Unity 编辑器-UGUI拓展Button,一个和原Button一样按钮⭐

需求

想拓展一下UGUI的Button,找了几个帖子，只是能实现功能，但是用起来总有些不尽人意的地方，想办法处理一下

实现

1.创建继承自Button的类

using UnityEngine;
using UnityEngine.UI;public class CustomButton : Button
{[SerializeField] public int audioKey = -1;protected override void Start(){base.Start();onClick.AddListener(PlaySound);}private void PlaySound(){if (audioKey != -1){// AudioManager.Instance.PlaySound(audioKey);}}
}

这里只临时做一丢丢功能示例，我们预期的是上面代码中的属性在Inspector中显示出来，然而并没有

2.处理Inspector 显示问题

using UnityEditor;
[CustomEditor(typeof(CustomButton))]
public class CustomButtonEditor : UnityEditor.UI.ButtonEditor
{public override void OnInspectorGUI(){var btn = (CustomButton)target;btn.audioKey = EditorGUILayout.IntField("Audio Key", btn.audioKey);base.OnInspectorGUI();}
}

如图，属性已经能正确显示

目前只能通过AddComponent的方式创建，我们预期的是和unity 自带的Button一样的创建方式
注意：editor脚本继承自对应组件的Editor,如上面Button的，继承自 UnityEditor.UI.ButtonEditor，否则Inspector显示可能出现问题

3.处理在prafab中和hierarchy中创建按钮

• 整理一下Button的使用体验
• 1. 右键创建
• 2. 自动挂载Image,用于接收raycast
• 3. 自动挂载text显示文案
• 4. 创建节点时，需要区分是否是编辑prefab模式，是否有选中的父节点,确定生成节点的位置
• 5. 创建节点时，需要区分是否在canvas下等情况，是否需要生成canvas

using System.Collections;
using System.Collections.Generic;
using TMPro;
using UnityEditor;
using UnityEngine;
using UnityEngine.UI;public class CustomUI : Editor
{[MenuItem("GameObject/UI/CustomButton")]public static void CreateCustomButton(){//创建按钮var btn = ObjectFactory.CreateGameObject("CustomButton");ObjectFactory.AddComponent<RectTransform>(btn);var img = ObjectFactory.AddComponent<Image>(btn);img.raycastTarget = true;img.type = Image.Type.Sliced;img.sprite = AssetDatabase.GetBuiltinExtraResource<Sprite>("UI/Skin/UISprite.psd");ObjectFactory.AddComponent<CustomButton>(btn);if (!UnityEditor.SceneManagement.EditorSceneManager.IsPreviewSceneObject(btn)){//非prefab编辑模式下，需要找父节点canvasif (Selection.activeObject != null && Selection.activeObject is GameObject){var go = (GameObject)Selection.activeObject;if (go.GetComponentInParent<Canvas>(true)){btn.transform.SetParent(go.transform);}else{var canvas = CreateCanvas();canvas.transform.SetParent(go.transform);btn.transform.SetParent(canvas.transform);}}else{var canvas = FindFirstObjectByType<Canvas>();if(canvas == null){canvas = CreateCanvas();}btn.transform.SetParent(canvas.transform);}}else{//prefab编辑模式下，直接添加到选中的物体下if (Selection.activeObject != null && Selection.activeObject is GameObject){var go = (GameObject)Selection.activeObject;btn.transform.SetParent(go.transform);}}btn.GetComponent<RectTransform>().sizeDelta = new Vector2(160, 50);btn.transform.localPosition = Vector3.zero;//选中按钮节点Selection.activeObject = btn;//展开到当前节点Expend(btn.transform.parent,true);//文本var txt = ObjectFactory.CreateGameObject("Text");ObjectFactory.AddComponent<RectTransform>(txt);ObjectFactory.AddComponent<TextMeshProUGUI>(txt);txt.transform.SetParent(btn.transform);txt.transform.localPosition = Vector3.zero;txt.GetComponent<RectTransform>().sizeDelta = new Vector2(160, 50);//tmpvar tmp = txt.GetComponent<TextMeshProUGUI>();tmp.alignment = TextAlignmentOptions.Center;tmp.raycastTarget = false;tmp.text = "button";}/// <summary>/// 创建Canvas/// </summary>/// <returns>canvas</returns>private static Canvas CreateCanvas(){var canvas = ObjectFactory.CreateGameObject("Canvas");var c = ObjectFactory.AddComponent<Canvas>(canvas);c.renderMode = RenderMode.ScreenSpaceOverlay;ObjectFactory.AddComponent<CanvasScaler>(canvas);ObjectFactory.AddComponent<GraphicRaycaster>(canvas);canvas.layer = LayerMask.NameToLayer("UI");return c;}private static void Expend(Transform transform,bool expand){SceneHierarchyUtility.SetExpanded(transform.gameObject,expand);if(transform.parent != null){Expend(transform.parent,expand);}}}

添加按钮菜单如图所示

4.处理一些细节

创建后如图所示，节点正确创建了，但我们的预期是下面这样，自动选中+展开

自动选中比较简单

	Selection.activeObject = btn;

展开找了 网友的方法,很好用

using System.Collections.Generic;
using System.Reflection;
using UnityEditor;
using UnityEngine;/// <summary>
/// Editor functionalities from internal SceneHierarchyWindow and SceneHierarchy classes. 
/// For that we are using reflection.
/// </summary>
public static class SceneHierarchyUtility
{/// <summary>/// Check if the target GameObject is expanded (aka unfolded) in the Hierarchy view./// </summary>public static bool IsExpanded(GameObject go){return GetExpandedGameObjects().Contains(go);}/// <summary>/// Get a list of all GameObjects which are expanded (aka unfolded) in the Hierarchy view./// </summary>public static List<GameObject> GetExpandedGameObjects(){object sceneHierarchy = GetSceneHierarchy();MethodInfo methodInfo = sceneHierarchy.GetType().GetMethod("GetExpandedGameObjects");object result = methodInfo.Invoke(sceneHierarchy, new object[0]);return (List<GameObject>)result;}/// <summary>/// Set the target GameObject as expanded (aka unfolded) in the Hierarchy view./// </summary>public static void SetExpanded(GameObject go, bool expand){object sceneHierarchy = GetSceneHierarchy();MethodInfo methodInfo = sceneHierarchy.GetType().GetMethod("ExpandTreeViewItem", BindingFlags.NonPublic | BindingFlags.Instance);methodInfo.Invoke(sceneHierarchy, new object[] { go.GetInstanceID(), expand });}/// <summary>/// Set the target GameObject and all children as expanded (aka unfolded) in the Hierarchy view./// </summary>public static void SetExpandedRecursive(GameObject go, bool expand){object sceneHierarchy = GetSceneHierarchy();MethodInfo methodInfo = sceneHierarchy.GetType().GetMethod("SetExpandedRecursive", BindingFlags.Public | BindingFlags.Instance);methodInfo.Invoke(sceneHierarchy, new object[] { go.GetInstanceID(), expand });}private static object GetSceneHierarchy(){EditorWindow window = GetHierarchyWindow();object sceneHierarchy = typeof(EditorWindow).Assembly.GetType("UnityEditor.SceneHierarchyWindow").GetProperty("sceneHierarchy").GetValue(window);return sceneHierarchy;}private static EditorWindow GetHierarchyWindow(){// For it to open, so that it the current focused window.EditorApplication.ExecuteMenuItem("Window/General/Hierarchy");return EditorWindow.focusedWindow;}
}

完成