configure the visible range when in "Business hours" mode while the DayStartTime
configure the working hours in the day(i.e. the white timeslots are business hours and the grey timeslots are non-business hours).
Here is a screencast
demonstrating the timeslots appearance when the following configurations are added to the Scheduler of the PDF Export demo
DayStartTime="06:00:00" WorkDayStartTime="10:00:00" WorkDayEndTime="14:00:00" DayEndTime="21:00:00"
If that does not help, would you please send us a sample implementation of your scenario? Thus, we would be able to investigate locally and provide you more specific suggestions.
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