Adjust the time of spawns of items and enemies in the map to when the player first enters the room.

将地图中物品，敌人生成的时机调整到玩家首次进入房间时。

prefab/roomTemplates/dungeon/chest.tscn

@@ -55,7 +55,6 @@ shape = SubResource("RectangleShape2D_7tsse")
 [node name="Marker2D" type="Marker2D" parent="."]
 position = Vector2(260, 87)
 script = ExtResource("1_y2vgj")
-ResPath = "res://prefab/entitys/DelivererOfDarkMagic.tscn"
 
 [node name="NavigationRegion2D" type="NavigationRegion2D" parent="."]
 navigation_polygon = SubResource("NavigationPolygon_rh1gx")

prefab/roomTemplates/dungeon/horizontalCorridor.tscn

@@ -54,7 +54,6 @@ shape = SubResource("RectangleShape2D_7tsse")
 [node name="Marker2D" type="Marker2D" parent="."]
 position = Vector2(260, 87)
 script = ExtResource("2_wamhd")
-ResPath = "res://prefab/entitys/DelivererOfDarkMagic.tscn"
 
 [node name="NavigationRegion2D" type="NavigationRegion2D" parent="."]
 navigation_polygon = SubResource("NavigationPolygon_rh1gx")

prefab/roomTemplates/tutorials/spellEditor.tscn

@@ -37,7 +37,7 @@ position = Vector2(751.5, 289.438)
 shape = SubResource("RectangleShape2D_jxmys")
 debug_color = Color(0, 0.6, 0.701961, 0.419608)
 
-[node name="Marker2D" type="Marker2D" parent="."]
+[node name="PlayerSpawn" type="Marker2D" parent="."]
 position = Vector2(54, 256)
 script = ExtResource("1_q04qt")
 
@@ -73,16 +73,6 @@ position = Vector2(386, 178)
 scale = Vector2(23.9375, 11.0625)
 texture = ExtResource("3_atgj7")
 
-[node name="Marker2D2" type="Marker2D" parent="."]
-position = Vector2(100, 250)
-script = ExtResource("4_6ihp7")
-ItemId = "staff_necromancy"
-
-[node name="Marker2D3" type="Marker2D" parent="."]
-position = Vector2(134, 248)
-script = ExtResource("4_6ihp7")
-ItemId = "necromancy"
-
 [node name="Label" type="Label" parent="."]
 offset_left = 37.0
 offset_top = 46.0
@@ -115,3 +105,15 @@ position = Vector2(715, 162)
 
 [node name="WoodenBox4" parent="." instance=ExtResource("7_jybe6")]
 position = Vector2(714, 122)
+
+[node name="AutoSpawn" type="Node2D" parent="."]
+
+[node name="necromancy" type="Marker2D" parent="AutoSpawn"]
+position = Vector2(134, 248)
+script = ExtResource("4_6ihp7")
+ItemId = "necromancy"
+
+[node name="staff_necromancy" type="Marker2D" parent="AutoSpawn"]
+position = Vector2(100, 250)
+script = ExtResource("4_6ihp7")
+ItemId = "staff_necromancy"

prefab/roomTemplates/tutorials/tripleShotSpell.tscn

@@ -91,11 +91,6 @@ offset_right = 453.0
 offset_bottom = 151.0
 text = "ui_tutorial_combine_more_powerful_spells"
 
-[node name="Marker2D" type="Marker2D" parent="."]
-position = Vector2(434, 105)
-script = ExtResource("4_fh50l")
-ItemId = "x3"
-
 [node name="WoodenBox" parent="." instance=ExtResource("4_60glh")]
 position = Vector2(711, 179)
 
@@ -129,3 +124,10 @@ position = Vector2(473, 285)
 [node name="TripleShotSpell" type="Sprite2D" parent="."]
 position = Vector2(637, 85)
 texture = ExtResource("6_2qcf3")
+
+[node name="AutoSpawn" type="Node2D" parent="."]
+
+[node name="x3" type="Marker2D" parent="AutoSpawn"]
+position = Vector2(434, 105)
+script = ExtResource("4_fh50l")
+ItemId = "x3"

scripts/EventBus.cs

@@ -9,12 +9,6 @@ namespace ColdMint.scripts;
 /// </summary>
 public static class EventBus
 {
-    /// <summary>
-    /// <para>Event when the AI character is generated</para>
-    /// <para>AI角色生成事件</para>
-    /// </summary>
-    public static Action<AiCharacterGenerateEvent>? AiCharacterGenerateEvent;
-
     /// <summary>
     /// <para>Game Over Event</para>
     /// <para>游戏结束事件</para>

scripts/map/AiCharacterSpawn.cs

@@ -1,5 +1,5 @@
 using ColdMint.scripts.character;
-using ColdMint.scripts.map.events;
+using ColdMint.scripts.map.room;
 using ColdMint.scripts.utils;
 using Godot;
 
@@ -9,52 +9,45 @@ namespace ColdMint.scripts.map;
 /// <para>Ai character generation point</para>
 /// <para>Ai角色生成点</para>
 /// </summary>
-public partial class AiCharacterSpawn : Marker2D
+public partial class AiCharacterSpawn : Marker2D, ISpawnMarker
 {
     private PackedScene? _packedScene;
-    [Export]
+    [Export] private string? _resPath;
-    public string? ResPath;
 
     public override void _Ready()
     {
         base._Ready();
-        if (!string.IsNullOrEmpty(ResPath))
+        if (!string.IsNullOrEmpty(_resPath))
         {
-            _packedScene = GD.Load<PackedScene>(ResPath);
+            _packedScene = GD.Load<PackedScene>(_resPath);
+        }
     }
 
-        EventBus.AiCharacterGenerateEvent += OnAiCharacterGenerateEvent;
+    public Node2D? Spawn()
-    }
-
-    /// <summary>
-    /// <para>When an event is triggered</para>
-    /// <para>当触发事件时</para>
-    /// </summary>
-    /// <param name="aiCharacterGenerateEvent"></param>
-    public void OnAiCharacterGenerateEvent(AiCharacterGenerateEvent aiCharacterGenerateEvent)
     {
-        if (GameSceneDepend.AiCharacterContainer == null)
+        if (GameSceneDepend.AiCharacterContainer == null || _packedScene == null)
         {
-            return;
+            return null;
-        }
-
-        if (_packedScene == null)
-        {
-            return;
         }
 
         var aiCharacter = NodeUtils.InstantiatePackedScene<AiCharacter>(_packedScene);
         if (aiCharacter == null)
         {
-            return;
+            return null;
         }
 
         NodeUtils.CallDeferredAddChild(GameSceneDepend.AiCharacterContainer, aiCharacter);
         aiCharacter.GlobalPosition = GlobalPosition;
+        return aiCharacter;
     }
 
-    public override void _ExitTree()
+    public bool CanQueueFree()
     {
-        EventBus.AiCharacterGenerateEvent -= OnAiCharacterGenerateEvent;
+        return true;
+    }
+
+    public void DoQueueFree()
+    {
+        QueueFree();
     }
 }

scripts/map/ItemSpawn.cs

@@ -1,6 +1,6 @@
 using ColdMint.scripts.debug;
 using ColdMint.scripts.inventory;
-using ColdMint.scripts.map.events;
+using ColdMint.scripts.map.room;
 using Godot;
 
 namespace ColdMint.scripts.map;
@@ -9,36 +9,34 @@ namespace ColdMint.scripts.map;
 /// <para>ItemSpawn</para>
 /// <para>物品出生点</para>
 /// </summary>
-public partial class ItemSpawn : Marker2D
+public partial class ItemSpawn : Marker2D, ISpawnMarker
 {
-    [Export] public string? ItemId { get; private set; }
+    [Export] private string? ItemId { get; set; }
 
-    public override void _Ready()
+    public Node2D? Spawn()
     {
-        base._Ready();
+        if (string.IsNullOrEmpty(ItemId))
-        EventBus.MapGenerationCompleteEvent += MapGenerationCompleteEvent;
-    }
-
-    private void MapGenerationCompleteEvent(MapGenerationCompleteEvent mapGenerationCompleteEvent)
         {
-        //After the map is generated, create the item instance.
+            return null;
-        //当地图生成完成后，创建物品实例。
-        if (ItemId == null)
-        {
-            return;
         }
 
         var item = ItemTypeManager.CreateItem(ItemId, this);
-        LogCat.LogWithFormat("generated_item_is_empty",LogCat.LogLabel.ItemSpawn,true,ItemId,item == null);
+        LogCat.LogWithFormat("generated_item_is_empty", LogCat.LogLabel.ItemSpawn, true, ItemId, item == null);
-        if (item is Node2D node2D)
+        if (item is not Node2D node2D)
         {
-            node2D.GlobalPosition = GlobalPosition;
+            return null;
         }
+        node2D.GlobalPosition = GlobalPosition;
+        return node2D;
     }
 
-    public override void _ExitTree()
+    public bool CanQueueFree()
     {
-        base._ExitTree();
+        return true;
-        EventBus.MapGenerationCompleteEvent -= MapGenerationCompleteEvent;
+    }
+
+    public void DoQueueFree()
+    {
+        QueueFree();
     }
 }

scripts/map/MapGenerator.cs

@@ -311,11 +311,6 @@ public static class MapGenerator
             RoomDictionary = roomDictionary
         };
         EventBus.MapGenerationCompleteEvent?.Invoke(eventObj);
-        var aiCharacterGenerateEvent = new AiCharacterGenerateEvent
-        {
-            Tag = AiCharacterGenerateEvent.TagMapGenerationComplete
-        };
-        EventBus.AiCharacterGenerateEvent?.Invoke(aiCharacterGenerateEvent);
     }
 
 

scripts/map/PlayerSpawn.cs

@@ -2,6 +2,7 @@
 using ColdMint.scripts.character;
 using ColdMint.scripts.debug;
 using ColdMint.scripts.map.events;
+using ColdMint.scripts.map.room;
 using ColdMint.scripts.utils;
 using Godot;
 
@@ -11,7 +12,7 @@ namespace ColdMint.scripts.map;
 /// <para>PlayerSpawn</para>
 /// <para>玩家出生点</para>
 /// </summary>
-public partial class PlayerSpawn : Marker2D
+public partial class PlayerSpawn : Marker2D,ISpawnMarker
 {
     private PackedScene? _playerPackedScene;
 
@@ -31,32 +32,49 @@ public partial class PlayerSpawn : Marker2D
             GameSceneDepend.Player.GlobalPosition = GlobalPosition;
             return;
         }
-
+        Spawn();
-        SpawnPlayer();
     }
     
-    /// <summary>
+
-    /// <para>Generate player instance</para>
+    private void MapGenerationCompleteEvent(MapGenerationCompleteEvent mapGenerationCompleteEvent)
-    /// <para>生成玩家实例</para>
+    {
-    /// </summary>
+        //After the map is generated, create the player instance.
-    private void SpawnPlayer()
+        //当地图生成完成后，创建玩家实例。
+        if (GameSceneDepend.Player != null)
+        {
+            //An existing player instance will not be created.
+            //已经存在玩家实例，不再创建。
+            return;
+        }
+
+        Spawn();
+    }
+
+    public override void _ExitTree()
+    {
+        base._ExitTree();
+        EventBus.MapGenerationCompleteEvent -= MapGenerationCompleteEvent;
+        EventBus.GameReplayEvent -= GameReplayEvent;
+    }
+
+    public Node2D? Spawn()
     {
         if (GameSceneDepend.PlayerContainer == null)
         {
-            return;
+            return null;
         }
 
         if (_playerPackedScene == null)
         {
             LogCat.LogError("player_packed_scene_not_exist");
-            return;
+            return null;
         }
 
         var playerNode =
             NodeUtils.InstantiatePackedScene<Player>(_playerPackedScene);
         if (playerNode == null)
         {
-            return;
+            return null;
         }
 
         //The player's parent node must be GameSceneDepend PlayerContainer.
@@ -73,26 +91,16 @@ public partial class PlayerSpawn : Marker2D
         playerNode.ItemContainer = itemContainer;
         GameSceneDepend.Player = playerNode;
         playerNode.GlobalPosition = GlobalPosition;
+        return playerNode;
     }
 
-    private void MapGenerationCompleteEvent(MapGenerationCompleteEvent mapGenerationCompleteEvent)
+    public bool CanQueueFree()
     {
-        //After the map is generated, create the player instance.
+        return false;
-        //当地图生成完成后，创建玩家实例。
-        if (GameSceneDepend.Player != null)
-        {
-            //An existing player instance will not be created.
-            //已经存在玩家实例，不再创建。
-            return;
     }
 
-        SpawnPlayer();
+    public void DoQueueFree()
-    }
-
-    public override void _ExitTree()
     {
-        base._ExitTree();
+        QueueFree();
-        EventBus.MapGenerationCompleteEvent -= MapGenerationCompleteEvent;
-        EventBus.GameReplayEvent -= GameReplayEvent;
     }
 }

scripts/map/events/AiCharacterGenerateEvent.cs

@@ -1,23 +0,0 @@
-namespace ColdMint.scripts.map.events;
-
-/// <summary>
-/// <para>AiCharacterGenerateEvent</para>
-/// <para>Ai角色生成事件</para>
-/// </summary>
-public class AiCharacterGenerateEvent
-{
-    /// <summary>
-    /// <para>Map generation completed Tag</para>
-    /// <para>地图生成完成的Tag</para>
-    /// </summary>
-    public const string TagMapGenerationComplete = "MapGenerationComplete";
-    
-
-    /// <summary>
-    /// <para>The Tag used to generate the role</para>
-    /// <para>生成角色时使用的Tag</para>
-    /// </summary>
-    // ReSharper disable UnusedAutoPropertyAccessor.Global
-    public string? Tag { get; set; }
-    // ReSharper restore UnusedAutoPropertyAccessor.Global
-}

scripts/map/room/IEnterRoomEventHandler.cs

@@ -19,7 +19,11 @@ public interface IEnterRoomEventHandler
     /// <para>When entering the room</para>
     /// <para>当进入房间时</para>
     /// </summary>
+    /// <param name="playerRoomVisitCount">
+    ///<para>The number of times the player visits the room, 1 is the first visit.</para>
+    ///<para>玩家访问房间的次数，为1则代表首次访问。</para>
+    /// </param>
     /// <param name="node"></param>
     /// <param name="room"></param>
-    void OnEnterRoom(Node node,Room room);
+    void OnEnterRoom(int playerRoomVisitCount,Node node,Room room);
 }

scripts/map/room/ISpawnMarker.cs

@@ -0,0 +1,33 @@
+using Godot;
+
+namespace ColdMint.scripts.map.room;
+
+/// <summary>
+/// <para>The tag of the generated entity</para>
+/// <para>生成实体的标记</para>
+/// </summary>
+public interface ISpawnMarker
+{
+    /// <summary>
+    /// <para>Generating entity</para>
+    /// <para>生成实体</para>
+    /// </summary>
+    /// <remarks>
+    ///<para>Return the result of the generation. If null is returned, the generation fails.</para>
+    ///<para>返回生成结果，为null则生成失败。</para>
+    /// </remarks>
+    Node2D? Spawn();
+
+    /// <summary>
+    /// <para>Can Queue Free</para>
+    /// <para>可释放节点吗</para>
+    /// </summary>
+    /// <returns></returns>
+    bool CanQueueFree();
+
+    /// <summary>
+    /// <para>Execute Queue Free</para>
+    /// <para>执行释放节点</para>
+    /// </summary>
+    void DoQueueFree();
+}

scripts/map/room/Room.cs

@@ -29,6 +29,18 @@ public class Room
     private bool _hasPlayer;
     private readonly List<CharacterTemplate> _characterTemplateList = [];
     
+    /// <summary>
+    /// <para>When the player first enters the room, all <see cref="ISpawnMarker"/> nodes under this node are executed</para>
+    /// <para>当玩家首次进入房间时，会执行此节点下所有<see cref="ISpawnMarker"/>节点</para>
+    /// </summary>
+    private Node2D? _autoSpawn;
+
+    /// <summary>
+    /// <para>The number of times the player visits the room</para>
+    /// <para>玩家访问房间的次数</para>
+    /// </summary>
+    private int PlayerRoomVisitCount { get; set; }
+
     public string? EnterRoomEventHandlerId { get; set; }
 
     public string? ExitRoomEventHandlerId { get; set; }
@@ -51,47 +63,31 @@ public class Room
     }
 
     /// <summary>
-    ///  <para>Places a barrier in a slot where a match has been found.</para>
+    /// <para>Place barriers in all slots</para>
-    /// <para>在找到匹配的槽位放置屏障。</para>
+    /// <para>在所有的槽位放置屏障</para>
     /// </summary>
-    private void PlaceBarrierInMatchedSlot()
+    public void PlaceBarriersInAllSlots()
     {
-        ProcessRoomSlots(action: (roomSlot, ground, barrier, i) =>
+        var barrier = GetTileMapLayer(Config.TileMapLayerName.Barrier);
-        {
+        if (barrier == null)
-            if (!roomSlot.Matched)
         {
             return;
         }
-            var cellSourceId = barrier.GetCellSourceId(i);
+        barrier.Enabled = true;
-            if (cellSourceId == -1)
-            {
-                return;
-            }
-
-            ground.SetCell(i, cellSourceId, barrier.GetCellAtlasCoords(i), barrier.GetCellAlternativeTile(i));
-        });
     }
 
     /// <summary>
-    /// <para>Clear the barrier that finds a matching slot</para>
+    /// <para>Clear all matched barriers</para>
-    /// <para>清空找到匹配的槽位的屏障。</para>
+    /// <para>清空所有已匹配位置的屏障</para>
     /// </summary>
-    private void ClearBarriersInMatchedSlots()
+    public void ClearAllMatchedBarriers()
     {
-        ProcessRoomSlots(action: (roomSlot, ground, barrier, i) =>
+        var barrier = GetTileMapLayer(Config.TileMapLayerName.Barrier);
-        {
+        if (barrier == null)
-            if (!roomSlot.Matched)
         {
             return;
         }
-            var cellSourceId = barrier.GetCellSourceId(i);
+        barrier.Enabled = false;
-            if (cellSourceId == -1)
-            {
-                return;
-            }
-
-            ground.SetCell(i, cellSourceId, barrier.GetCellAtlasCoords(i), barrier.GetCellAlternativeTile(i));
-        });
     }
 
     /// <summary>
@@ -99,32 +95,6 @@ public class Room
     /// <para>在未匹配的槽位放置屏障。</para>
     /// </summary>
     public void PlaceBarrierInUnmatchedSlots()
-    {
-        ProcessRoomSlots(action: (roomSlot, ground, barrier, i) =>
-        {
-            if (roomSlot.Matched)
-            {
-                return;
-            }
-            var cellSourceId = barrier.GetCellSourceId(i);
-            if (cellSourceId == -1)
-            {
-                return;
-            }
-
-            ground.SetCell(i, cellSourceId, barrier.GetCellAtlasCoords(i), barrier.GetCellAlternativeTile(i));
-        });
-    }
-
-    /// <summary>
-    /// <para>Executes a callback for each room slot, providing the corresponding coordinates in the barrier and ground layers.</para>
-    /// <para>对每个房间槽位执行回调，提供barrier层和ground层对应的坐标。</para>
-    /// </summary>
-    /// <param name="action">
-    ///<para>The callback action to be executed, which takes the barrier layer, ground layer, and coordinates as parameters.</para>
-    ///<para>要执行的回调操作，它以屏障层、底层和坐标作为参数。</para>
-    /// </param>
-    private void ProcessRoomSlots(Action<RoomSlot, TileMapLayer, TileMapLayer, Vector2I> action)
     {
         var ground = GetTileMapLayer(Config.TileMapLayerName.Ground);
         var barrier = GetTileMapLayer(Config.TileMapLayerName.Barrier);
@@ -149,12 +119,22 @@ public class Room
             //将屏障层的对应坐标瓦片放到地面层。
             CoordinateUtils.ForEachCell(roomSlot.StartPosition, roomSlot.EndPosition, i =>
             {
-                action.Invoke(roomSlot, ground, barrier, i);
+                if (roomSlot.Matched)
+                {
+                    return;
+                }
+                var cellSourceId = barrier.GetCellSourceId(i);
+                if (cellSourceId == -1)
+                {
+                    return;
+                }
+                ground.SetCell(i, cellSourceId, barrier.GetCellAtlasCoords(i), barrier.GetCellAlternativeTile(i));
             });
         }
-        barrier.QueueFree();
+        barrier.Enabled = false;
     }
 
+
     /// <summary>
     /// <para>ShowAllCharacterTemplate</para>
     /// <para>显示所有角色模板</para>
@@ -200,6 +180,15 @@ public class Room
         {
             _characterTemplateList.Add(player);
             _hasPlayer = true;
+            PlayerRoomVisitCount++;
+            if (PlayerRoomVisitCount == 1 && _autoSpawn != null)
+            {
+                NodeUtils.ForEachNode<ISpawnMarker>(_autoSpawn, marker =>
+                {
+                    marker.Spawn();
+                    return false;
+                });
+            }
             //The player enters the room, opening up their view.
             //玩家进入了房间，开放视野。
             if (_pointLight2D != null)
@@ -231,7 +220,7 @@ public class Room
         }
 
         var enterRoomEventHandler = RoomEventManager.GetEnterRoomEventHandler(EnterRoomEventHandlerId);
-        enterRoomEventHandler?.OnEnterRoom(node, this);
+        enterRoomEventHandler?.OnEnterRoom(PlayerRoomVisitCount, node, this);
     }
 
 
@@ -260,8 +249,18 @@ public class Room
                 _pointLight2D.Show();
                 _pointLight2D.Texture = AssetHolder.White25;
             }
-
             HideAllCharacterTemplate();
+            if (PlayerRoomVisitCount == 1 && _autoSpawn != null)
+            {
+                NodeUtils.ForEachNode<ISpawnMarker>(_autoSpawn, marker =>
+                {
+                    if (marker.CanQueueFree())
+                    {
+                        marker.DoQueueFree();
+                    }
+                    return false;
+                });
+            }
         }
         else if (node is CharacterTemplate characterTemplate && characterTemplate.Visible)
         {
@@ -312,8 +311,8 @@ public class Room
             return;
         }
 
-        var node2D = NodeUtils.InstantiatePackedScene<Node2D>(packedScene);
+        var rootNode = NodeUtils.InstantiatePackedScene<Node2D>(packedScene);
-        if (node2D == null)
+        if (rootNode == null)
         {
             //The room node is not of Node2D type. An exception is thrown
             //房间节点不是Node2D类型，抛出异常
@@ -321,15 +320,15 @@ public class Room
             return;
         }
 
-        _rootNode = node2D;
+        _rootNode = rootNode;
-        var tileMapNode = node2D.GetNode<Node2D>("TileMap");
+        var tileMapNode = rootNode.GetNode<Node2D>("TileMap");
         NodeUtils.ForEachNode<TileMapLayer>(tileMapNode, node =>
         {
             _tileMapLayers ??= [];
             _tileMapLayers.Add(node);
             return false;
         });
-        _area2D = node2D.GetNode<Area2D>("RoomArea");
+        _area2D = rootNode.GetNode<Area2D>("RoomArea");
         _area2D.Monitoring = true;
         _area2D.SetCollisionLayerValue(Config.LayerNumber.RoomArea, true);
         //Sets the collision layer that can be detected in the current room area.
@@ -340,12 +339,13 @@ public class Room
         _area2D.BodyEntered += OnEnterRoom;
         _collisionShape2D = _area2D.GetChild<CollisionShape2D>(0);
         _roomSlots = GetRoomSlots(GetTileMapLayer(Config.TileMapLayerName.Ground), _area2D,
-            node2D.GetNode<Node2D>("RoomSlotList"));
+            rootNode.GetNode<Node2D>("RoomSlotList"));
-        _pointLight2D = node2D.GetNodeOrNull<PointLight2D>("PointLight2D");
+        _pointLight2D = rootNode.GetNodeOrNull<PointLight2D>("PointLight2D");
         if (_pointLight2D != null)
         {
             _pointLight2D.BlendMode = Light2D.BlendModeEnum.Mix;
         }
+        _autoSpawn = rootNode.GetNodeOrNull<Node2D>("AutoSpawn");
     }
 
     public Node2D? RootNode => _rootNode;

scripts/utils/NodeUtils.cs

@@ -131,10 +131,10 @@ public static class NodeUtils
     ///<para>用于处理回调的函数，返回true终止遍历节点</para>
     /// </param>
     /// <typeparam name="T">
-    ///<para>When the type is specified as Node, all child nodes are returned.</para>
+    ///<para>Specifies the generic type</para>
-    ///<para>当指定类型为Node时，将返回所有子节点。</para>
+    ///<para>指定的泛型</para>
     /// </typeparam>
-    public static void ForEachNode<T>(Node parent, Func<T, bool> func) where T : Node
+    public static void ForEachNode<T>(Node parent, Func<T, bool> func) where T : class
     {
         var count = parent.GetChildCount();
         if (count <= 0)