前面文章里的拓展都局限在Inspector窗口中，依附于挂载MonoBehaviour脚本的游戏物体存在。下面我们将学习如何创建一个和Inspector同级的窗口，作为独立的编辑器使用。
我们假设这样一个需求：敌人都挂载一个叫“Enemy”的脚本，并在这个脚本上有一个“EnemyData”的ScriptableObjct的引用。我们需要设计一个EnemyEditor，拥有独立的窗口来编辑EnemyData，并可以创建EnemyData或在场景创建拥有EnemyData的敌人物体。
EnemyData:

using UnityEngine;
[CreateAssetMenu(fileName = "EnemyData000", menuName = "EnemyData")]
public class EnemyData : ScriptableObject
{
    public int id;
    public string enemyName;        //名称
    public Sprite portrait;         //头像
    public float maxHealth;         //血量

    public bool canAttack;          //是否可攻击
    public float attack;            //攻击力
    public float attackCoolDown;    //攻击冷却时间

    public string description;       //简介
    public string dropItems;         //掉落物名称
    public float dropRate;           //掉落概率
}

Enemy:

using UnityEngine;

public class Enemy : MonoBehaviour
{
    [SerializeField] private EnemyData data;

    public void SetData(EnemyData data)
    {
        this.data = data;
    }
}

接下来我们编写具体的窗口。Unity中的自定义窗口需要继承EditorWindow类，可以且最好放进Editor文件夹。窗口类（采用IMGUI方案）有以下两个核心方法：

OpenWindow：自定义的公共静态方法，名称随意。用于唤出窗口

OnGUI：和Start、Update等相同的生命周期函数，用于绘制自定义的GUI元素和交互逻辑
大致结构是这样的：

using UnityEngine;
using UnityEditor;
public class EnemyEditor : EditorWindow
{
    [MenuItem("Tools/EnemyEditor")]                     //将唤出按钮添加到顶部菜单栏
    public static void OpenWindow()
    {
        EnemyEditor wd = GetWindow<EnemyEditor>();       //唤出窗口
        wd.titleContent = new GUIContent("敌人编辑器");  //添加标题
    }

    private void OnGUI()
    {
        //绘制元素和交互逻辑
    }
}

上面的代码已经可以允许我们通过Unity编辑器上方菜单栏打开名为“敌人编辑器”的空窗口。而还未编辑的OnGUI是我们的老朋友，想必大家已经很清楚该如何自由发挥了。
直接上代码和效果演示

using UnityEngine;
using UnityEditor;
using System.IO;
public class EnemyEditor : EditorWindow
{
    private EnemyData editingData;                              //正在编辑的数据
    public const string DATA_PATH = "Assets/Data/EnemyData";    //储存Asset的文件夹地址

    [MenuItem("Tools/EnemyEditor")]                             //将唤出按钮添加到顶部菜单栏
    public static void OpenWindow()
    {
        EnemyEditor wd = GetWindow<EnemyEditor>();       //唤出窗口
        wd.titleContent = new GUIContent("敌人编辑器");  //添加标题
    }

    private void OnEnable()
    {
        editingData = new EnemyData();
    }

    private void OnGUI()
    {        
        GetInput();

        //两个按钮
        if (GUILayout.Button("创建EnemyData"))
        {
            CreateEnemyData();
            editingData = new EnemyData();
        }
        if (GUILayout.Button("创建敌人到场景"))
        {
            CreateEnemy();
            editingData = new EnemyData();
        }
    }
    /// <summary>
    /// 将当前编辑中的EnemyData作为Asset储存到指定路径
    /// 创建的资源根据id命名，同id资源将会被覆盖
    /// </summary>
    /// <returns>创建的资源</returns>
    private EnemyData CreateEnemyData()
    {
        if (!Directory.Exists(DATA_PATH)) Directory.CreateDirectory(DATA_PATH);
        string path = Path.Combine(DATA_PATH, "EnemyData" + string.Format("{0:D3}", editingData.id) + ".asset");
        EnemyData has = AssetDatabase.LoadAssetAtPath(path, typeof(EnemyData)) as EnemyData;
        if (has == editingData) return editingData;
        if (has != null) AssetDatabase.DeleteAsset(path);
        AssetDatabase.CreateAsset(editingData, path);        
        return editingData;
    }
    /// <summary>
    /// 将当前编辑中的EnemyData作为Asset储存到指定路径，
    /// 并在场景中添加拥有该数据的敌人对象
    /// </summary>
    /// <returns>创建的敌人对象</returns>
    private GameObject CreateEnemy()
    {
        GameObject g = new GameObject(editingData.enemyName);
        Enemy e = (Enemy)g.AddComponent(typeof(Enemy));
        e.SetData(CreateEnemyData());
        return null;
    }
    /// <summary>
    /// 创建各参数的输入框，接受输入
    /// </summary>
    private void GetInput()
    {
        SerializedObject so = new SerializedObject(editingData);
        so.UpdateIfRequiredOrScript();

        editingData.id = EditorGUILayout.IntField(new GUIContent("ID"), editingData.id);
        editingData.enemyName = EditorGUILayout.TextField(new GUIContent("名称"), editingData.enemyName);
        editingData.portrait = EditorGUILayout.ObjectField(new GUIContent("头像"),
            editingData.portrait, typeof(Sprite), false) as Sprite;
        editingData.maxHealth = EditorGUILayout.FloatField(new GUIContent("生命值"), editingData.maxHealth);
        editingData.canAttack = EditorGUILayout.Toggle(new GUIContent("是否可攻击"), editingData.canAttack);
        if (editingData.canAttack)
        {
            editingData.attack = EditorGUILayout.FloatField(new GUIContent("攻击力"), editingData.attack);
            editingData.attackCoolDown = EditorGUILayout.FloatField(new GUIContent("攻击冷却时间"),
                editingData.attackCoolDown);
        }

        editingData.dropItem = EditorGUILayout.TextField(new GUIContent("掉落物"), editingData.dropItem);
        editingData.dropRate = EditorGUILayout.Slider(new GUIContent("掉落率"), editingData.dropRate, 0, 1);

        EditorGUILayout.LabelField(new GUIContent("简介"));
        editingData.description = EditorGUILayout.TextArea(editingData.description,
            GUILayout.Height(EditorGUIUtility.singleLineHeight * 4));

        so.ApplyModifiedProperties();
    }    
}