Evaluate RecurrenceRule with modified instances

[Anonymous]

I created a recurring event and changed the time of some instances. Using the DateIterator from the RecurrenceRule gives me the dates of the event ignoring the instances I changed. What I want is to get all actual dates of the event, meaning the original one where there isn't a modified instance and the modified instance where there is one. Is there a nice way to do that in biweekly?

[Michael Angstadt]

Hello,

Can you elaborate on how you changed the time of some instances? Can you provide a code sample?

Thank you,
Mike

[Anonymous]

Hi Mike,
I used the google calendar and manually changed the time of some instances, then imported the iCal file. In an automatic way I would create a new VEvent, set the recurrenceId to the date I want to change, and then set a new start and end for the event.

The following code seems to work for my example iCal-file. It works by iterating over the recurrenceRule, excluding all the dates where the iCal contains an event with a matching recurrenceId:

HashSet<ICalDate> datesWithModifiedInstances = createDateSetFromRecurrenceIds(events);
        for (VEvent event : events) {
            RecurrenceRule recurrenceRule = event.getRecurrenceRule();
            if (recurrenceRule == null) {
                if (!event.getDateStart().getValue().before(lowerBound)) {
                    // FOUND A DATE
                }
            } else {
                DateIterator dateIterator = recurrenceRule.getDateIterator(event.getDateStart().getValue());
                Date currentDate = lowerBound;
                dateIterator.advanceTo(currentDate);
                while (dateIterator.hasNext()) {
                    currentDate = dateIterator.next();
                    if (datesWithModifiedInstances.contains(new ICalDate(currentDate))) {
                        // exclude all modified recurrence instances
                        continue;
                    }
                    if (beginsAfterUpperBound(upperBound, currentDate)) {
                        break;
                    }
                    // FOUND A DATE
                }
            }
        }

[Michael Angstadt]

Thank you for the update. Good to hear that you figured it out. Please let me know if you have any other questions.