UI Events: Displaying of Relative Dates
The date and time control can display relative dates—that is, values such as @Today or @WeekStart (shown below).

To specify that a user can enter relative dates in the control, you need to implement the RowSelected event handler. In the event handler, you call the PXDatetimeFieldState.showRelativeDates method to indicate that the values are allowed.
An example of such a handler is shown in the following code.
@handleEvent(CustomEventType.RowSelected, { view: "Rules" })
onEPRuleConditionSelected(
args: RowSelectedHandlerArgs<PXViewCollection<EPRuleCondition>>)
{
const ar = args.viewModel.activeRow;
ar.Value?.to(PXDatetimeFieldState).showRelativeDates();
}