简介

在编辑EditorWindow的时候，某些情况下，我们希望打开的窗口相对于Unity编辑器来说居中显示，一般情况下通过new Rect(0, 0, Screen.currentResolution.width, Screen.currentResolution.height)获得的是主显示器窗口的尺寸，但是如果Unity窗口非全屏或者使用多个显示器做开发，则无法得到正确的位置。

本文将介绍一种通过反射方式可以得到Unity主窗口位置信息的方法，同时也会提供对应的扩展实现以简化将EditorWindow居中显示

声明

本文中的内容属于个人总结整理而来,个人水平有限，对于部分细节难免有理解错误及遗漏之处，如果您在阅读过程中有所发现，希望您能指正，同时文章中的部分内容也参考了其它大神的文章，如果文章中的内容侵犯了您的权益，表示非常歉意，请您指出，我将尽快修改。

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Unity技术 EditorWindow居中显示实现/获取Unity主窗口的区域信息(http://www.liyubin.com/articles/2020/11/16/1605527665480.html)

获取Unity主窗口所在的区域信息

1. 通过反射的方式获取需要的指定类型的所有的子类。

   public static class ReflectionUtility
   {
       public static Type[] GetAllChildClasses(Type baseType, bool allowInvisible = false, bool allowAbstract = false)
       {
           var types = new List<Type>();
           var assemblies = AppDomain.CurrentDomain.GetAssemblies();
           var isSubclass = baseType.IsGenericType
               ? (Func<Type, bool>)
                   ((type) => IsSubclassOfRawGeneric(type,baseType))
               : ((type) => type.IsSubclassOf(baseType));
   
           foreach (var assembly in assemblies)
           {
               foreach (var type in assembly.GetTypes())
               {
                   if (!isSubclass(type) ||(!type.IsVisible&&!allowInvisible) || (!allowAbstract && type.IsAbstract))
                   {
                       continue;
                   }
   
                   types.Add(type);
               }
           }
   
           return types.ToArray();
       }
   }
   

   GetAllChildClasses函数参数说明：

   • baseType:指定的基类
   • allowInvisible:是否获取隐藏的类型（比如使用private,interval修饰的类型）
   • allowAbstract:是否获取虚类型

2. 通过反射的方式获取Unity主窗口的位置信息

   public static class AppExtension
       {
           private static Rect GetEditorMainWindowPos()
           {
               var containerWinType = ReflectionUtility.GetAllChildClasses(typeof(ScriptableObject),true).Where(t => t.Name == "ContainerWindow").FirstOrDefault();
               if (containerWinType == null)
                   throw new System.MissingMemberException("Can't find internal type ContainerWindow. Maybe something has changed inside Unity");
               var showModeField = containerWinType.GetField("m_ShowMode", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);
               var positionProperty = containerWinType.GetProperty("position", System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Instance);
               if (showModeField == null || positionProperty == null)
                   throw new System.MissingFieldException("Can't find internal fields 'm_ShowMode' or 'position'. Maybe something has changed inside Unity");
               var windows = Resources.FindObjectsOfTypeAll(containerWinType);
               foreach (var win in windows)
               {
                   var showmode = (int)showModeField.GetValue(win);
                   if (showmode == 4) // main window
                   {
                       var pos = (Rect)positionProperty.GetValue(win, null);
                       return pos;
                   }
               }
               throw new System.NotSupportedException("Can't find internal main window. Maybe something has changed inside Unity");
           }
       }
   

EditorWindow窗口居中显示

我们使用扩展函数来实现窗口居中。

public static class EditorWindowExtension
{
    public static void CenterOnMainWin(this EditorWindow win)
    {
        var main = AppExtension.GetEditorMainWindowPos();
        var pos = win.position;
        float w = (main.width - pos.width) * 0.5f;
        float h = (main.height - pos.height) * 0.5f;
        pos.x = main.x + w;
        pos.y = main.y + h;
        win.position = pos;
    }
}

使用方式

public class LogViewer : EditorWindow
{
    [MenuItem("Game/Log/Viewer")]
    public static void ShowWin()
    {
        var viewer = GetWindow<LogViewer>();
        viewer.titleContent = new GUIContent("Log Viewer");
        
        viewer.CenterOnMainWin();

        viewer.Show();
    }
}

参考资料

• Editor Window - How to center a window.