1 to N relationship in inspector

Questions & Answers
1

I need to map a 1 to N relationship and was trying to make a good interface for it in the inspector, but I havn’t been able to get the serialization to work correctly. It seems that Unity doesn’t want to serialize a List<List> type nor a List<Object> type. Am I thinking correctly that Unity can’t do that or is there some method I am missing?

Here’s what I have:

The class itself:

[System.Serializable]
public class GivePrize : MonoBehaviour {
	[HideInInspector]
	public List<GameObject> pre;
	[HideInInspector]
	public List<GameObject[]> result;
	[HideInInspector]
	public List<int> counts;
	[HideInInspector]
	public int prereqLength;

The editor for the class:

[CustomEditor(typeof(GivePrize))]
public class GivePrizeEditor : Editor {
	public GivePrize myObj;

	public void Awake() {
		myObj = (GivePrize) target;
	}

	public override void OnInspectorGUI() {
		base.OnInspectorGUI();

		if (myObj.pre == null) {
			myObj.pre = new List<GameObject>();
		}

		if (myObj.result == null) {
			myObj.result = new List<GameObject[]>();
		}

		if (myObj.counts == null) {
			myObj.counts = new List<int>();
		}

		myObj.prereqLength = EditorGUILayout.IntField(myObj.prereqLength);

		if (GUI.changed) {
			while (myObj.pre.Count < myObj.prereqLength) 
				myObj.pre.Add(null);

			while (myObj.result.Count < myObj.prereqLength)
				myObj.result.Add(new GameObject[1]);

			while (myObj.counts.Count < myObj.prereqLength)
				myObj.counts.Add(1);

			while (myObj.pre.Count > myObj.prereqLength)
				myObj.pre.RemoveAt(myObj.pre.Count-1);

			while (myObj.result.Count > myObj.prereqLength)
				myObj.result.RemoveAt(myObj.result.Count-1);

			while (myObj.counts.Count > myObj.prereqLength)
				myObj.counts.RemoveAt(myObj.counts.Count-1);
		}

		for (int i = 0; i < myObj.pre.Count; i++) {
			EditorGUILayout.LabelField("Prereq:");
			myObj.pre _= (GameObject)EditorGUILayout.ObjectField((GameObject)myObj.pre*, typeof(UnityEngine.GameObject), true);*_

* EditorGUILayout.LabelField(“Results:”);*
myObj.counts = EditorGUILayout.IntField(myObj.counts*);*

_ GameObject temp = myObj.result*;*_

* if (GUI.changed) {*
_ if (temp.Length < (int)myObj.counts*) {
GameObject[] newArray = new GameObject[(int)myObj.counts];*_

* for (int j = 0; j < temp.Length; j++)*
* newArray[j] = temp[j];*

_ for (int j = temp.Length; j < (int)myObj.counts*; j++)
newArray[j] = null;*_

* temp = newArray;*
_ } else if (temp.Length > (int)myObj.counts*) {
GameObject[] newArray = new GameObject[(int)myObj.counts];*_

_ for (int j = 0; j < (int)myObj.counts*; j++)
newArray[j] = temp[j];*_

* temp = newArray;*
* }*
* }*

* for (int j = 0; j < temp.Length; j++) {*
* temp[j] = (GameObject)EditorGUILayout.ObjectField((GameObject)temp[j], typeof(UnityEngine.GameObject), true);*
* }*

_ myObj.result = temp;
* }*_

* if (GUI.changed) {*
* EditorUtility.SetDirty(myObj);*
* }*
* }*
Any help would be appreciated, thanks.

2

I’ve run a quick test in a simple MonoBehaviour, and Unity does not seem to serialize nested lists or list of arrays out of the box. At least, it does not expose them in the editor.

I know this is not an answer, but if you want to avoid headaches with Unity’s serialization, I strongly recommend looking into Jacob Dufault’s Full Inspector on the Asset store. It offers a lot more than what Unity does and it’s easy to use.

I’ve tested nested lists and lists of arrays with FullInspector and they are serailized just like you’d think they’re supposed to be.