Wrap label around UIbutton - ios

I'm trying to create a view like below using storyboard in Xcode.
For this, I've added a button and a label with constraints but this is the result I get. The text doesn't start below the checkbox. One way to achieve this would be to create 2 labels and add the strings that start after this string to 2 label and place it under the first label.
Is there any better way to do this? Also, when you click on Read more the text can expand as well.

You can make the leading of the button and the label the same ( button above label ) and insert some empty characters at the beginning of the label text

You can do a way. Take the button and the label in a view
then sub divide the view into two views, left one holds the button and right one holds the label. make a gap between left and right
button's constraint will be leading , top and trailing to zero and height as your wish
label's constraint will be leading , top, trailing and bottom.

You can accomplish this by using a UITextView and setting an ExclusionPath.
The ExclusionPath (or paths) defines an area within the text view's textContainer around which the text should wrap.
If you disable scrolling, selection and editing of the UITextView it will behave just like a UILabel but will also give you the benefit of ExclusionPath
Here is a simple example - lots of hard-coded values, so you'd probably want to make it a custom class - but this should get you on your way:
class TextViewLabel: UITextView {
override init(frame: CGRect, textContainer: NSTextContainer?) {
super.init(frame: frame, textContainer: textContainer)
commonInit()
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
commonInit()
}
func commonInit() -> Void {
isScrollEnabled = false
isEditable = false
isSelectable = false
textContainerInset = UIEdgeInsets.zero
textContainer.lineFragmentPadding = 0
}
}
class ExclusionViewController: UIViewController {
let checkBox: UIButton = {
let v = UIButton()
v.translatesAutoresizingMaskIntoConstraints = false
return v
}()
let theTextViewLabel: TextViewLabel = {
let v = TextViewLabel()
v.translatesAutoresizingMaskIntoConstraints = false
v.backgroundColor = .yellow
v.text = "I agree to receive information about this application and all the updates related to this..."
v.font = UIFont.systemFont(ofSize: 20.0)
return v
}()
var isChecked: Bool = false
override func viewDidLoad() {
super.viewDidLoad()
view.addSubview(theTextViewLabel)
theTextViewLabel.addSubview(checkBox)
let cbWidth = CGFloat(20)
NSLayoutConstraint.activate([
theTextViewLabel.topAnchor.constraint(equalTo: view.topAnchor, constant: 100.0),
theTextViewLabel.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 40.0),
theTextViewLabel.widthAnchor.constraint(equalToConstant: 240.0),
checkBox.topAnchor.constraint(equalTo: theTextViewLabel.topAnchor, constant: 2.0),
checkBox.leadingAnchor.constraint(equalTo: theTextViewLabel.leadingAnchor, constant: 0.0),
checkBox.widthAnchor.constraint(equalToConstant: cbWidth),
checkBox.heightAnchor.constraint(equalToConstant: cbWidth),
])
theTextViewLabel.textContainer.exclusionPaths = [
UIBezierPath(rect: CGRect(x: 0, y: 0, width: cbWidth + 8.0, height: cbWidth))
]
updateCheckboxImage()
checkBox.addTarget(self, action: #selector(checkBoxTapped), for: .touchUpInside)
}
func updateCheckboxImage() -> Void {
if isChecked {
checkBox.setImage(UIImage(named: "SmallChecked"), for: .normal)
} else {
checkBox.setImage(UIImage(named: "SmallUnChecked"), for: .normal)
}
}
#objc func checkBoxTapped() -> Void {
isChecked = !isChecked
updateCheckboxImage()
}
}
Result:
(I used these two images for the checkBox):

Related

UILabel not clickable in stack view programmatically created Swift

My question and code is based on this answer to one of my previous questions. I have programmatically created stackview where several labels are stored and I'm trying to make these labels clickable. I tried two different solutions:
Make clickable label. I created function and assigned it to the label in the gesture recognizer:
public func setTapListener(_ label: UILabel){
let tapGesture: UITapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(tapGestureMethod(_:)))
tapGesture.numberOfTapsRequired = 1
tapGesture.numberOfTouchesRequired = 1
label.isUserInteractionEnabled = true
label.addGestureRecognizer(tapGesture)
}
#objc func tapGestureMethod(_ gesture: UITapGestureRecognizer) {
print(gesture.view?.tag)
}
but it does not work. Then below the second way....
I thought that maybe the 1st way does not work because the labels are in UIStackView so I decided to assign click listener to the stack view and then determine on which view we clicked. At first I assigned to each of labels in the stackview tag and listened to clicks:
let tap = UITapGestureRecognizer(target: self, action: #selector(didTapCard(sender:)))
labelsStack.addGestureRecognizer(tap)
....
#objc func didTapCard (sender: UITapGestureRecognizer) {
(sender.view as? UIStackView)?.arrangedSubviews.forEach({ label in
print((label as! UILabel).text)
})
}
but the problem is that the click listener works only on the part of the stack view and when I tried to determine on which view we clicked it was not possible.
I think that possibly the problem is with that I tried to assign one click listener to several views, but not sure that works as I thought. I'm trying to make each label in the stackview clickable, but after click I will only need getting text from the label, so that is why I used one click listener for all views.
Applying a transform to a view (button, label, view, etc) changes the visual appearance, not the structure.
Because you're working with rotated views, you need to implement hit-testing.
Quick example:
override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
// convert the point to the labels stack view coordinate space
let pt = labelsStack.convert(point, from: self)
// loop through arranged subviews
for i in 0..<labelsStack.arrangedSubviews.count {
let v = labelsStack.arrangedSubviews[i]
// if converted point is inside subview
if v.frame.contains(pt) {
return v
}
}
return super.hitTest(point, with: event)
}
Assuming you're still working with the MyCustomView class and layout from your previous questions, we'll build on that with a few changes for layout, and to allow tapping the labels.
Complete example:
class Step5VC: UIViewController {
// create the custom "left-side" view
let myView = MyCustomView()
// create the "main" stack view
let mainStackView = UIStackView()
// create the "bottom labels" stack view
let bottomLabelsStack = UIStackView()
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .systemYellow
guard let img = UIImage(named: "pro1") else {
fatalError("Need an image!")
}
// create the image view
let imgView = UIImageView()
imgView.contentMode = .scaleToFill
imgView.image = img
mainStackView.axis = .horizontal
bottomLabelsStack.axis = .horizontal
bottomLabelsStack.distribution = .fillEqually
// add views to the main stack view
mainStackView.addArrangedSubview(myView)
mainStackView.addArrangedSubview(imgView)
// add main stack view and bottom labels stack view to view
mainStackView.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(mainStackView)
bottomLabelsStack.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(bottomLabelsStack)
let g = view.safeAreaLayoutGuide
NSLayoutConstraint.activate([
// constrain Top/Leading/Trailing
mainStackView.topAnchor.constraint(equalTo: g.topAnchor, constant: 20.0),
mainStackView.leadingAnchor.constraint(equalTo: g.leadingAnchor, constant: 20.0),
//mainStackView.trailingAnchor.constraint(equalTo: g.trailingAnchor, constant: -20.0),
// we want the image view to be 270 x 270
imgView.widthAnchor.constraint(equalToConstant: 270.0),
imgView.heightAnchor.constraint(equalTo: imgView.widthAnchor),
// constrain the bottom lables to the bottom of the main stack view
// same width as the image view
// aligned trailing
bottomLabelsStack.topAnchor.constraint(equalTo: mainStackView.bottomAnchor),
bottomLabelsStack.trailingAnchor.constraint(equalTo: mainStackView.trailingAnchor),
bottomLabelsStack.widthAnchor.constraint(equalTo: imgView.widthAnchor),
])
// setup the left-side custom view
myView.titleText = "Gefährdung"
let titles: [String] = [
"keine / gering", "mittlere", "erhöhte", "hohe",
]
let colors: [UIColor] = [
UIColor(red: 0.863, green: 0.894, blue: 0.527, alpha: 1.0),
UIColor(red: 0.942, green: 0.956, blue: 0.767, alpha: 1.0),
UIColor(red: 0.728, green: 0.828, blue: 0.838, alpha: 1.0),
UIColor(red: 0.499, green: 0.706, blue: 0.739, alpha: 1.0),
]
for (c, t) in zip(colors, titles) {
// because we'll be using hitTest in our Custom View
// we don't need to set .isUserInteractionEnabled = true
// create a "color label"
let cl = colorLabel(withColor: c, title: t, titleColor: .black)
// we're limiting the height to 270, so
// let's use a smaller font for the left-side labels
cl.font = .systemFont(ofSize: 12.0, weight: .light)
// create a tap recognizer
let t = UITapGestureRecognizer(target: self, action: #selector(didTapRotatedLeftLabel(_:)))
// add the recognizer to the label
cl.addGestureRecognizer(t)
// add the label to the custom myView
myView.addLabel(cl)
}
// rotate the left-side custom view 90-degrees counter-clockwise
myView.rotateTo(-.pi * 0.5)
// setup the bottom labels
let colorDictionary = [
"Red":UIColor.systemRed,
"Green":UIColor.systemGreen,
"Blue":UIColor.systemBlue,
]
for (myKey,myValue) in colorDictionary {
// bottom labels are not rotated, so we can add tap gesture recognizer directly
// create a "color label"
let cl = colorLabel(withColor: myValue, title: myKey, titleColor: .white)
// let's use a smaller, bold font for the left-side labels
cl.font = .systemFont(ofSize: 12.0, weight: .bold)
// by default, .isUserInteractionEnabled is False for UILabel
// so we must set .isUserInteractionEnabled = true
cl.isUserInteractionEnabled = true
// create a tap recognizer
let t = UITapGestureRecognizer(target: self, action: #selector(didTapBottomLabel(_:)))
// add the recognizer to the label
cl.addGestureRecognizer(t)
bottomLabelsStack.addArrangedSubview(cl)
}
}
#objc func didTapRotatedLeftLabel (_ sender: UITapGestureRecognizer) {
if let v = sender.view as? UILabel {
let title = v.text ?? "label with no text"
print("Tapped Label in Rotated Custom View:", title)
// do something based on the tapped label/view
}
}
#objc func didTapBottomLabel (_ sender: UITapGestureRecognizer) {
if let v = sender.view as? UILabel {
let title = v.text ?? "label with no text"
print("Tapped Bottom Label:", title)
// do something based on the tapped label/view
}
}
func colorLabel(withColor color:UIColor, title:String, titleColor:UIColor) -> UILabel {
let newLabel = PaddedLabel()
newLabel.padding = UIEdgeInsets(top: 6, left: 8, bottom: 6, right: 8)
newLabel.backgroundColor = color
newLabel.text = title
newLabel.textAlignment = .center
newLabel.textColor = titleColor
newLabel.setContentHuggingPriority(.required, for: .vertical)
return newLabel
}
}
class MyCustomView: UIView {
public var titleText: String = "" {
didSet { titleLabel.text = titleText }
}
public func addLabel(_ v: UIView) {
labelsStack.addArrangedSubview(v)
}
public func rotateTo(_ d: Double) {
// get the container view (in this case, it's the outer stack view)
if let v = subviews.first {
// set the rotation transform
if d == 0 {
self.transform = .identity
} else {
self.transform = CGAffineTransform(rotationAngle: d)
}
// remove the container view
v.removeFromSuperview()
// tell it to layout itself
v.setNeedsLayout()
v.layoutIfNeeded()
// get the frame of the container view
// apply the same transform as self
let r = v.frame.applying(self.transform)
wC.isActive = false
hC.isActive = false
// add it back
addSubview(v)
// set self's width and height anchors
// to the width and height of the container
wC = self.widthAnchor.constraint(equalToConstant: r.width)
hC = self.heightAnchor.constraint(equalToConstant: r.height)
guard let sv = v.superview else {
fatalError("no superview")
}
// apply the new constraints
NSLayoutConstraint.activate([
v.centerXAnchor.constraint(equalTo: self.centerXAnchor),
v.centerYAnchor.constraint(equalTo: self.centerYAnchor),
wC,
outerStack.widthAnchor.constraint(equalTo: sv.heightAnchor),
])
}
}
// our subviews
private let outerStack = UIStackView()
private let titleLabel = UILabel()
private let labelsStack = UIStackView()
private var wC: NSLayoutConstraint!
private var hC: NSLayoutConstraint!
override init(frame: CGRect) {
super.init(frame: frame)
commonInit()
}
required init?(coder: NSCoder) {
super.init(coder: coder)
commonInit()
}
private func commonInit() {
// stack views and label properties
outerStack.axis = .vertical
outerStack.distribution = .fillEqually
labelsStack.axis = .horizontal
// let's use .fillProportionally to help fit the labels
labelsStack.distribution = .fillProportionally
titleLabel.textAlignment = .center
titleLabel.backgroundColor = .lightGray
titleLabel.textColor = .white
// add title label and labels stack to outer stack
outerStack.addArrangedSubview(titleLabel)
outerStack.addArrangedSubview(labelsStack)
outerStack.translatesAutoresizingMaskIntoConstraints = false
addSubview(outerStack)
wC = self.widthAnchor.constraint(equalTo: outerStack.widthAnchor)
hC = self.heightAnchor.constraint(equalTo: outerStack.heightAnchor)
NSLayoutConstraint.activate([
outerStack.centerXAnchor.constraint(equalTo: self.centerXAnchor),
outerStack.centerYAnchor.constraint(equalTo: self.centerYAnchor),
wC, hC,
])
}
override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
// convert the point to the labels stack view coordinate space
let pt = labelsStack.convert(point, from: self)
// loop through arranged subviews
for i in 0..<labelsStack.arrangedSubviews.count {
let v = labelsStack.arrangedSubviews[i]
// if converted point is inside subview
if v.frame.contains(pt) {
return v
}
}
return super.hitTest(point, with: event)
}
}
class PaddedLabel: UILabel {
var padding: UIEdgeInsets = .zero
override func drawText(in rect: CGRect) {
super.drawText(in: rect.inset(by: padding))
}
override var intrinsicContentSize : CGSize {
let sz = super.intrinsicContentSize
return CGSize(width: sz.width + padding.left + padding.right, height: sz.height + padding.top + padding.bottom)
}
}
The problem is with the the stackView's height. Once the label is rotated, the stackview's height is same as before and the tap gestures will only work within stackview's bounds.
I have checked it by changing the height of the stackview at the transform and observed tap gestures are working fine with the rotated label but with the part of it inside the stackview.
Now the problem is that you have to keep the bounds of the label inside the stackview either by changing it axis(again a new problem as need to handle the layout with it) or you have to handle it without the stackview.
You can check the observation by clicking the part of rotated label inside stackview and outside stackview.
Code to check it:
class ViewController: UIViewController {
var centerLabel = UILabel()
let mainStackView = UIStackView()
var stackViewHeightCons:NSLayoutConstraint?
var stackViewTopsCons:NSLayoutConstraint?
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .systemYellow
mainStackView.axis = .horizontal
mainStackView.alignment = .top
mainStackView.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(mainStackView)
mainStackView.leadingAnchor.constraint(equalTo: view.leadingAnchor).isActive = true
mainStackView.trailingAnchor.constraint(equalTo: view.trailingAnchor).isActive = true
stackViewTopsCons = mainStackView.topAnchor.constraint(equalTo: view.topAnchor, constant: 300)
stackViewTopsCons?.isActive = true
stackViewHeightCons = mainStackView.heightAnchor.constraint(equalToConstant: 30)
stackViewHeightCons?.isActive = true
centerLabel.textAlignment = .center
centerLabel.text = "Let's rotate this label"
centerLabel.backgroundColor = .green
centerLabel.tag = 11
setTapListener(centerLabel)
mainStackView.addArrangedSubview(centerLabel)
// outline the stack view so we can see its frame
mainStackView.layer.borderColor = UIColor.red.cgColor
mainStackView.layer.borderWidth = 1
}
public func setTapListener(_ label: UILabel){
let tapGesture: UITapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(tapGestureMethod(_:)))
tapGesture.numberOfTapsRequired = 1
tapGesture.numberOfTouchesRequired = 1
label.isUserInteractionEnabled = true
label.addGestureRecognizer(tapGesture)
}
#objc func tapGestureMethod(_ gesture: UITapGestureRecognizer) {
print(gesture.view?.tag ?? 0)
var yCor:CGFloat = 300
if centerLabel.transform == .identity {
centerLabel.transform = CGAffineTransform(rotationAngle: -CGFloat.pi / 2)
yCor = mainStackView.frame.origin.y - (centerLabel.frame.size.height/2)
} else {
centerLabel.transform = .identity
}
updateStackViewHeight(topCons: yCor)
}
private func updateStackViewHeight(topCons:CGFloat) {
stackViewTopsCons?.constant = topCons
stackViewHeightCons?.constant = centerLabel.frame.size.height
}
}
Sorry. My assumption was incorrect.
Why are you decided to use Label instead of UIButton (with transparence background color and border line)?
Also you can use UITableView instead of stack & labels
Maybe this documentation will help too (it is written that usually in one view better to keep one gesture recognizer): https://developer.apple.com/documentation/uikit/touches_presses_and_gestures/coordinating_multiple_gesture_recognizers

is there a UIKit equivalent to SwiftUI's zstack?

I'm trying to create something like this. I've been working with SwiftUI recently so I know I could create that by adding an image, text and button (the I'm flexible text is the label for a button/NavigationLink) to a zstack. but I'm looking around trying to see if there's anyway to do that in UIKit. preferably without using storyboards. I'm open to a cocoapods library or whatever if that's what it takes. I've looked around and explored using SwiftUI to create the desired ZStack and then use it in my UIKit with a UIHostingController but because it involves a button/navigationlink. seeing as how the NavigationLink would require the destination to conform to a View, I wanted to ask around before converting even more of my project to swiftui. I was more hoping this project would be for giving me more experience building views in UIKit without storyboards so I'd prefer to do that instead of using SwiftUI. if that's possible I guess.
I've tried searching around but all my google searches involving UIButtons and images just link to posts about setting the image in a UIButton.
since you wanted to get more experience in creating views using UIKit, I've created a view that inherits from UIView that you can reuse. There's quite a lot of code to get the same result in UIKit. The code and output are provided below.
NOTE: Read the comments provided
Code
class ImageCardWithButton: UIView {
lazy var cardImage: UIImageView = {
let image = UIImageView()
image.translatesAutoresizingMaskIntoConstraints = false // To flag that we are using Constraints to set the layout
image.image = UIImage(named: "dog")
image.contentMode = .scaleAspectFill
return image
}()
lazy var gradientView: UIView = {
let view = UIView()
view.translatesAutoresizingMaskIntoConstraints = false // IMPORTANT IF YOU ARE USING CONSTRAINTS INSTEAD OF FRAMES
return view
}()
// VStack equivalent in UIKit
lazy var contentStack: UIStackView = {
let stack = UIStackView()
stack.translatesAutoresizingMaskIntoConstraints = false
stack.axis = .vertical
stack.distribution = .fillProportionally // Setting the distribution to fill based on the content
return stack
}()
lazy var titleLabel: UILabel = {
let label = UILabel()
label.textAlignment = .center
label.numberOfLines = 0 // Setting line number to 0 to allow sentence breaks
label.text = "Let your curiosity do the booking"
label.font = UIFont(name: "Raleway-Semibold", size: 20) // Custom font defined for the project
label.textColor = .white
return label
}()
lazy var cardButton: UIButton = {
let button = UIButton()
button.translatesAutoresizingMaskIntoConstraints = false
button.backgroundColor = .white
button.setTitle("I'm flexible", for: .normal)
button.setTitleColor(.blue, for: .normal)
// button.addTarget(self, action: #selector(someObjcMethod), for: .touchUpInside) <- Adding a touch event and function to invoke
return button
}()
override init(frame: CGRect) {
super.init(frame: frame)
commonInit()
}
required init?(coder: NSCoder) {
super.init(coder: coder)
commonInit()
}
private func commonInit() {
self.addSubview(cardImage) // Adding the subview to the current view. i.e., self
// Setting the corner radius of the view
self.layer.cornerRadius = 10
self.layer.masksToBounds = true
NSLayoutConstraint.activate([
cardImage.leadingAnchor.constraint(equalTo: self.leadingAnchor),
cardImage.trailingAnchor.constraint(equalTo: self.trailingAnchor),
cardImage.topAnchor.constraint(equalTo: self.topAnchor),
cardImage.bottomAnchor.constraint(equalTo: self.bottomAnchor),
])
setupGradientView()
addTextAndButton()
}
private func setupGradientView() {
let height = self.frame.height * 0.9 // Height of the translucent gradient view
self.addSubview(gradientView)
NSLayoutConstraint.activate([
gradientView.leadingAnchor.constraint(equalTo: self.leadingAnchor),
gradientView.trailingAnchor.constraint(equalTo: self.trailingAnchor),
gradientView.bottomAnchor.constraint(equalTo: self.bottomAnchor),
gradientView.heightAnchor.constraint(equalToConstant: height)
])
// Adding the gradient
let colorTop = UIColor.clear
let colorBottom = UIColor.black
let gradientLayer = CAGradientLayer()
gradientLayer.colors = [colorTop.cgColor, colorBottom.cgColor]
gradientLayer.locations = [0.0, 1.0]
gradientLayer.frame = CGRect(
x: 0,
y: self.frame.height - height,
width: self.frame.width,
height: height)
gradientView.layer.insertSublayer(gradientLayer, at:0)
print(self.frame)
}
private func addTextAndButton() {
// Adding the views to the stackview
contentStack.addArrangedSubview(titleLabel)
contentStack.addArrangedSubview(cardButton)
gradientView.addSubview(contentStack)
NSLayoutConstraint.activate([
contentStack.leadingAnchor.constraint(equalTo: self.leadingAnchor, constant: 20),
contentStack.trailingAnchor.constraint(equalTo: self.trailingAnchor, constant: -20), // Negative for leading and bottom constraints
contentStack.bottomAnchor.constraint(equalTo: self.bottomAnchor, constant: -20), // Negative for leading and bottom constraints
cardButton.heightAnchor.constraint(equalToConstant: 60)
])
cardButton.layer.cornerRadius = 30 // Half of the height of the button
}
}
Output
Important pointers
You can create the layout using constraints or frames. In case you are using constraints, it is important to set a views .translatesAutoresizingMaskIntoConstraints to false (You can read the documentation for it).
NSLayoutConstraint.activate([...]) Is used to apply an array of constraints at once. Alternatively, you can use:
cardImage.leadingAnchor.constraint(...)isActivated = true
for individual constraints
Manual layout of the views will sometimes require padding. So for this you will have to use negative or positive values for the padding based on the edge (side) of the view you are in. It's easy to remember to set the value of the padding in the direction of the centre of the view.
E.x., From the leading/left edge, you will need to add a padding of 10 towards the centre of the view or -10 from the right/trailing side towards the centre.

inputAccessoryView, API error? _UIKBCompatInputView? UIViewNoIntrinsicMetric, simple code, can't figure out

Help me in one of the two ways maybe:
How to solve the problem? or
How to understand the error message?
Project summary
So I'm learning about inputAccessoryView by making a tiny project, which has only one UIButton. Tapping the button summons the keyboard with inputAccessoryView which contains 1 UITextField and 1 UIButton. The UITextField in the inputAccessoryView will be the final firstResponder that is responsible for the keyboard with that inputAccessoryView
The error message
API error: <_UIKBCompatInputView: 0x7fcefb418290; frame = (0 0; 0 0); layer = <CALayer: 0x60000295a5e0>> returned 0 width, assuming UIViewNoIntrinsicMetric
The code
is very straightforward as below
The custom UIView is used as inputAccessoryView. It installs 2 UI outlets, and tell responder chain that it canBecomeFirstResponder.
class CustomTextFieldView: UIView {
let doneButton:UIButton = {
let button = UIButton(type: .close)
return button
}()
let textField:UITextField = {
let textField = UITextField()
textField.placeholder = "placeholder"
return textField
}()
required init?(coder: NSCoder) {
super.init(coder: coder)
initSetup()
}
override init(frame:CGRect) {
super.init(frame: frame)
initSetup()
}
convenience init() {
self.init(frame: .zero)
}
func initSetup() {
addSubview(doneButton)
addSubview(textField)
}
func autosizing(to vc: UIViewController) {
frame = CGRect(x: 0, y: 0, width: vc.view.frame.size.width, height: 40)
let totalWidth = frame.size.width - 40
doneButton.frame = CGRect(x: totalWidth * 4 / 5 + 20,
y: 0,
width: totalWidth / 5,
height: frame.size.height)
textField.frame = CGRect(x: 20,
y: 0,
width: totalWidth * 4 / 5,
height: frame.size.height)
}
override var canBecomeFirstResponder: Bool { true }
override var intrinsicContentSize: CGSize {
CGSize(width: 400, height: 40)
} // overriding this variable seems to have no effect.
}
Main VC uses the custom UIView as inputAccessoryView. The UITextField in the inputAccessoryView becomes the real firstResponder in the end, I believe.
class ViewController: UIViewController {
let customView = CustomTextFieldView()
var keyboardShown = false
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
customView.autosizing(to: self)
}
#IBAction func summonKeyboard() {
print("hello")
keyboardShown = true
self.becomeFirstResponder()
customView.textField.becomeFirstResponder()
}
override var canBecomeFirstResponder: Bool { keyboardShown }
override var inputAccessoryView: UIView? {
return customView
}
}
I've seen people on the internet says this error message will go away if I run on a physical phone. I didn't go away when I tried.
I override intrinsicContentSize of the custom view, but it has no effect.
The error message shows twice together when I tap summon.
What "frame" or "layer" does the error message refer to? Does it refer to the custom view's frame and layer?
If we use Debug View Hierarchy we can see that _UIKBCompatInputView is part of the (internal) view hierarchy of the keyboard.
It's not unusual to see constraint errors / warnings with internal views.
Since frame and/or intrinsic content size seem to have no effect, I don't think it can be avoided (nor does it seem to need to be).
As a side note, you can keep the "Done" button round by using auto-layout constraints. Here's an example:
class CustomTextFieldView: UIView {
let textField: UITextField = {
let tf = UITextField()
tf.font = .systemFont(ofSize: 16)
tf.autocorrectionType = .no
tf.returnKeyType = .done
tf.placeholder = "placeholder"
// textField backgroundColor so we can see its frame
tf.backgroundColor = .yellow
return tf
}()
let doneButton:UIButton = {
let button = UIButton(type: .close)
return button
}()
override init(frame: CGRect) {
super.init(frame: frame)
commonInit()
}
required init?(coder: NSCoder) {
super.init(coder: coder)
commonInit()
}
func commonInit() -> Void {
autoresizingMask = [.flexibleHeight, .flexibleWidth]
[doneButton, textField].forEach { v in
v.translatesAutoresizingMaskIntoConstraints = false
addSubview(v)
}
NSLayoutConstraint.activate([
// constrain doneButton
// Trailing: 20-pts from trailing
doneButton.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -20.0),
// Top and Bottom 8-pts from top and bottom
doneButton.topAnchor.constraint(equalTo: topAnchor, constant: 8.0),
doneButton.bottomAnchor.constraint(equalTo: bottomAnchor, constant: -8.0),
// Width equal to default height
// this will keep the button round instead of oval
doneButton.widthAnchor.constraint(equalTo: doneButton.heightAnchor),
// constrain textField
// Leading: 20-pts from leading
textField.leadingAnchor.constraint(equalTo: leadingAnchor, constant: 20.0),
// Trailing: 8-pts from doneButton leading
textField.trailingAnchor.constraint(equalTo: doneButton.leadingAnchor, constant: -8.0),
// vertically centered
textField.centerYAnchor.constraint(equalTo: centerYAnchor),
])
}
}
class CustomTextFieldViewController: UIViewController {
let customView = CustomTextFieldView()
var keyboardShown = false
override func viewDidLoad() {
super.viewDidLoad()
}
#IBAction func summonKeyboard() {
print("hello")
keyboardShown = true
self.becomeFirstResponder()
customView.textField.becomeFirstResponder()
}
override var canBecomeFirstResponder: Bool { keyboardShown }
override var inputAccessoryView: UIView? {
return customView
}
}

How to centre-align views in a stack view, and not stretch any of the views, or the distribution?

I am building a custom longitude/latitude selector. The view looks like:
textfield ° textfield ′ textfield ″ N|S
The components are all in a stack view. I would like the width of the textfields to auto-fit the content. Here is the code that I am using (the actual layout code is not a lot. Most of it is boilerplate):
class DMSLongLatInputView : UIView {
private var degreeTextField: DMSLongLatTextField!
private var minuteTextField: DMSLongLatTextField!
private var secondTextField: DMSLongLatTextField!
var signSelector: UISegmentedControl!
let fontSize: CGFloat = 22
override init(frame: CGRect) {
super.init(frame: frame)
commonInit()
}
required init?(coder: NSCoder) {
super.init(coder: coder)
commonInit()
}
private func commonInit() {
degreeTextField = DMSLongLatTextField()
minuteTextField = DMSLongLatTextField()
secondTextField = DMSLongLatTextField()
signSelector = UISegmentedControl(items: ["N", "S"])
signSelector.selectedSegmentIndex = 0
signSelector.setTitleTextAttributes([.font: UIFont.systemFont(ofSize: fontSize)], for: .normal)
[degreeTextField, minuteTextField, secondTextField].forEach { (tf) in
tf?.font = UIFont.monospacedDigitSystemFont(ofSize: fontSize, weight: .regular)
}
let degreeLabel = UILabel()
degreeLabel.text = "°"
let minuteLabel = UILabel()
minuteLabel.text = "′"
let secondLabel = UILabel()
secondLabel.text = "″"
[degreeLabel, minuteLabel, secondLabel].forEach {
l in l.font = UIFont.systemFont(ofSize: fontSize)
}
let stackView = UIStackView(arrangedSubviews:
[degreeTextField,
degreeLabel,
minuteTextField,
minuteLabel,
secondTextField,
secondLabel,
signSelector
])
stackView.arrangedSubviews.forEach { (v) in
// I was hoping that this would make the widths of the stack view's subviews automatically
// fit the content
v.setContentCompressionResistancePriority(.required, for: .horizontal)
v.setContentHuggingPriority(.required, for: .horizontal)
}
stackView.axis = .horizontal
stackView.alignment = .center
stackView.distribution = .fill
addSubview(stackView)
stackView.topAnchor.constraint(equalTo: self.topAnchor).isActive = true
stackView.bottomAnchor.constraint(equalTo: self.bottomAnchor).isActive = true
stackView.leadingAnchor.constraint(equalTo: self.leadingAnchor).isActive = true
stackView.trailingAnchor.constraint(equalTo: self.trailingAnchor).isActive = true
stackView.translatesAutoresizingMaskIntoConstraints = false
backgroundColor = .clear
}
}
fileprivate class DMSLongLatTextField: UITextField, UITextFieldDelegate {
override init(frame: CGRect) {
super.init(frame: frame)
commonInit()
}
required init?(coder: NSCoder) {
super.init(coder: coder)
commonInit()
}
private func commonInit() {
backgroundColor = .tertiarySystemFill
placeholder = "00"
borderStyle = .none
textAlignment = .right
}
}
This produces:
The first textfield got stretched by a lot, even though I set the content hugging priority to .required. I would like the first textfield to be only as wide as two digits, as that is how wide its placeholder is.
I suspected that this is because I used a wrong distribution, but I tried all the other 4 distributions, but none of them got the result I wanted. For example, .equalSpacing with spacing = 0 gave this result (as seen from the UI hierarchy inspector in the debugger):
Clearly the spacing is not 0! I would like all the subviews to be as close together as they can be, and stay centre-aligned. How can I do that?
You're setting Leading and Trailing on the stack view... in other words, you're telling auto-layout to:
"Fill the width of the screen with the subviews."
Change your constraints to this:
stackView.topAnchor.constraint(equalTo: self.topAnchor).isActive = true
stackView.bottomAnchor.constraint(equalTo: self.bottomAnchor).isActive = true
//stackView.leadingAnchor.constraint(equalTo: self.leadingAnchor).isActive = true
//stackView.trailingAnchor.constraint(equalTo: self.trailingAnchor).isActive = true
stackView.centerXAnchor.constraint(equalTo: self.centerXAnchor).isActive = true
That should horizontally center your stack view and its subviews.

Custom UITextField with UILabel multiline support for error text

I want to create custom UITextField with error label on bottom of it. I want the label to be multiline, I tried numberOfLines = 0. But it is not working.
Here is my snippet for the class
public class MyTextField: UITextField {
private let helperTextLabel: UILabel = {
let label = UILabel()
label.font = UIFont.systemFont(ofSize: 12.0, weight: UIFont.Weight.regular)
label.textColor = helperTextColor
label.numberOfLines = 0
return label
}()
public override init(frame: CGRect) {
super.init(frame: frame)
self.addSubview(errorTextLabel)
}
public required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
self.addSubview(errorTextLabel)
}
public override func layoutSubviews() {
super.layoutSubviews()
errorTextLabel.frame = CGRect(x: bounds.minX, y: bounds.maxY - 20, width: bounds.width, height: 20)
}
public override var intrinsicContentSize: CGSize {
return CGSize(width: 240.0, height: 68.0)
}
public override func sizeThatFits(_ size: CGSize) -> CGSize {
return intrinsicContentSize
}
}
I think the root cause is because I set height to 20, but how can I set the height dynamically based on the errorTextLabel.text value?
You are giving your label a fixed size.
Not using AutoLayout and giving the textfield and label room to expand it's size when needed.
Personally, if creating this particular control, I would create a UIView with a textfield and a label inside a UIStackView. That way if the label is hidden when there is no error the stackview will automatically adjust the height for you. Then when you unhide it, the view will expand to fit both controls.
A basic example:
//: Playground - noun: a place where people can play
import UIKit
import PlaygroundSupport
class LabelledTextView: UIView {
private let label = UILabel()
private let textfield = UITextField()
private let stackView = UIStackView()
override init(frame: CGRect) {
super.init(frame: frame)
backgroundColor = .white
addSubview(stackView)
stackView.translatesAutoresizingMaskIntoConstraints = false
stackView.topAnchor.constraint(equalTo: topAnchor).isActive = true
stackView.leftAnchor.constraint(equalTo: leftAnchor).isActive = true
stackView.rightAnchor.constraint(equalTo: rightAnchor).isActive = true
stackView.bottomAnchor.constraint(equalTo: bottomAnchor).isActive = true
stackView.alignment = .leading
stackView.axis = .vertical
stackView.distribution = .fillEqually
stackView.addArrangedSubview(textfield)
stackView.addArrangedSubview(label)
textfield.placeholder = "Please enter some text"
label.numberOfLines = 0
label.text = "Text did not pass validation, Text did not pass validation, Text did not pass validation, Text did not pass validation"
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
let labelledTextView = LabelledTextView(frame: CGRect(x: 50, y: 300, width: 300, height: 60))
let vc = UIViewController()
vc.view.addSubview(labelledTextView)
labelledTextView.translatesAutoresizingMaskIntoConstraints = false
labelledTextView.topAnchor.constraint(equalTo: vc.view.topAnchor).isActive = true
labelledTextView.leftAnchor.constraint(equalTo: vc.view.leftAnchor).isActive = true
labelledTextView.widthAnchor.constraint(equalToConstant: 300).isActive = true
labelledTextView.heightAnchor.constraint(greaterThanOrEqualToConstant: 60).isActive = true
PlaygroundPage.current.liveView = vc.view
You need to use sizeToFit():
errorTextLabel.sizeToFit()

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