Please, Without using Android, is there a way i can switch context to a main thread inside a launch {} ?

it is the same way as on android -- unless you're not using JavaFX/Swing/etc., and in that case you would need to implement the MainDispatcher yourself to indicate to Kotlin which thread is your "main" thread

Yeah, i'm neither using JavaFX or Swing... can you guide me on how to implement a main dispatcher perhaps a link will help.

Since you can't dispatch back to the first thread (the thread that called the

main

function) on non-UI application due to the lack of an event loop, you could use

newSingleThreadContext()

to create a dispatcher to use as your main thread. Note that you'll have to block the first thread (with

runBlocking

and

withContext

, or using

launch

and awaiting on the resulting job), otherwise the program will terminate.

https://gist.github.com/octylFractal/4fb0ff0fe7fb25cb26d173ba1b3fcbf1 is a small + quick sample for a main dispatcher that does dispatch back to the main thread

Alright... That made me feel like a dummy 🤦‍♂️ . I'm disappointed at my efforts in coding, like how did you come up with that so quick, how did you know about

ArbitraryMainDispatcher

etc... What am i not reading right?

well, I just wrote

ArbitraryMainDispatcher

based on the

JavaFX

main dispatcher, and gave it

queue(Runnable)

as a stand-in for JavaFX's

Platform.runLater(Runnable)

. The main part is knowing that

MainCoroutineDispatcher

exists

Alright, followed you on keybase.! thanks

Don't feel bad about it @paulex, I thought I knew a lot about coroutines until I saw @octylFractal's answer. Let's learn from each other!

The coroutines library already provides a binding of

Dispatchers.Main

for javafx, is there some reason you can't use that? https://github.com/Kotlin/kotlinx.coroutines/blob/master/ui/kotlinx-coroutines-javafx/README.md

because they're not using JavaFX: https://kotlinlang.slack.com/archives/C1CFAFJSK/p1585125021004100

Oops, I missed the “neither”, my bad