Drop-down Term selector for Unity I2 Localization

LocIDAttribute.cs

using UnityEngine;

/// <summary>
/// Custom attribute to display a drop-down list containing localized Terms.
/// 
/// Usage:
/// 
/// class Foo : ScriptableObject
/// {
///   [LocID]
///   string nameID;
/// }
/// 
/// </summary>
public class LocIDAttribute : PropertyAttribute
{
}

LocIDAttributeEditor.cs

using I2.Loc;
using System.Collections.Generic;
using UnityEditor;
using UnityEngine;

/// <summary>
/// Editor for LocIDAttribute.
/// </summary>
[CustomPropertyDrawer(typeof(LocIDAttribute))]
public class LocIDAttributeEditor : PropertyDrawer
{
	private string[] _termsArray = null;
	private List<string> _terms = null;

	public override void OnGUI(Rect position, SerializedProperty property, GUIContent label)
	{
		EditorGUI.BeginProperty(position, label, property);
		
		// Get term list
		if (_terms == null || _termsArray == null)
		{
			_terms = LocalizationManager.GetTermsList();
			_terms.Sort(System.StringComparer.OrdinalIgnoreCase);
			_termsArray = _terms.ToArray();
		}

		// Edit value
		position = EditorGUI.PrefixLabel(position, GUIUtility.GetControlID(FocusType.Passive), new GUIContent(property.displayName));
		var amountRect = new Rect(position.x, position.y, position.width, position.height);

		int currentIndex = _terms.IndexOf(property.stringValue);
		currentIndex = EditorGUI.Popup(amountRect, currentIndex, _termsArray);
		if (currentIndex >= 0)
		{
			property.stringValue = _termsArray[currentIndex];
		}
		
		EditorGUI.EndProperty();
	}
}