iOS 9 UIButton初始化

Question

我试图以UIButton编程方式初始化,但看到以下错误之一:

buttonWithType不可用:使用对象构造UIButton(类型:)

要么

错误:调用中的参数标签不正确(有'buttonWithType:',期望'类型:')

  for char in keys {
        let btn: UIButton = UIButton.buttonWithType(UIButtonType.System) as UIButton

        btn.frame = CGRectMake(0, 0, 20, 20)
        btn.setTitle(char, forState: .Normal)
        btn.sizeToFit()
        btn.titleLabel?.font = UIFont.systemFontOfSize(20)

        btn.backgroundColor = UIColor(hue: (216/360.0), saturation: 0.1, brightness: 0.81, alpha: 1)//
        btn.setTitleColor(UIColor(white: 1.0, alpha: 1.0), forState: .Normal)

        btn.setContentHuggingPriority(1000, forAxis: .Horizontal)
        btn.setContentCompressionResistancePriority(1000, forAxis: .Horizontal)

        btn.addTarget(self, action: Selector("handleBtnPress:"), forControlEvents: .TouchUpInside)

        self.addSubview(btn)
    }

Answer 1

便利初始化程序UIButton已更改.

convenience init(type buttonType: UIButtonType)

斯威夫特3:

let btn = UIButton(type: .system) // note the lower case s

Swift 2.x:

let btn = UIButton(type: .System)