展开一个可选值(LLDB)我有一个LoginViewController与viewDidLayoutSubviews()
的功能和作用我有这样的代码来创建文本框底部只有边框内,致命错误:意外发现零,而在的UITextField
let txt_border = CALayer()
let txt_pass_border = CALayer()
let border_width = CGFloat(2.0)
txt_border.borderColor = UIColor.grayColor().CGColor
txt_pass_border.borderColor = UIColor.grayColor().CGColor
txt_border.frame = CGRect(x: 0, y: txt_login_Email.frame.size.height - border_width, width: txt_login_Email.frame.size.width, height: txt_login_Email.frame.size.height)
txt_pass_border.frame = CGRect(x: 0, y: txt_login_Password.frame.size.height - border_width, width: txt_login_Password.frame.size.width, height: txt_login_Password.frame.size.height)
txt_border.borderWidth = border_width
txt_pass_border.borderWidth = border_width
txt_login_Email.layer.addSublayer(txt_border)
txt_login_Email.layer.masksToBounds = true
txt_login_Password.layer.addSublayer(txt_pass_border)
txt_login_Password.layer.masksToBounds = true
什么需要做的改变这个错误?
很有可能txt_login_Emai是无 –
对不起,我不明白你 –
你知道什么是零吗? –