In cases when we have loadOnDemand set to true and we want to populate the value of the DropDownTree initially we need a way to check if this value is part of the available options. One possible solution is adding a valueMapper function similar to the one use in virtualization scenarios.

Set an indicator same way that grid already does but now in sheet cells when a record is 'dirty'.

I would like to use drag and drop on treeList to reorder rows (with same parent) like on treeView or at least to have same events (drag, dragstart, dragend, drop), where I'll be able to change behaviour.