Swift: How to resize the font size within a UITextView while using AutoLayout? - ios

Question

I am one week into Swift programing and I want to build my first Application with Autolayout.
The current state of my app is that I generate a bunch of PictureCell in my ViewController. Their size is based on a slider value (and also calculated in the ViewController). This works just fine.
My struggle is customizing the inside of my PictureCell. My goal is to have a Label in the cell which font size is automatically resized when I resize the cell.
At the current state I can resize the Cell and the UITextView like I want, but I cannot resize the font within the Textview because it's constant is just called when it is initialized (I guess).
How can I address this problem in a good way?
Due to a not understanding of Swifts logic I have to post the whole code of the PictureCell:
class PictureCell: UICollectionViewCell {
override init(frame: CGRect) {
super.init(frame: frame)
self.translatesAutoresizingMaskIntoConstraints = false
self.layer.cornerRadius = self.bounds.width / 20
self.clipsToBounds = true
setupViews()
}
let descriptionTextView: UITextView = {
let textView = UITextView()
textView.text = "Header"
textView.textColor = .black
textView.backgroundColor = .white
textView.translatesAutoresizingMaskIntoConstraints = false
textView.textAlignment = .center
textView.isEditable = false
textView.isScrollEnabled = false
textView.sizeToFit()
textView.font = UIFont.boldSystemFont(ofSize: textView.contentSize.height / 2) // Resize that
textView.layer.borderWidth = 2
textView.layer.borderColor = UIColor.red.cgColor
return textView
}()
var mainPicture: UIImageView = {
let imageView = UIImageView()
imageView.contentMode = .scaleAspectFill
imageView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
imageView.clipsToBounds = true
return imageView
}()
func setPictureForIndex(index: Int) {
self.mainPicture.image = UIImage(named: "color\(index)")
}
func setupViews() {
addSubview(mainPicture)
confMainPicture()
addSubview(descriptionTextView)
confDescriptionTextView()
}
func confMainPicture() {
mainPicture.translatesAutoresizingMaskIntoConstraints = false
mainPicture.widthAnchor.constraint(equalTo: self.widthAnchor).isActive = true
mainPicture.heightAnchor.constraint(equalTo: self.heightAnchor).isActive = true
mainPicture.topAnchor.constraint(equalTo: self.topAnchor).isActive = true
mainPicture.bottomAnchor.constraint(equalTo: self.bottomAnchor).isActive = true
}
func confDescriptionTextView(){
descriptionTextView.translatesAutoresizingMaskIntoConstraints = false
descriptionTextView.widthAnchor.constraint(equalTo: self.widthAnchor).isActive = true
descriptionTextView.heightAnchor.constraint(equalTo: mainPicture.heightAnchor, multiplier: 0.25).isActive = true
descriptionTextView.topAnchor.constraint(equalTo: self.topAnchor).isActive = true
}
Too small for the text
Just fine
Too big to look good

Answer 1

This Code solved my problem more or less:
It doesn't work properly if the Cell is really small but it's better than the starting point and maybe someone can use it.
class PictureCell: UICollectionViewCell {
override init(frame: CGRect) {
super.init(frame: frame)
self.translatesAutoresizingMaskIntoConstraints = false
self.layer.cornerRadius = self.bounds.width / 20
self.clipsToBounds = true
setupViews()
}
//MARK: -
var cellIdetifier = Int()
var mainPicture: UIImageView = {
let imageView = UIImageView()
imageView.contentMode = .scaleAspectFill
imageView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
imageView.clipsToBounds = true
imageView.layer.cornerRadius = imageView.bounds.width / 20
return imageView
}()
var descriptionBox: UIView = {
let descVie = UIView()
descVie.backgroundColor = UIColor(red: 0.1 , green: 0.1, blue: 0.1, alpha: 0.5)
descVie.layer.borderWidth = 0.5
descVie.layer.borderColor = UIColor.black.cgColor
descVie.clipsToBounds = true
descVie.layer.cornerRadius = descVie.bounds.height / 5
return descVie
}()
lazy var descLabel: UITextField = {
let label = UITextField()
label.textColor = .white
label.textAlignment = .center
label.clipsToBounds = true
label.font = UIFont.systemFont(ofSize: 15)
label.adjustsFontSizeToFitWidth = true
label.autoresizingMask = [.flexibleWidth,.flexibleHeight]
label.sizeToFit()
label.layoutIfNeeded()
label.isUserInteractionEnabled = false
return label
}()
func setPictureForIndex(index: Int, name: String) {
self.descLabel.text = name
self.mainPicture.image = UIImage(named: "color\(index)")
}
// MARK: -
// MARK: Layout
func setupViews() {
addSubview(mainPicture)
addSubview(descriptionBox)
descriptionBox.addSubview(descLabel)
confBounds()
}
func confBounds() {
mainPicture.translatesAutoresizingMaskIntoConstraints = false
mainPicture.widthAnchor.constraint(equalTo: self.widthAnchor).isActive = true
mainPicture.heightAnchor.constraint(equalTo: self.heightAnchor).isActive = true
mainPicture.topAnchor.constraint(equalTo: self.topAnchor).isActive = true
mainPicture.bottomAnchor.constraint(equalTo: self.bottomAnchor).isActive = true
descriptionBox.translatesAutoresizingMaskIntoConstraints = false
descriptionBox.widthAnchor.constraint(equalTo: self.widthAnchor).isActive = true
descriptionBox.heightAnchor.constraint(equalTo: mainPicture.heightAnchor, multiplier: 0.25).isActive = true
descriptionBox.topAnchor.constraint(equalTo: self.topAnchor).isActive = true
descriptionBox.bottomAnchor.constraint(greaterThanOrEqualTo: mainPicture.topAnchor, constant: 1)
descLabel.translatesAutoresizingMaskIntoConstraints = false
descLabel.widthAnchor.constraint(equalTo: descriptionBox.widthAnchor).isActive = true
descLabel.heightAnchor.constraint(equalTo: descriptionBox.heightAnchor).isActive = true
descLabel.bottomAnchor.constraint(equalTo: descriptionBox.bottomAnchor).isActive = true
descLabel.heightAnchor.constraint(equalTo: descriptionBox.heightAnchor).isActive = true
}
}