/// <summary>
/// Checks whether the given timeline object's attribute is editable for the current
/// context and document</summary>
/// <param name="item">Timeline object that changed</param>
/// <param name="attribute">Attribute on the timeline object that changed</param>
/// <returns>True iff this timeline object attribute is editable for the current
/// ActiveControl, ActiveContext, and ActiveDocument properties</returns>
public virtual bool IsEditable(ITimelineObject item, AttributeInfo attribute)
{
if (attribute == Schema.groupType.expandedAttribute)
{
return(true);
}
TimelinePath path = new TimelinePath(item);
return(ActiveControl.IsEditable(path));
}