Yii Nested Set (Yiiext). Trying to move a root node - yii

Question

I am using the fantastic extension by Yiiext "nested-set-behavior":
https://github.com/yiiext/nested-set-behavior
I am interested to know if anyone can let me know how to move (up or down) a root node when I am running the nested set with multiple roots.
tree example:
Phones (root node)
1.1 Mobile
1.2 Fixed
Cars (root node)
2.1 Fast
2.2 Slow
2.3 Average
Planes (root node)
3.1 Large
3.2 Small
At the moment when I pull out the full tree and show this to the user I get the above result.
I would like to be able to move "Cars" before "Phones".
Is there any way of doing this?
I have tried:
$cars = Category::model()->findByPk($cars_id);
$phones = $cars->prev()->find();
$cars->moveBefore($phones);
This gives me an error in the moveAfter method of the nested set behavior class.
Any one done this before?
Thanks
Dave

Answer 1

As the doc suggest the the prev() method returns :
Array of Active Record objects corresponding to ....
Therefore you have to approach this with different way e.g
$phones = Category::model()->findByPk($phones_id);
$cars = Category::model()->findByPk($cars_id);
$cars->moveBefore($phones);
Or other approach which suits your application scenario
Your code could be fixed by :
$cars = Category::model()->findByPk($cars_id);
$phones = $cars->prev()->find();
foreach($phones as $phone){
$cars->moveBefore($phone);
}
which does not make sense ;)
(p.s: did not test this code)

Answer 2

As I understand, you have 3 nodes, which are the roots.
The problem is that the methods moveAfter() and moveBefore() can not be applied to the main roots. You are trying to move a node, relatively another node, but they are in different trees.
If cars and phones have a common root, it will be success.
In other words, you operate with nodes in different trees, which know nothing about each other.