// Generate sub-group based on property equality
void GroupBy(INTERNAL_PropertyGroupDescription operation)
{
List <Collection <object> > childGroups = new List <Collection <object> >();
foreach (object item in Items)
{
bool find = false;
foreach (Collection <object> child in childGroups)
{
if (Object.Equals(GetValue(child[0], operation), GetValue(item, operation)))
{
child.Add(item);
find = true;
break;
}
}
if (!find)
{
childGroups.Add(new Collection <object>());
childGroups[childGroups.Count - 1].Add(item);
}
}
foreach (Collection <object> child in childGroups)
{
INTERNAL_CollectionViewGroupInternal newView = new INTERNAL_CollectionViewGroupInternal(child, this, _operations, _level + 1);
_operations.Requester.AddView(newView); // create child branch (level matter in grouping views)
}
}
// Execute the next operation requested in the operations list
void ExecuteOperation(object operation)
{
if (operation != null)
{
IsLeaf = false;
if (operation is FilterDescription)
{
FilterDescription filterOperation = (FilterDescription)operation;
// both cannot be null and both cannot be not null
if (filterOperation.FilterUsingAnEvent != null)
{
Filter(filterOperation.FilterUsingAnEvent);
}
else
{
Filter(filterOperation.FilterUsingAPredicate);
}
}
else if (operation is PropertySortDescription)
{
PropertySortDescription sortOperation = (PropertySortDescription)operation;
if (sortOperation.Comparer == null)
{
Sort(sortOperation);
}
else
{
CustomSort(sortOperation);
}
}
else if (operation is INTERNAL_PropertyGroupDescription)
{
INTERNAL_PropertyGroupDescription groupOperation = (INTERNAL_PropertyGroupDescription)operation;
GroupBy(groupOperation);
}
else
{
throw new InvalidOperationException("unknow operation type");
}
}
else // if the operation to do on this view is null, that mean we have reach the end of the operation list and this view is usable as data source
{
IsLeaf = true;
}
}
// Get the value of the property described in operation by reflection
object GetValue(object obj, INTERNAL_PropertyGroupDescription operation)
{
return(obj.GetType().GetProperty(operation.PropertyName).GetValue(obj, null));
}