protected internal override IEnumerable GetDetailsForParentItem(DataGridCollectionViewBase parentCollectionView, object parentItem)
{
EntityObject entityObject = parentItem as EntityObject;
if (entityObject == null)
{
return(null);
}
// Even if EntityObject is not in a loadable state, we must still return the IList
// so that the ItemProperties can be extracted based on the elements type.
bool entityObjectLoadable = ItemsSourceHelper.IsEntityObjectLoadable(entityObject);
// We let the user take charge of handling the details.
QueryEntityDetailsEventArgs args = new QueryEntityDetailsEventArgs(entityObject);
if (entityObjectLoadable)
{
this.OnQueryDetails(args);
}
// The parentItem must implement IEntityWithRelationships
Type parentItemType = parentItem.GetType();
if (typeof(IEntityWithRelationships).IsAssignableFrom(parentItemType))
{
// Since the relationship was based on the the property
// name, we must find that property using reflection.
PropertyInfo propertyInfo = parentItemType.GetProperty(this.RelationName);
if (propertyInfo != null)
{
RelatedEnd relatedEnd = propertyInfo.GetValue(parentItem, null) as RelatedEnd;
if (relatedEnd != null)
{
// Make sure that the details are loaded
// except if the user already handled it.
if (!relatedEnd.IsLoaded &&
!args.Handled &&
entityObjectLoadable)
{
relatedEnd.Load();
}
IListSource listSource = relatedEnd as IListSource;
// Returns an IList to have proper change notification events.
if (listSource != null)
{
return(listSource.GetList());
}
}
}
}
return(null);
}