iCalMaker – repeating events
I have just spent a couple of days exchanging e-mails with a user in the US that was having some problems with moving repeat events from iCal to a Palm using iCalMaker.
The user was able to save the iCal calendar as a file and then import it into iCalMaker with no problems (or they could have just used the ‘direct’ import from iCal method). The problem arose when they were trying to save the iCal calendar as a vcal file that could be imported in to their Palm.
This is a depressingly common problem.
What they have encountered is a lack of backward compatibility between vcal version 2 (as used by iCal) and version 1 (as used by Palm). In iCal it is possible to create certain types of repeating events that do not have an equivalent format in vcal version 1. Therefore, it is not possible can’t ‘map’ between the two.
In this case it was the dreaded ‘WKST’ problem and there is no equivalent in version 1.
As the version 2 documents say:
“The WKST rule part specifies the day on which the workweek starts. Valid values are MO, TU, WE, TH, FR, SA and SU. This is significant when a WEEKLY RRULE has an interval greater than 1, and a BYDAY rule part is specified. This is also significant when in a YEARLY RRULE when a BYWEEKNO rule part is specified. The default value is MO.”
The real problem arises when a person using iCal with a Thursday week start and a week repeating event of Mondays and Fridays. In the first week you get Fri – Mon – Fri etc in iCal., but if you ignore the week start it becomes Mon – Fri – Mon etc. (i.e. you are assuming a Sunday week start). It could be possible to work out some method/code to solve this problem but it means it is not a ‘direct map’ and this worries me, i.e. it is a lossy translation, if you went from version 2, to version 1, and back version 1 the calendar ‘text’ you end up with would not be the same as the start ‘text’. Alternatively, I could expand the repeat to single events, however, this is also lossy as it mean the connection between the events is destroyed….
As you can see. It is not an easy on to solve…..
A free trial version of iCalMaker is available – download iCalMaker
iCalMaker is an easy to use, $34.95 (USD), Mac OS X program for the rapid creation of vCal diary appointment files for use with iCal and other such applications.
