Reordering items in ListEditor

I'm editing List of ValueProxies and I'm trying to implement reordering of items (move to front, move to back, move up, move down the list). Since ListEditors work by reflecting change in underlying List and List interface does not support atomic "move" operation for item reordering, my only option is to first remove item from List and then add elements at desired index. So far so good, but in ListEditor, underlying List contains unflushed values so when I reinsert them, newely created editors get old values and I loose changes made before reordering took place.

Since flushing ListEditor before remove/add didn't seem as a good idea (breaks editor contract and I would have to propagate Driver down the editors hierarchy) I've ended up cloning ListEditor and its underlying ListEditorWrapper to my own DynamicListEditor and DynamicListEditorWrapper (couldn't even extend them, because relevant members are private).

In DynamicListEditorWrapper I've added one additional method to reorder both elements in underlying list and their corresponding editors in-place:

public void move(int fromIndex, int toIndex) {

workingCopy.add(toIndex, workingCopy.remove(fromIndex));

editors.add(toIndex, editors.remove(fromIndex));

for (int i = Math.min(fromIndex, toIndex), j = Math.max(fromIndex, toIndex); i <= j; i++)

editorSource.setIndex(editors.get(i), i);

}

In DynamicListEditor I've used that new wrapper and exposed it in getList method:

public DynamicListEditorWrapper<T, E> getList() {

return list;

}

Now I'm able to move item one place up the list by calling:

int currIndex = /* get current index, easy */;

if (currIndex == 0)

return;

listEditor.getList().move(currIndex, currIndex - 1);

I works, but I can't shake off the feeling that I'm over-engineering it and that there is a better (simpler) way for doing this. After all, Lists are ordered collections and editing that order should not be this complicated.

Any advice?

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