

Using collect instead of flowOn to change dispatcher.

Using launchIn without a CoroutineScope.

flowOn must be used to change the dispatcher of the flow emissions.

4fill in blank

hard

Fill both blanks to create a flow that emits numbers on IO dispatcher and collects on Main dispatcher.

Kotlin

flow {
    emit(1)
    emit(2)
}.[1](Dispatchers.IO).[2] { value -> println(value) }

Drag options to blanks, or click blank then click option'

AflowOn

Bmap

Ccollect

Dfilter

Attempts:

3 left

💡 Hint

Common Mistakes

Using map or filter instead of collect to receive values.

Using collect before flowOn.

flowOn changes the dispatcher for emission, collect receives the values.

5fill in blank

hard

Fill all three blanks to create a flow that emits strings on Default dispatcher, maps them to uppercase, and collects on IO dispatcher.

Kotlin

flowOf("a", "b", "c").[1](Dispatchers.Default).[2] { it.[3]() }.collect { println(it) }

Drag options to blanks, or click blank then click option'

AflowOn

Bmap

Cuppercase

Dfilter

Attempts:

3 left

💡 Hint

Common Mistakes

Using filter instead of map for transformation.

Using lowercase instead of uppercase.

flowOn changes dispatcher, map transforms each item, uppercase converts string to uppercase.