Question Changing all parents to another in editor script not working

Hi boys!

I have created a very simple editor script to change all childs inside a gameobject to a common parent but I can't understand what is wrong in the code.

I'm using Unity 2019.4.11f1

My original gameObject structure is this one



My final result is always like this:



My desired results needs to be like this:




The code:

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4. using UnityEditor;
5.  
6. public class SpecialFunctions : MonoBehaviour
7. {
8.     /////////////////////////////////////////////////////////////////////////////////
9.     /// <summary>
10.     /// ChangeAllParents
11.     /// </summary>
12.     /////////////////////////////////////////////////////////////////////////////////
13.     [MenuItem("New transform Tools/Change All Parents")]
14.     public static void ChangeAllParents()
15.     {
16.         // find base go
17.         GameObject baseGo = GameObject.Find("SpecialTest");
18.  
19.         // create temporal go
20.         GameObject temporalGo = new GameObject("TEMPORAL_" + baseGo.name);
21.  
22.         Transform baseGoTransform = baseGo.transform;
23.         Transform temporalGoTransform = temporalGo.transform;
24.  
25.         ChangeAllChildsParentsRecursivelly(baseGoTransform, temporalGoTransform);
26.     }
27.  
28.     /////////////////////////////////////////////////////////////////////////////////
29.     /// <summary>
30.     /// ChangeAllChildsParentsRecursivelly
31.     /// @param _transform
32.     /// @param _temporalGoTransform
33.     /// </summary>
34.     /////////////////////////////////////////////////////////////////////////////////
35.     private static void ChangeAllChildsParentsRecursivelly(Transform _baseTransform, Transform _temporalGoTransform)
36.     {
37.         if (_baseTransform)
38.         {
39.             _baseTransform.SetParent(_temporalGoTransform, true);
40.  
41.             Debug.Log("Separating: " + _baseTransform.name + " -> new parent name: " + _baseTransform.parent.name);
42.         }
43.         else
44.         {
45.             Debug.Log("ERROR -> _baseTransform is null: " + _baseTransform.name);
46.         }
47.  
48.         Debug.Log(_baseTransform.name + " -> childCount: " + _baseTransform.childCount);
49.  
50.         for (int i = 0; i < _baseTransform.childCount; i++)
51.         {
52.             Transform child = _baseTransform.GetChild(i);
53.  
54.             Debug.Log("Continue with child called: " + child.name);
55.  
56.             SpecialFunctions.ChangeAllChildsParentsRecursivelly(child, _temporalGoTransform);
57.         }
58.     }
59. }
60.  

Console output shows that the recursive function is not entering all childs, I can't understand why.




After hours I'm getting crazy, so any help will be very appreciated!

 

You're changing the number of children the transforms have while trying to iterate over the children!

Much simpler method to do this:

Code (CSharp):

1. Transform[] allChildren = baseGoTransform.GetComponentsInChildren<Transform>();
2.  
3. foreach (Transform t in allChildren) {
4.   t.SetParent(_temporalGoTransform);
5. }

 

Thanks @PraetorBlue !!

Anyway, i can't understand why is he original code not working even if i was changing the parent in the end). If is the parent which is changing, not the childs, why is the child count chaning?

 

On line 50, you are doing a for loop over the children of an object. Inside the loop you change the parent of the children (in the recursive function call). So let's say there are two children. You start with i = 0 and get the 0th child. You change its parent. Now there is only one child left. i++ makes i = 1. There is only one child now so childCount returns 1 and i is 1. i is not less than 1, so the loop ends, leaving a child unvisited.