I am trying to run demo given here. The problem is whenever app tries to register instanceId, it say "background sync failed: MISSING_INSTANCEID_SERVICE, retry in 320s" and then when I print token, it says token is null. I tried changing INSTANCE_ID_EVENTinstead of INSTANCEID_EVENT and other solution that were previously asked on stackoverflow, but none of them works for me.
See Question&Answers more detail:
os 与恶龙缠斗过久,自身亦成为恶龙；凝视深渊过久,深渊将回以凝视…
