WPF Timeline Exception in user control when use timeline.ResetEvents

Feb 8, 2010 at 10:01 AM


I have added the WPF Timeline to and existing project and all works well with a timeline with no events, when I add a click event to add events to the timline and and call timeline.ResetEvents I get the following exception:

Object reference not set to an instance of an object.

System.NullReferenceException was unhandled by user code
  Message=Object reference not set to an instance of an object.
       at TimelineLibrary.TimelineBand.set_TimelineEvents(List`1 value) in TimelineBand.cs:line 788
       at TimelineLibrary.TimelineTray.RefreshEvents() in TimelineTray.cs:line 283
       at TimelineLibrary.TimelineTray.ClearEvents() in TimelineTray.cs:line 253


public List<TimelineEvent> TimelineEvents
                return m_calc.TimelineEvents;
                Debug.Assert(value != null);
                m_calc.TimelineEvents = value;

Any ideas?

When I do exactly the same in the WPF sample your provided it works fine, in my existng project it fails.