I get null reference exception when switching external behaviour tree

[Roofen]

测试后启动行为树不执行，加载外部行为树没有问题，当我按如下方式切换行为树时出现异常，偶尔会影响行为树的执行。我在行为树中切换外部行为树。

 

[Justin]

Please use English so it's easier for others to find similar topics.

With that said, I just tried to reproduce that error but wasn't able to. Can you tell me how to reproduce it from a fresh project?