ios – 使用IBDesignable和prepareForInterfaceBuilder与UILabel

在其中有一个UILabel(由于原因,这是在代码中添加而不是在InterfaceBuilder中).

然后,我在MyView上有一个名为color的属性.

我想要的是让Interface Builder能够选择颜色,然后显示标签,并将字体设置为该颜色.

在我的代码中我有……

@IBDesignable class MyView: UIView {

    private let textLabel = UILabel()

    @IBInspectable var color: UIColor = .blackColor() {
        didSet {
            textLabel.textColor = color
        }
    }

    required init(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)

        initialSetup()
    }

    override init(frame: CGRect) {
        super.init(frame: frame)

       initialSetup()
    }

    private func initialSetup() -> Void {
        self.backgroundColor = .clearColor()

        textLabel.textAlignment = .Center
        textLabel.numberOfLines = 0

        addSubview(textLabel)
    }

    override func layoutSubviews() {
        super.layoutSubviews()

        textLabel.frame = bounds
    }

    // I have no idea what I'm doing here?!
    override func prepareForInterfaceBuilder() {
        // should I create a label specifically for here?
        // or should I use the property textLabel?

        textLabel.text = "Hello,world!" // setting place holder IB text?
        textLabel.textColor = color
        textLabel.font = .systemFontOfSize(21)
        textLabel.textAlignment = .Center
        textLabel.numberOfLines = 0

        // do I need to add sub view?
    }

}

IBInspectable

在IB中我可以看到那里的颜色属性,我可以设置它.令人讨厌的是,它采用默认值.clearColor(),但不是我在代码中设置的颜色.有办法解决这个问题吗？

IBDesignable

当我将视图放入InterfaceBuilder时,它显示了所有可检查的属性,但实际视图中没有显示任何内容.

当我运行它一切正常.我希望能够在IB中获得一些工作(除了drawRect).我发现明显缺乏文档.

编辑 – 警告

我刚注意到我发现构建错误/警告说…

warning: IB Designables: Ignoring user defined runtime attribute for key path “color” on instance of “UIView”. Hit an exception when attempting to set its value: [ setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key color.

这可能会改变解决方案:)