Z-Index | Organise Int Array - Sequence

Hello,

I can't get my head around on how to do this. I have a List that stores the value of a Z-Index of my dynamic objects, which are from 0 to Infinity.

0 being the bottom. Infinity being the top. It's infinity because the user can 'Instantiate' any number of these objects. For example, the user has initiated 5 objects, the List would look something like this:

• Object A = 0 [Bottom]

• Object B = 1

• Object C = 2

• Object D = 3

• Object E = 4 [Top]

The user has the ability to click/tap on any of these objects. With this, I would like the Z-index list to reorganise itself so the most recent tapped object is on the highest. For example, user taps Object D, List needs to look like this:

• Object A = 0 [Bottom]

• Object B = 1

• Object C = 2

• Object D = 4 [Top]

• Object E = 3

Then taps on Object A:

• Object A = 4 [Top]

• Object B = 0 [Bottom]

• Object C = 1

• Object D = 3

• Object E = 2

I just can't get my head around on how to even implement this...? Also note - the Z-Index has nothing to do with the actual transform.position.z. It's just a sequence of int numbers from 0 to the number of Initiated objects.

 var objectsList : List.<GameObject>;
 var objectsDepth : List.<int>;
 
 //this is called when the user is initiating a new object
 function UserInitatedObject(){
 
     var obj = Instantiate(object);
     objectsList.Add(obj);
 
     //make the newest object the highest depth value
     objectsDepth.Add(objectsDepth.Count);
 
 }
 
 
 //this is called when user has tapped on object within scene
 function UserTappedOnObject(index : int, object : GameObject){
 
     //need to reorganise 'objectsDepth' list so that this object is now the highest
 }