I am using UNCalendarNotificationTrigger and from my initial tests with simulator and timezone changes in my mac i see that notification donot get triggered at specific times if timezone changes, is this expected behaviour ?
Does UNCalendarNotificationTrigger fire at the same time everyday even if user changes his timezone ?
UNCalendarNotificationTrigger specifically will fire at a specific time and date.
If you do not specify the timeZone component of DateComponents, it will fire when the specified DateComponents match the actual time. If you specify the time zone, then it would be expected that the trigger will be fixed to the time zone - in other words, will float as far as the traveling phone is concerned.
That is not the behavior I see. When I schedule a local notification with UNCalendarNotificationTrigger and only specify the hour and minute in the date component it still locks to an absolute time based on the timezone when scheduled. For example, I set the phone's timezone to PST and schedule a local notification to fire at 9:00 AM - the date component only sets hours and minutes. When I change the phone's timezone to MST, the notification will not fire at 9:00 AM MST and instead will fire at 10:00 AM MST (which is 9am PST). Afaik, there is no way to schedule a local notification to always fire at 9:00 AM regardless of timezone without extra coding to detect a timezone change and update the scheduled local notifications.