Applying The Recurrence Pattern
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Some user events are recurring – they occur repeatedly (on a regular basis). The following elements define how the recurrence is applied to the recurring user event:
The base element that defines the recurrence’s behavior is frequency – the time base used to calculate when the user event repeats – daily, weekly, monthly, or yearly (see the TcxSchedulerCustomRecurrenceInfo.Recurrence property).
The next element is the interval which defines how the recurrence’s frequency is applied: every day, every 2nd…28/29/30th/31st day, every week, every 2nd…53rd/54th week, every month, every nth month, every year, or every nth year. This element corresponds to the TcxSchedulerCustomRecurrenceInfo.Periodicity property for a frequency basis of days, weeks and months, to the TcxSchedulerCustomRecurrenceInfo.OccurDays property for specific days in a week for a frequency basis of a week, to the TcxSchedulerCustomRecurrenceInfo.DayNumber property for specific day for monthly frequency basis, and to the TcxSchedulerCustomRecurrenceInfo.YearPeriodicity for yearly frequency intervals.
Both of these elements compose the so-called Recurrence pattern, which defines when the user event reoccurs.
The Range of recurrence element defines the time boundaries/limits of a recurrence. Refer to the following usage scenarios for this element:
The Range of recurrence is represented by the start and end time of the recurrence (the TcxSchedulerCustomRecurrenceInfo.Start and TcxSchedulerCustomRecurrenceInfo.Finish properties). This type of range is applied if the value of the TcxSchedulerCustomRecurrenceInfo.Count property is 0.
The Range of recurrence is represented by the number of occurrences that should elapse until the recurrence is no longer in effect. The TcxSchedulerCustomRecurrenceInfo.Count property specifies the number of occurrences if its value is greater than 0.
The Range of recurrence is unbound if the value of the TcxSchedulerCustomRecurrenceInfo.Count property is -1.
The following example applies Recurrence pattern and Range of recurrence patterns to create a recurring user event:
// ...
with DBStorage.CreateEvent do
begin
ResourceID := 1; // assign the newly created user event to the Lesli Gritts resource. For how to set up a resource in bound mode see the Bound Mode topic
Caption := 'Appointment with a doctor'; // specify the subject
Start := Date + 10 * HourToTime; // the start time of the user event (the HourToTime constant is defined in the cxSchedulerUtils unit)
Duration := 30 * MinuteToTime; // the duration of the user event (the MinuteToTime constant is defined in the cxSchedulerUtils unit)
State := tlsOutOfOffice; // the availability status is "out of office"
EventType := etPattern; // start the series of the occurrences
RecurrenceInfo.Count := 3; // end after three occurrences
RecurrenceInfo.Recurrence := cxreDaily; // the daily basis
RecurrenceInfo.DayType := cxdtWeekDay;
RecurrenceInfo.Periodicity := 1; // repeat every weekday
Post; // synchronize with storage
end;
This is the code execution result:
Note
the output shown is produced when the scheduler’s LookAndFeel.NativeStyle property is set to False, the lfFlat flag on the LookAndFeel.Kind property is active, two resources are defined and the scheduler’s OptionsView.GroupingKind property is set to gkByDate.