Glide cache image on disk on background thread

Question

I want to use Glide to eagerly download images and cache them on disk for a future use. I want to call this functionality from a background thread.

I've read Glide's caching documentation, but it doesn't explain how to download the image without having an actual target right now. Then I found this issue and tried to use a similar approach, but whatever I try I get this exception:

java.lang.IllegalArgumentException: You must call this method on the main thread

So, how can I tell Glide to cache an image from a background thread?

EDIT: I really want to call Glide's methods on background thread. I know that I can use Handler and other ways to offload it to UI thread, but that's not what I'm asking.

Answer 1

GlideApp.with(context)
    .downloadOnly()
    .diskCacheStrategy(DiskCacheStrategy.DATA) // Cache resource before it's decoded
    .load(url)
    .submit(Target.SIZE_ORIGINAL, Target.SIZE_ORIGINAL)
    .get() // Called on background thread