List of List or Array of Lists for easy drag-and-drop in Inspector panel

Unity Engine
1

So I’m building my own simple script to handle sprite animations. I’m basing it off of redditor mikembley’s code here which is fundamentally quite simple.

There’s one modification that I’d like to make - that current bit of code can only handle one “animation” at a time. I have modified it to allow for a List<List>, so I can thus have a single Animator that holds every single animation that that object needs - each animation being a single List.

The problem is that declaring public List<List> animation_list; does not result in a slot appearing in the inspector panel for me to drag-and-drop anything into. If I declare just List, then I get something to appear, and I can just drag a batch of sprites over and it fills in nicely. But apparently the Inspector panel can’t handle of List of Lists.
Does anyone have a way to remedy this, or a way around it?

2

It will work if you make a custom class that’s set to System.Serializable. I did this for SpriteTile, where I have, for example:

[System.Serializable]
public class ColliderPath {
	public Vector2[] path;
	
	public ColliderPath (Vector2[] path) {
		this.path = path;
	}
}

for being able to have List<Vector2[ ]> in the inspector, by using List instead. The same principle would apply to having List<List> (which I also did, with some modifications; it’s actually more like List<List<List>>). It seems rather unnecessary to be forced to do this since Unity is obviously coded to handle nested arrays in the inspector, but it works fine.

–Eric

3

Just occured to me, since I actually never tried that before… Unity doesn’t support serialization of nested list. (List<List>)

Maybe you know… What’s actually supported in its serialization?

    public int[] arrayInt = new int[0]; // Work
    public int[,] doubleArrayInt = new int[0,0]; // Inspector doesn't show it (Serialization?)
    public int[][] nestedArrayInt = new int[0][]; // Inspector doesn't show it (Serialization?)
    public List<int> listInt = new List<int>(); // Work
    public List<List<int>> listListInt = new List<List<int>>(); // Doesn't work (no Serialization)
    public List<int[]> listArrayInt = new List<int[]>(); // Doesn't work (no Serialization)
    public List<int>[] arrayListInt = new List<int>[0]; // Inspector doesn't show it (Serialization?)
4

-[quote=“LightStriker_1, post:3, topic: 523789, username:LightStriker_1”]
Just occured to me, since I actually never tried that before… Unity doesn’t support serialization of nested list. (List<List>)

Maybe you know… What’s actually supported in its serialization?
[/quote]

See here for the documentation, though it’s fairly old and not explicit about nested lists:

http://docs.unity3d.com/Documentation/ScriptReference/SerializeField.html

5

Thanks for the responses guys! I wound up going with this:

using System;
using System.Collections.Generic;
using UnityEngine;

[Serializable]
public class SpriteList // helper class to ensure we can edit the nested lists inside the unity editor
{
public string animName;
public bool looping = true;
public bool nonLoopingDone = false;
public List Frames;
}

[RequireComponent(typeof(SpriteRenderer))]
public class AnimationDriver : MonoBehaviour
{
public List Animations;

public float timeBetweenFrames = (1/30);
public float speed = 1;

public int currentAnim = 0;
public int currentFrame = 0;
public bool animEnding = false;
private float _timer;

private SpriteRenderer _spriteRenderer;

void Start()
{
_spriteRenderer = GetComponent(); // ensure we get the component once, not every frame
}

void Update()
{
if (speed > 0) {
_timer += Time.deltaTime; // deltaTime tells time between update calls.

if (_timer >= timeBetweenFrames)
{
_timer -= timeBetweenFrames; // timer won’t be EXACT, take away playSpeed to ensure no “skipped frames” over time.

if (currentFrame++ == Animations[currentAnim].Frames.Count - 1) {
if (Animations[currentAnim].looping) {
currentFrame = 0;
} else {
currentFrame = Animations[currentAnim].Frames.Count - 1;
Animations[currentAnim].nonLoopingDone = true;
}
animEnding = true;
}

_spriteRenderer.sprite = Animations[currentAnim].Frames[currentFrame];
}
}
}
}

It works great