因為遊戲需要增加幾種不同的啟動模式，想在編輯器頂部Toolbar處增加幾個按鈕。

由於Unity沒有直接提供介面，需要通過反射實現。看了下有一個開源庫：

https://github.com/marijnz/unity-toolbar-extender

感覺這樣有點複雜。因此我封裝了下，全都放在了一個類裡：

namespace Hont
{
    using System;
    using System.Reflection;
    using UnityEngine;
    using UnityEditor;
    using UnityEngine.UIElements;

    [InitializeOnLoad]
    
 
public static class CruToolbar
    {
        private static readonly Type kToolbarType = typeof(Editor).Assembly.GetType("UnityEditor.Toolbar");
        private static ScriptableObject sCurrentToolbar;


        static CruToolbar()
        {
            EditorApplication.update -= OnUpdate;
            EditorApplication.update 
 
+= OnUpdate;
        }

        private static void OnUpdate()
        {
            if (sCurrentToolbar == null)
            {
                UnityEngine.Object[] toolbars = Resources.FindObjectsOfTypeAll(kToolbarType);
                sCurrentToolbar = toolbars.Length > 0 ? (ScriptableObject)toolbars[0
 
] : null;
                if (sCurrentToolbar != null)
                {
                    FieldInfo root = sCurrentToolbar.GetType().GetField("m_Root", BindingFlags.NonPublic | BindingFlags.Instance);
                    VisualElement concreteRoot = root.GetValue(sCurrentToolbar) as VisualElement;

                    VisualElement toolbarZone = concreteRoot.Q("ToolbarZoneRightAlign");
                    VisualElement parent = new VisualElement()
                    {
                        style = {
                                flexGrow = 1,
                                flexDirection = FlexDirection.Row,
                            }
                    };
                    IMGUIContainer container = new IMGUIContainer();
                    container.onGUIHandler += OnGuiBody;
                    parent.Add(container);
                    toolbarZone.Add(parent);
                }
            }
        }

        private static void OnGuiBody()
        {
            //自定義按鈕加在此處
            GUILayout.BeginHorizontal();
            if (GUILayout.Button("Full setup"))
            {
                Debug.Log("Full setup");
            }
            if (GUILayout.Button("Wramup setup"))
            {
                Debug.Log("Wramup setup");
            }
            GUILayout.EndHorizontal();
        }
    }
}

效果：