Error: Only the original thread that created a view hierarchy can touch its views

Hi everyone,

Reposting from

One of our users is receiving an error when attempting to add us as an issuer to his Blockcerts wallet (Android). After entering our issuer URL, entering his one-time code, and tapping “Add Issuer,” he gets:

“Only the original thread that created a view hierarchy can touch its views.”

He has tried multiple times, over multiple days, and gets this error each time. Other users have been able to add us as an issuer with no errors during this same time frame.

Does this error ring any bells for anyone?

Very weird. Sounds like it could be an android version / model bug going on. Haven’t seen that one myself. Do you have any device information?

He reports that he’s using Pixel 2, Android version 9.

FYI… I just received the same report from a user on a OnePlus 5 running Android 9. Perhaps this is an issue with Android 9?

I know other users with Android 9 do not have this problem and I haven’t seen/heard of this error myself. Could be a bit more specific than just Android 9. Could you provide a bit more information on this error? How does it appear - does it show in the logs or it is visually displayed back to the user? Does the whole app crash afterwards?

Wow, as soon as I say that, I reproduced the error on my android phone (Nexus v7) when I put in some garbage values like “” for the issuer and “t” for the token. I emailed the logs to myself so I’ll try to take a look at it.

Edit: even reproduced it by using good values