Hi, do Android people there know if it's possible ...

# coroutines

[louiscad]

Hi, do Android people there know if it's possible to make a Handler run in CommonPool?

[dalexander]

Doing a quick check of the documentation, it looks like in theory it's possible, but probably complicated and a bad idea. Handlers generally need a Looper to operate on. Since CommonPool represents a group of Threads, that means you'll have to initialize a Looper for each Thread (and you might want a custom LooperPool subclass, which I don't know if it exists, to do the dispatching). You would then be able to create a Handler on the Looper, but since Handlers aren't coroutine aware there's a risk that you end up just blocking the Thread the Handler is running on.

[mcastiblanco]

I don't think it would be safe/reliable because Handler is tied to a specific thread and the Kotlin runtime will decide which thread from the pool to use, which can change each time the suspending computation is resumed.

[mcastiblanco]

I guess using Handlers + coroutines would need a single thread context to be safe

[mcastiblanco]

but let us know your experience if you try to use it with CommonPool 🤣