Hi, I had the same problem。 Then I repeated the question。 for the following reasons：
look this code：
0 [self.view bringSubviewToFront:self.educationView];
1 [_educationView buildCustomView];
Line 0： self.educationView Is a lazy load， therein create the UI, and also call buildCustomView method, （There is customization UITextFiled involved in this method）
Line 1： It's called again the buildCustomView method
A crash occurs when the UITextField is released through the stack discovery， So I commented Line 1 code out， Then the problem was solved。
You can check to see if such code exists
PixelCoder
Users receive reputation points by contributing quality content to the forums.
Posts include post and replies published on the forums.
Post authors can mark replies as Accepted to indicate successful solutions.
Apple Developer Forums admins can mark replies as Apple Recommended to indicate an approved solution