Unity 修改Prefab实例将Transform变为RectTransform
引用：Is there a way to destroy/replace a GameObject that is inside or part of a Prefab instance?
Changing Transform on a Prefab instance (jiantou) is not allowed.
这里用到的需求是做ui特效时将3Dmesh 渲染到ui层，用的ugui，ugui依赖于RectTransform，所以就有这个问题
将Prefab应用的Model对象的Transform修改为RectTransform
默认Model对象导入Transform组件，但是在ui中有些组件需要RectTransform组件，所以就需要强制将Transform变为RectTransform，这里通过调整Hierarchy面板内的prefab实例并且应用到prefab中，来完成修改，当然还有一个简单方法就是直接修改prefab
/// RectTransform
///
private void AddComponentFromPrefab<T>(GameObject obj) where T :UnityEngine.Component
{
PrefabAssetType prefabType = PrefabUtility.GetPrefabAssetType(obj);
//Debug.Log($"AddComponentFromPrefab,name:{obj.name},PrefabAssetType:{prefabType}");
switch (prefabType)
{
case PrefabAssetType.Regular:
case PrefabAssetType.Variant:
//获取prefab实例的根节点
GameObject prefabRoot = PrefabUtility.GetOutermostPrefabInstanceRoot(obj);
//获取prefab资源，在project中的
GameObject prefabAsset = PrefabUtility.GetCorrespondingObjectFromSource(obj);
//Object prefabAsset = PrefabUtility.GetCorrespondingObjectFromOriginalSource(obj);
//获取资源的路径名字
string assetPath = AssetDatabase.GetAssetPath(prefabAsset);
//Debug.Log(assetPath);
//断开Model的联系，如果是Model是禁止修改RectTransform的
PrefabUtility.UnpackPrefabInstance(prefabRoot, PrefabUnpackMode.Completely, InteractionMode.AutomatedAction); //有个不足的地方是prefab的继承关系会丢失,这里是完全断开连接，非完全的方式没有测试
PrefabUtility.SaveAsPrefabAssetAndConnect(prefabRoot, assetPath, InteractionMode.AutomatedAction);
//修改prefab的RectTransform，如果修改实例的RectTransfom是失败的（Model虽然断开连接，但是还是禁止直接修改prefab实例的RectTransfom）
GameObject pobj = PrefabUtility.LoadPrefabContents(assetPath);
var ts=pobj.GetComponentsInChildren<Transform>();
foreach (var t in ts)
if (!(t is RectTransform))
t.gameObject.AddComponent<T>();
PrefabUtility.SaveAsPrefabAsset(pobj, assetPath);
PrefabUtility.UnloadPrefabContents(pobj);
break;
case PrefabAssetType.Model:
PrefabUtility.UnpackPrefabInstanceAndReturnNewOutermostRoots(obj, PrefabUnpackMode.Completely);
if (!(obj.transform is T))
obj.AddComponent<T>();
break;
default:
break;
}
}
测试
AddComponentFromPrefab<RectTransform>(gameObject);
将测试代码写到Start方法中，且脚本设置[ExecuteInEditMode]标签，挂载prefab跟节点，
测试结果：
结果：
执行代码后Model引用变为prefab内的普通物体，切换修改成功RectTransform，并且prefab也已经修改成功
Prefab和GameObject的正向和逆向查找引用
转自 Unity研究院之Prefab和GameObject的正向和逆向查找引用
[MenuItem("Assets/Check Prefab Use ?")]
private static void OnSearchForReferences()
{
//确保鼠标右键选择的是一个Prefab
if(Selection.gameObjects.Length != 1)
{
return;
}
//遍历所有游戏场景
foreach(EditorBuildSettingsScene scene in EditorBuildSettings.scenes)
{
if(scene.enabled)
{
//打开场景
EditorApplication.OpenScene(scene.path);
//获取场景中的所有游戏对象
GameObject []gos = (GameObject[])FindObjectsOfType(typeof(GameObject));
foreach(GameObject go in gos)
{
//判断GameObject是否为一个Prefab的引用
if(PrefabUtility.GetPrefabType(go) == PrefabType.PrefabInstance)
{
UnityEngine.Object parentObject = EditorUtility.GetPrefabParent(go);
string path = AssetDatabase.GetAssetPath(parentObject);
//判断GameObject的Prefab是否和右键选择的Prefab是同一路径。
if(path == AssetDatabase.GetAssetPath(Selection.activeGameObject))
{
//输出场景名，以及Prefab引用的路径
Debug.Log(scene.path + " " + GetGameObjectPath(go));
}
}
}
}
}
}
public static string GetGameObjectPath(GameObject obj)
{
string path = "/" + obj.name;
while (obj.transform.parent != null)
{
obj = obj.transform.parent.gameObject;
path = "/" + obj.name + path;
}
return path;
}
Unity2018.4的Prefab Variant(Prefab变种)功能
转自[Unity]Unity2018.4的Prefab Variant(Prefab变种)功能
Unity 2018.4中送了一个新的功能: Prefab Variant
思路是, Prefab Variant 继承于一个父Prefab, 父Prefab属性修改后:
-
(1)如果子Prefab的某些属性不动, 则父Prefab的属性影响子Prefab的属性, 此为 [属性继承]
-
(2)如果对子Prefab的某些属性进行修改/覆盖, 则父Prefab的属性无法影响, 此为 [属性定制]
创建Prefab Variant的方法为: 把Prefab从Hierarchy再次拉到Project中,选择 Prefab Variant
用处举例:
比如做一个UGUI窗体模板, 上面有标题文字和关闭按钮
邮件窗体继承于此窗体模板,制作成为一个PrefabVariant, 但是标题文字定制修改为”邮件”
这时,可以通过修改窗体模板中的关闭按钮,对所有派生的窗体按钮进行修改
附:以下为官方对PrefabAssetType的解释:
public enum PrefabAssetType
{
//
// 摘要:
// The object being queried is not part of a Prefab at all.
NotAPrefab = 0, // 不是Prefab
//
// 摘要:
// The object being queried is part of a regular Prefab.
Regular = 1, // 常规的Prefab
//
// 摘要:
// The object being queried is part of a Model Prefab.
Model = 2, // 模型(例如:FBX)
//
// 摘要:
// The object being queried is part of a Prefab Variant.
// A Variant Prefab is a Prefab that is derived from another Prefab,
// that be could be a Regular, Model or even Variant Prefab.
Variant = 3, // Prefab变种
//
// 摘要:
// The object being queried is part of a Prefab instance, but because the asset
// it missing the actual type of Prefab can’t be determined.
MissingAsset = 4 // Prefab实例化出来的对象,但是Prefab被删了(红色)
}