WPF Toolkit Bar Chart: How to Get Inserted Items To Show Up at Inserted Position (within Chart)

Sep 12, 2013 at 4:12 PM
I am using the bar chart binding to an observable collection.
The items in the collection are
public ObservableCollection<KeyValuePair<string, double>> StarBrightnessValueList { get; set; }
To insert items in the correct position within the observable collection, I am using
                    this.MainViewModel.StarBrightnessValueList.Insert(insertIndex, new KeyValuePair<string, double>(position.ToString(), starMaxBrightness));
I though am not seeing it show up in the expected position within the bar chart. Instead it is appearing always at the end (as if it were added versus inserted). I checked and it appears to be in the correct location within the list after being inserted.

Side note: I could have added items of type KeyValuePair<double, double> but the bars directly overlap (versus being offset) if added/inserted items fall on the same x-axis value.

Thanks for any help/pointers you can lend in this.