Adds an action handler to the calender that handles event produced by the context menu.
The {@link Handler#getActions(Object,Object)} parameters depend on whatview the Calendar is in:
- If the Calendar is in Day or Week View then the target parameter will be a {@link CalendarDateRange} with a range ofhalf-an-hour. The {@link Handler#getActions(Object,Object)} method willbe called once per half-hour slot.
- If the Calendar is in Month View then the target parameter will be a {@link CalendarDateRange} with a range of one day. The{@link Handler#getActions(Object,Object)} will be called once for eachday.
The Dates passed into the {@link CalendarDateRange} are in the sametimezone as the calendar is.
The {@link Handler#handleAction(Action,Object,Object)} parametersdepend on what the context menu is called upon:
- If the context menu is called upon an event then the target parameter is the event, i.e. instanceof {@link CalendarEvent}
- If the context menu is called upon an empty slot then the target is a {@link Date} representing that slot