展开Optional时意外发现nil

本文介绍了展开Optional时意外发现nil的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述 @IBOutlet weak var groupNameTF: UITextField! var group: Group? { didSet { groupNameTF.text = group?.name } }

无法理解此处的可选问题.从日志中可以看到，group不是nil.正如我认为的那样，我确实可以安全地进行价值包装.我还检查了if let的构造，结果相同.

Can't understand what the problem with optional here. As I see from logs, group isn't nil. As I thought I do safe value unwrapping. I also checked with if let construction, same result.

推荐答案

由于groupNameTF为nil，最有可能发生这种情况.一种快速的解决方法是使用if来保护它:

Most likely that happens because groupNameTF is nil. A quick workaround is to protect that with an if:

var group: Group? { didSet { if groupNameTF != nil { groupNameTF.text = group?.name } } }