I'm getting below exception when I move mouse on UltraWeekView's Appoinments. Could you tell me when this could happen?
System.NullReferenceException: Object reference not set to an instance of an object.
at Infragistics.Win.UltraWinSchedule.UltraScheduleControlBase.GetAppointmentToolTipText(Appointment appointment, Boolean includeTimeRange)
at Infragistics.Win.UltraWinSchedule.MonthViewSingle.SingleDayAppointmentSubjectUIElement.OnMouseEnter()
at Infragistics.Win.ControlUIElementBase.ElementEntered(UIElement element, Boolean triggerMouseLeavesOnly)
at Infragistics.Win.ControlUIElementBase.ProcessMouseMoveHelper(Object sender, MouseEventArgs e)
at Infragistics.Win.ControlUIElementBase.ProcessMouseMove(Object sender, MouseEventArgs e)
at Infragistics.Win.Utilities.ProcessEvent(Control control, ProcessEvent eventToProcess, EventArgs e)
at Infragistics.Win.UltraControlBase.OnMouseMove(MouseEventArgs e)
at System.Windows.Forms.Control.WmMouseMove(Message& m)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
Given the amount of detail provided here, the only situation I can think of that might cause this is when you have explicitly set the appointment's Description to null. You can verify whether this is causing the problem by setting it to string.Empty and see if that prevents the exception. If that works, you might want to report this as a bug since we should not be returning null from string properties.