Library support for Kotlin coroutines in Kotlin/JVM and Kotlin/JS
Questions tagged [kotlinx.coroutines]
296 questions
44
votes
3 answers
Suspend function 'callGetApi' should be called only from a coroutine or another suspend function
I am calling suspended function from onCreate(...)
override fun onCreate(savedInstanceState: Bundle?) {
...
...
callGetApi()
}
and the suspended function is:-
suspend fun callGetApi() {....}
But the error shows up Suspend function…
Santanu Sur
- 8,836
- 7
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- 43
36
votes
6 answers
Kotlin Coroutines with returning value
I want to create a coroutine method which has returning value.
For example)
fun funA() = async(CommonPool) {
return 1
}
fun funB() = async(CommonPool) {
return 2
}
fun sum() {
launch {
val total = funA().await() +…
Expert wanna be
- 8,490
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- 98
- 148
34
votes
9 answers
Module with Main dispatcher is missing
I'm trying to make a background call to my local database and update the UI with the results using coroutines.
Here is my relevant code:
import kotlinx.coroutines.experimental.*
import kotlinx.coroutines.experimental.Dispatchers.IO
import…
Khongor Bayarsaikhan
- 1,266
- 1
- 10
- 16
31
votes
11 answers
Kotlin Android debounce
Is there any fancy way to implement debounce logic with Kotlin Android?
I'm not using Rx in project.
There is a way in Java, but it is too big as for me here.
Kyryl Zotov
- 1,366
- 2
- 19
- 38
28
votes
3 answers
Why not use GlobalScope.launch?
I read that usage of Globalscope is highly discouraged, here.
I have a simple use-case. For every kafka message (let's say a list of Ids) that I receive I have to split it and invoke a rest service simultaneously and wait for it to be done and…
so-random-dude
- 12,394
- 9
- 47
- 96
18
votes
2 answers
Using kotlinx.coroutines in IntelliJ IDEA project
I am trying to learn coroutines and so I fire up IntelliJ and create a scratch file. But when I type in my coroutines I get compiler complaints such as runBlocking is an unresolved reference. So this is not an android project or any such thing. Just…
salyela
- 757
- 2
- 7
- 18
17
votes
3 answers
Room with Kotlin-coroutines observe db changes
So, I recently started experimentation with coroutines, I switched from Rxjava2 to coroutines, I haven't got a grasp of it yet but still, I ran into a condition where I needed to observe my database change and update the UI corresponding to…
Rajat Beck
- 1,233
- 10
- 24
15
votes
2 answers
How to launch a Kotlin coroutine in a `suspend fun` that uses the current parent Scope?
How can I launch a coroutine from a suspend function and have it use the current Scope? (so that the Scope doesn't end until the launched coroutine also ends)
I'd like to write something like the following –
import kotlinx.coroutines.*
fun main() =…
Rusty Fieldstone
- 633
- 5
- 15
15
votes
4 answers
How to transform an Android Task to a Kotlin Deferred?
Firebase anonymous sign in returns a task (which is basically Google promise implementation):
val task:Task = FirebaseAuth.getInstance().signInAnonymously()
How it would be possible create a signInAnonymous wrapper where:
It is a…
JP Ventura
- 4,663
- 5
- 43
- 62
15
votes
3 answers
Kotlin Coroutines in a Android Service
I have a android service which starts and syncs different types of data with the server when it's online.
I'm new to Kotlin coroutines and I'm trying to accomplish the following:
fun syncData{
//Job1 make retrofit call to server
//Job2 make retrofit…
julioribeiro
- 973
- 1
- 10
- 20
14
votes
1 answer
Using coroutines in retrofit authenticator
I'm trying to implement JWT token authentication and refresh token in retrofit using coroutines. The tokens are stored in a Room database. How should I implement the await call?
Currently I'm using runBlocking {...} call to wait for the async…
Mihirrai
- 145
- 1
- 4
14
votes
2 answers
Error calling Dispatchers.setMain() in unit test
Have started to try to use kotlinx-coroutines-test (https://github.com/Kotlin/kotlinx.coroutines/blob/master/core/kotlinx-coroutines-test/README.md) in JUnit unit test but getting following error when i call…
John O'Reilly
- 8,536
- 4
- 31
- 49
14
votes
2 answers
Whats the concept behind a CoroutineScope?
After reading the introduction and the javadoc of CoroutineScope I'm still a little confused what the idea behind a CoroutineScope is.
The first sentence of the doc "Defines a scope for new coroutines." is not clear to me: Why do my coroutines need…
morpheus05
- 4,461
- 2
- 26
- 46
14
votes
1 answer
Kotlin Coroutine Unit Testing Error: Exception in thread "main @coroutine#1 @coroutine#2" java.lang.NullPointerException
I'm trying to unit test a presenter that I made with Kotlin coroutines, and this is also my first time using Mockito
Whenever I try to run the unit test I'm getting the following error the first time it tries to do anything with my view while in the…
Ben987654
- 2,534
- 2
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- 41
13
votes
1 answer
How to call Kotlin suspending coroutine function from Java 7
I'm trying to call Kotlin function from Java 7. I'm using coroutines and this called function is suspending, for example:
suspend fun suspendingFunction(): Boolean {
return async { longRunningFunction() }.await()
}
suspend fun…
michalbrz
- 2,702
- 1
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