Hi,
First of all, sorry for the very late response.
You are correct in assuming that the problem is caused by expired view state. But I'm not entirely
certain why it happens at the first place, because there's a polling process which periodically sends
a 'ping' request to the server, thereby keep the state alive.
Does it happen everytime? If so, you might want to open the developer console of your web browser
and monitor the ping process. The interval is 1 minute by default, so you should see a request in every
60 seconds per view that is opened in your browser.
Please let me know if you need further help. Thanks!
Cheers,
Xavier
2017년 1월 13일 금요일 오전 12시 39분 57초 UTC+9,
jeromebe...@gmail.com 님의 말: