Text padding on UILabel - ios

Question

Here, I am trying to have a label with some padding (left, right, top and bottom) around the text.
This issue has related post on SOF and after reading a few of them, I tried using a solution proposed here:
This is the code for my subclassing UILabel:
import UIKit
class LuxLabel: UILabel {
//let padding: UIEdgeInsets
var padding: UIEdgeInsets = UIEdgeInsets.zero {
didSet {
self.invalidateIntrinsicContentSize()
}
}
// Create a new PaddingLabel instance programamtically with the desired insets
required init(padding: UIEdgeInsets = UIEdgeInsets(top: 0, left: 10, bottom: 0, right: 10)) {
self.padding = padding
super.init(frame: CGRect.zero)
}
// Create a new PaddingLabel instance programamtically with default insets
override init(frame: CGRect) {
padding = UIEdgeInsets.zero // set desired insets value according to your needs
super.init(frame: frame)
}
// Create a new PaddingLabel instance from Storyboard with default insets
required init?(coder aDecoder: NSCoder) {
padding = UIEdgeInsets.zero // set desired insets value according to your needs
super.init(coder: aDecoder)
}
override func drawText(in rect: CGRect) {
super.drawText(in: UIEdgeInsetsInsetRect(rect, padding))
}
// Override `intrinsicContentSize` property for Auto layout code
override var intrinsicContentSize: CGSize {
let superContentSize = super.intrinsicContentSize
let width = superContentSize.width + padding.left + padding.right
let heigth = superContentSize.height + padding.top + padding.bottom
return CGSize(width: width, height: heigth)
}
}
It is based on PaddingLabel (cf. the above link).
It is mostly working well, but for some reasons that I do not understand, there are cases where things go wrong and the display gets truncated.
This is an example:
The string to put on the label is:
"It has a square shape and a blue color."
The code to create the label is:
let label = LuxLabel(padding: UIEdgeInsets(top: 5, left: 10, bottom: 5, right: 10))
label.numberOfLines = 0
and this is the result:
If I add this line to the two above:
label.lineBreakMode = .byWordWrapping
the result is:
I have also set some constraints. All this works 95% of the time. Can anyone see what is the problem?

Answer 1

Try calling invalidateIntrinsicContentSize:
var padding: UIEdgeInsets = UIEdgeInsets.zero {
didSet {
self.invalidateIntrinsicContentSize()
}
}
EDIT:
I have tried different options. If you update the frame size with the intrinsicContentSize in layoutSubviews that make the trick but I don't know if there is a better way to do it:
override func layoutSubviews() {
super.layoutSubviews()
self.frame.size = self.intrinsicContentSize
}