修复拖出制作预设时异常的问题

Demo/Runtime/Demo.cs

@@ -96,7 +96,7 @@ namespace XCharts
             var btnPanel = transform.Find("chart_list");
             m_BtnClone = transform.Find("btn_clone").gameObject;
             m_BtnClone.SetActive(false);
-            //ChartHelper.DestroyAllChildren(btnPanel);
+            ChartHelper.DestroyAllChildren(btnPanel);
             foreach (var module in m_ChartModule)
             {
                 var btnName = "btn_" + module.name;

Runtime/Internal/BaseChart.cs

@@ -289,7 +289,7 @@ namespace XCharts
         {
             var labelObject = ChartHelper.AddObject(s_SerieLabelObjectName, transform, chartAnchorMin,
                 chartAnchorMax, chartPivot, new Vector2(chartWidth, chartHeight));
-            // ChartHelper.DestroyAllChildren(labelObject.transform);
+            ChartHelper.DestroyAllChildren(labelObject.transform);
             int count = 0;
             for (int i = 0; i < m_Series.Count; i++)
             {

Runtime/Utility/ChartHelper.cs

@@ -12,6 +12,9 @@ using System.Text.RegularExpressions;
 using UnityEngine;
 using UnityEngine.EventSystems;
 using UnityEngine.UI;
+#if UNITY_EDITOR
+using UnityEditor;
+#endif
 
 namespace XCharts
 {
@@ -74,6 +77,13 @@ namespace XCharts
 
         public static void DestroyAllChildren(Transform parent)
         {
+            if(parent == null) return;
+#if UNITY_EDITOR
+            if (PrefabUtility.IsPartOfAnyPrefab(parent.gameObject))
+            {
+                return;
+            }
+#endif
             while (parent.childCount > 0)
             {
                 var go = parent.GetChild(0);