using UnityEngine;

public class ClipListAttribute : PropertyAttribute
{
}

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using UnityEngine;
using UnityEditor;
using System.Reflection;
using System.Collections.Generic;

[CustomEditor(typeof(AudioManager))]
public class AudioManagerEditor : Editor
{
    private bool showClips = true;

    public override void OnInspectorGUI()
    {
        AudioManager am = (AudioManager)target;

        DrawDefaultInspector();

        GUILayout.Space(10);

        showClips = EditorGUILayout.Foldout(showClips, "Audio Clips");

        if (showClips)
        {
            FieldInfo[] fields = typeof(AudioManager).GetFields(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance);
            List<AudioClip> clips = new List<AudioClip>();

            foreach (var field in fields)
            {
                if (field.FieldType == typeof(AudioClip) &&
                    field.GetCustomAttribute(typeof(ClipListAttribute)) != null)
                {
                    AudioClip current = (AudioClip)field.GetValue(am);

                    AudioClip newClip = (AudioClip)EditorGUILayout.ObjectField(field.Name, current, typeof(AudioClip), false);

                    if (newClip != current)
                    {
                        Undo.RecordObject(am, "Modify AudioClip");
                        field.SetValue(am, newClip);
                        EditorUtility.SetDirty(am);
                    }

                    clips.Add(newClip);
                }
            }
        }
    }
}