Basic UIList

InferSize.cs

using UnityEngine;
using System.Collections;
using UnityEngine.UI;

namespace Rubycone.BoltAction {
    [ExecuteInEditMode]
    [RequireComponent(typeof(LayoutElement))]
    public class InferSize : MonoBehaviour {

        public Graphic targetGraphic;
        public Vector2 minSizeOffset, preferredSizeOffset, flexibleSizeOffset;

        LayoutElement layout;

        protected override void OnAwake() {
            layout = GetComponent<LayoutElement>();
            if(GetComponent<Button>() != null) {
                targetGraphic = GetComponentInChildren<Text>();
                preferredSizeOffset.x = 30;
            }
        }

        protected override void OnUpdate() {
            if(targetGraphic != null) {
                layout.minWidth = LayoutUtility.GetMinWidth(targetGraphic.rectTransform) + minSizeOffset.x;
                layout.minHeight = LayoutUtility.GetMinHeight(targetGraphic.rectTransform) + minSizeOffset.y;
                layout.preferredWidth = LayoutUtility.GetPreferredWidth(targetGraphic.rectTransform) + preferredSizeOffset.x;
                layout.preferredHeight = LayoutUtility.GetPreferredHeight(targetGraphic.rectTransform) + preferredSizeOffset.y;
                layout.flexibleWidth = LayoutUtility.GetFlexibleWidth(targetGraphic.rectTransform) + flexibleSizeOffset.x;
                layout.flexibleHeight = LayoutUtility.GetFlexibleHeight(targetGraphic.rectTransform) + flexibleSizeOffset.y;
            }
        }
    }
}

UIList.cs

using UnityEngine;
using System.Collections;
using Rubycone.BoltAction;
using System.Collections.Generic;
using UnityEngine.UI;

namespace Rubycone.UI {
    [ExecuteInEditMode]
    [RequireComponent(typeof(VerticalLayoutGroup))]
    public class UIList : MonoBehaviour {
        [SerializeField, Header("Settings")]
        int fontSize;
        [SerializeField]
        FontStyle fontStyle;
        [SerializeField]
        float top, left, right, bottom;
        [SerializeField]
        Color backgroundColor, alternateColor;
        [SerializeField]
        bool alternateColors;

        [Header("Items")]
        public List<string> elements = new List<string>();

        List<ListItem> cells = new List<ListItem>();


        protected override void OnUpdate() {
            if(elements.Count != cells.Count) {
                RefreshList();
            }
            for(int i = 0; i < elements.Count; i++) {
                var li = cells[i];
                li.text.text = elements[i];
                li.text.fontSize = fontSize;
                li.text.fontStyle = fontStyle;
                li.background.color = (alternateColors && i % 2 != 0) ? alternateColor : backgroundColor;
                li.rt.anchorMin = Vector2.zero;
                li.rt.anchorMax = Vector2.one;
                li.rt.offsetMax = new Vector2(right, top);
                li.rt.offsetMin = new Vector2(left, bottom);
            }
        }

        private void RefreshList() {
            while(elements.Count > cells.Count) {
                cells.Add(CreateListItem());
            }
            while(elements.Count < cells.Count) {
                DestroyLastListItem();
            }
        }

        private void DestroyLastListItem() {
            var last = cells[cells.Count - 1];
            cells.RemoveAt(cells.Count - 1);
            if(Application.isPlaying) {
                Destroy(last.gameObj);
            }
            else {
                DestroyImmediate(last.gameObj);
            }
        }

        private ListItem CreateListItem() {
            var newChild = new GameObject("ListItem");
            var newText = new GameObject("ListItemText");

            //Set parents and scale
            newText.transform.parent = newChild.transform;
            newChild.transform.parent = transform;
            ResetTransform(newText.transform);
            ResetTransform(newChild.transform);

            var textRect = newText.AddComponent<RectTransform>();

            //Create necessary components
            var background = newChild.AddComponent<Image>();
            var text = newText.AddComponent<Text>();
            var selectable = newText.AddComponent<Selectable>();
            var inferrer = newChild.AddComponent<InferSize>();

            selectable.targetGraphic = text;
            inferrer.targetGraphic = text;
            return new ListItem(newChild, text, textRect, background);
        }

        private void ResetTransform(Transform t) {
            t.localPosition = Vector3.zero;
            t.localRotation = Quaternion.identity;
            t.localScale = Vector3.one;
        }

        public struct ListItem {
            public GameObject gameObj;
            public Text text;
            public RectTransform rt;
            public Image background;

            public ListItem(GameObject gameObj, Text text, RectTransform rt, Image background) {
                this.gameObj = gameObj;
                this.text = text;
                this.rt = rt;
                this.background = background;
            }
        }
    }
}

Both files required in project. UIList creates the actual list, while InferSize basically is a LayoutElement that uses another component to resize this one. This was created for Buttons in Layout Groups, as the button's background would get used for sizing, which having a preferred size of 0 would cause the button to be smushed. Adding the InferSize script causes the Button's Image graphic to use the Text component underneath to configure its Preferred sizes.