WaterFlush/Assets/AIPagedLod/Scripts/Editor/EditorMonoBehaviour.cs

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

namespace AIPagedLod
{
    [InitializeOnLoad]
    public class EditorMonoBehaviour
    {
        static EditorMonoBehaviour()
        {
            var type = System.Reflection.Assembly.Load("UnityEditor.dll").GetType("UnityEditor.EditorAssemblies");
            var method = type.GetMethod("SubclassesOf", BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Instance, null, new Type[] { typeof(Type) }, null);
            var e = method.Invoke(null, new object[] { typeof(EditorMonoBehaviour) }) as IEnumerable;
            foreach (Type editorMonoBehaviourClass in e)
            {
                method = editorMonoBehaviourClass.BaseType.GetMethod("OnEditorMonoBehaviour", BindingFlags.NonPublic | BindingFlags.Instance);
                if (method != null)
                {
                    method.Invoke(System.Activator.CreateInstance(editorMonoBehaviourClass), new object[0]);
                }
            }
        }

        private void OnEditorMonoBehaviour()
        {
            EditorApplication.update += Update;
            EditorApplication.hierarchyWindowChanged += OnHierarchyWindowChanged;
            EditorApplication.hierarchyWindowItemOnGUI += HierarchyWindowItemOnGUI;
            EditorApplication.projectWindowChanged += OnProjectWindowChanged;
            EditorApplication.projectWindowItemOnGUI += ProjectWindowItemOnGUI;
            EditorApplication.modifierKeysChanged += OnModifierKeysChanged;

            EditorApplication.CallbackFunction function = () => OnGlobalEventHandler(Event.current);
            FieldInfo info = typeof(EditorApplication).GetField("globalEventHandler", BindingFlags.Static | BindingFlags.Instance | BindingFlags.NonPublic);
            EditorApplication.CallbackFunction functions = (EditorApplication.CallbackFunction)info.GetValue(null);
            function += function;
            info.SetValue(null, (object)functions);
            EditorApplication.searchChanged += OnSearchChanged;

            Start();
        }

        public virtual void Start()
        { }

        public virtual void Update()
        { }

        public virtual void OnHierarchyWindowChanged()
        { }

        public virtual void HierarchyWindowItemOnGUI(int instanceID, Rect selectionRect)
        { }

        public virtual void OnProjectWindowChanged()
        { }

        public virtual void ProjectWindowItemOnGUI(string guid, Rect selectionRect)
        { }

        public virtual void OnModifierKeysChanged()
        { }

        public virtual void OnGlobalEventHandler(Event e)
        { }

        public virtual void OnSearchChanged()
        { }

        public virtual void OnPlaymodeStateChanged(PlayModeState playModeState)
        { }

        public enum PlayModeState
        {
            Playing,
            Paused,
            Stop,
            PlayingOrWillChangePlayMode
        }
    }
}