// Take the result of the parent and generate the result for the next operation
internal INTERNAL_CollectionViewGroupInternal(ICollection <object> source, INTERNAL_CollectionViewGroupInternal parent, INTERNAL_Operations operations, int level = 0)
{
Items = source;
_level = level;
_parentView = parent;
_operations = operations;
object operationToDo = _operations.HandleNextOperation(_level);
ExecuteOperation(operationToDo);
}
// create all the operation tree with a new source
void CreateTree()
{
_views.Clear();
_operations = new INTERNAL_Operations(this); // we reset the operations to do
ICollection <object> newCollection = new Collection <object>();
foreach (object obj in _originalDataSource)
{
newCollection.Add(obj);
}
CollectionViewGroupInternal treeRoot = new CollectionViewGroupInternal(newCollection.ToList <object>(), null, _operations);
_views.Add(treeRoot); // we make sure that the treeRoot is the last element to be added to the _views collection because the call to the CollectionViewGroupInternal contructor creates a tree via recursion, which by itself adds the branches in _views.
ConstrainIndexToRemainInsideAllowedRange(); // because some leaves can disappear if it's not the first generation (ie. if it has already been refreshed once)
}