[Design] Floating timezones

[Mimi Yin]

Here is the long-awaited summary of the floating timezones proposal  
put forth on the design list Jan 6th.

I wrote up a proposal for implementing a variation on how iCal treats  
timezones in the UI:
+ OOTB, Chandler calendar does not support timezones. No pulldowns to  
specify or display a timezone for the calendar canvas. No pulldowns  
to specify or display timezones for individual events.
+ Users interested in timezone support can look for it in Preferences  
and activate it explicitly.

This split off into 3 separate threads:
===
1. Should we store events as floating when timezone support has not  
been activated?

Some use cases for doing this:
+ Users who don't really travel much or don't use their calendar when  
traveling.
++ They only use calendars for work and they mostly travel for  
vacation or family holidays.

+ Users who do travel but prefer to do all the timezone math in their  
head.
++ Described David Allen's way of sorting out timezones in his calendar.
++ People get used to identifying certain meetings by their start  
time or approximate placement physically on the calendar canvas, ie.  
"that 1:30" meeting, irrespective of what timezone they're in. So  
keeping the "1:30" meeting in the 1:30 slot is important, even if the  
user changes the "clock" on their computer to a new timezone.

However, Grant pointed out that in iCal, they actually store the  
events in the "local" timezone even though the UI pretends to not  
know anything about timezones. As a result, in iCal if you change  
your "clock" on your computer to a new timezone, all of the events on  
your calendar will get moved automatically. If you go from San  
Francisco to New York, events that started at 1:30PM will show up as  
starting at 4:30PM.

There are also some complications if you pretend that timezones don't  
exist:
+ What happens when you receive an invitation for an event that is  
stored in a specific timezone?
+ What happens when you subscribe to a calendar that is stored in a  
specific timezone(s)

Some possible solutions:
+ Throw up a dialog to let people turn on timezones support AND/OR
+ The new events show up on your calendar as floating, but the  
specific timezone they're stored in is displayed, but not editable.  
So if you have NOT turned on timezone support and receive an event  
for 1-2PM EST, it will show up in the 1-2PM slot on the calendar and  
the detail view will display: 1-2PM EST.

===
2. Should we have preferences at all?

Jeffrey wasn't sure whether we wanted to hide timezones by default.
Philippe pointed out that users looking for timezone support will be  
motivated to look for it in preferences.
Brendan thought most student users of calendars wouldn't need  
timezone support but wasn't sure if that was a valid user group.

===
3. Oren brought up an import bug when importing calendars from Oracle  
calendar. This is being addressed as a bug in bugzilla. http:// 
bugzilla.osafoundation.org/show_bug.cgi?id=5000

Mimi