Default value on List vanished

Questions & Answers
1

Is there any way to pass a default value to list-elements? I mean when I edit a list in edit mode and add an element, it should initialize its value to a custom default value, not 0.

_

[System.Serializeable]
public class Test {
    int value = 500;
}

public class TestManager : MonoBehaviour {

    public Test testInt;

    public List<Test> testInts;

}

_

In the inspector, testInt.value has 500 as I wanted. But what if I want to have multiple Test Instances? Therefore I will use the list. But if I increase the size of the list,** it will have their values set to 0, not 500**.

_

I have tried to implement a constructor that should force them to serialize:

[System.Serializeable]
public class Test {
    int value = 500;

    public Test(){
        Debug.Log("Iam called but the following line not?");
        value = 500;
    }
}

and this will be called whereever I add one Test-Instance to the list as the console shows the debug.Log. However it still does not initialize the value to 500. I dont know why, I mean this is such a simple task and it only works on single fields, not with lists.

I hope you understand what I mean.

2

Ok I found a solution in case somebody has the same problem.
No need of cTor or ISerializableCallbackReceiver. This uses the Reset Callback (from the coq) that will also call at instanciation. Cheers!
_

[System.Serializeable]
public class Test {
    int value = 500;
}

public class TestManager : MonoBehaviour {
    public Test testInt;
    public List<Test> testInts;

    void Reset(){
        testInts = new List<Test>(){
            new Test()
        };
    }
}
3

For anyone looking for answer now:
I ended up creating a button in my scriptable object that when clicked assigned values to its field automatically so that I don’t have to manually.

using System.Collections.Generic;
    using UnityEngine;
    
    [CreateAssetMenu(fileName = "Item Database", menuName = "Create database/Item Database")]
    public class ItemDatabase : ScriptableObject
    {
        public List<Item> itemList;
    
        public bool Valid => itemList != null ? itemList.Count > 0 : false;
    
        public Item FetchItemByID(int id)
        {
            for (int i = 0; i < itemList.Count; i++)
            {
                if (itemList*.itemId == id)*

return itemList*;*
}
return null;
}

public void AssignIds()
{
foreach(Item item in itemList)
{
item.itemId = itemList.IndexOf(item);
}
}
}

[System.Serializable]
public class Item
{
public int itemId;
public string itemName;
public string itemDescription;
public string slug;
public bool stackable;
public string itemType;
public GameObject itemPrefab;
public Sprite itemIcon;

public Item()
{
this.itemId = -1;
}
}
----------
using System.Collections;
using System.Collections.Generic;
using UnityEditor;
using UnityEngine;

[CustomEditor(typeof(ItemDatabase))]
public class ItemDatabaseEditor : Editor
{
public override void OnInspectorGUI()
{
base.OnInspectorGUI();
var script = (ItemDatabase)target;

if(script.Valid)
{
if(GUILayout.Button(“Automatic Assign Ids”, GUILayout.Height(40)))
{
script.AssignIds();
}
}
else
{
GUIStyle style = GUI.skin.box;
style.normal.textColor = Color.yellow;
style.fixedHeight = 40;
style.stretchWidth = true;
style.alignment = TextAnchor.MiddleCenter;

GUILayout.Box(“Add Elements to the list to enable this button”, style);
}
}
}

4

What I did is this:

public class Example {
        public float value_a = 1.0f;
        public float value_b = 1.0f;
        public Example(float a, float b)
        {
            value_a  = a;
            value_b  = b;
        }
}

This gives preset properties to the array when there is nothing in the component.

public Example [] inputs = new Example [] { new Example (0.5f, 0.5f) };