Swift - Labels width is not accurate

Question

I am using the code to create borders for my labels here:

extension CALayer {

func addBorder(edge: UIRectEdge, color: UIColor, thickness: CGFloat) {

    let border = CALayer()

    switch edge {
    case UIRectEdge.top:
        border.frame = CGRect(x: 0, y: 0, width: self.frame.width, height: thickness)
        break
    case UIRectEdge.bottom:
        border.frame = CGRect(x: 0, y: self.frame.height - thickness, width: self.frame.width, height: thickness)
        break
    case UIRectEdge.left:
        border.frame = CGRect(x: 0, y: 0, width: thickness, height: self.frame.height)
        break
    case UIRectEdge.right:
        border.frame = CGRect(x: self.frame.width - thickness, y: 0, width: thickness, height: self.frame.height)
        break
    default:
        break
    }

    border.backgroundColor = color.cgColor;

    self.addSublayer(border)
}

}

However, when I add this to my layers this is what I get: as you can see, the width is totally messed up and the frame.width is inaccurate.

Im not sure why this could be. I don't set the width in my storyboard because I want the label to work for all phone widths.

Thanks for the help in advance!

Answer 1

A CALayer doesn't automatically resize when its corresponding UIView does. You need to override layoutSubviews in the UIView and update your borders widths/heights

override func layoutSubviews() {
    super.layoutSubviews()
    ...resize layer or redraw borders here...
}

You could make a BorderedLabel subclass of UILabel that handled all this logic for you.

EDIT

If you don't want to deal with creating a subclass of UITableViewCell and adding your own BorderedLabel views, you may just need to force the layout before setting the border.

I'm just guessing, since you haven't shared any code, but if you are calling label.text="4517 Bedford..." and then label.layer.addBorder() all you need to do is call layoutIfNeeded() to trigger a layout pass before you addBorder method measures the frame size.

cell.label.text = "4517 Bedford..."
cell.layoutIfNeeded()
cell.label.layer.addBorder(...)