Can't get StackView to view items properly - ios

I'm trying to add 4 items to a UIStackView, this 4 Items are all a simple square UIView, I added them all to a UIStackView but they won't stay square, it's like the UIStackView squeezes them or something. I tried setting the UIStackView to be the same height of the items, and set it's width to be the height of the items * 4 so I can try and get 1:1 ratio, but nothing worked for me.
The UIView is a simple UIView with background color. I tried to set it's widthAnchor and heightAnchor to 50, but I know the UIStackView has it's own way to size the items in it.
I don't really know what to do about this.
This is my UIStackView setup and constraints:
Setup:
private lazy var optionButtonStack: UIStackView = {
let stack = UIStackView(arrangedSubviews: [self.optionButton1, self.optionButton2, self.optionButton3, self.optionButton4])
stack.translatesAutoresizingMaskIntoConstraints = false
stack.distribution = .fillEqually
stack.axis = .horizontal
stack.spacing = 2.5
return stack
}()
Constraints:
private func setupOptionButtonStack() {
addSubview(optionButtonStack)
NSLayoutConstraint.activate([
optionButtonStack.heightAnchor.constraint(equalToConstant: 50),
optionButtonStack.widthAnchor.constraint(equalToConstant: 200),
optionButtonStack.centerXAnchor.constraint(equalTo: self.centerXAnchor),
optionButtonStack.bottomAnchor.constraint(equalTo: buyNowButton.topAnchor, constant: -8),
])
}
This is the UIView in case this is needed:
private let optionButton1: UIView = {
let view = UIView()
view.backgroundColor = .appBlue
view.translatesAutoresizingMaskIntoConstraints = false
view.widthAnchor.constraint(equalToConstant: 50).isActive = true
view.heightAnchor.constraint(equalToConstant: 50).isActive = true
view.tag = 1
return view
}()

Give the button view a single constraint setting its width equal to its height:
view.widthAnchor.constraint(equalTo: view.heightAnchor).isActive = true
and set the stack view alignment at center.

Related

UIImageView cuts inside UIScrollView

I'm trying to create UIScrollView With UIStackView that contains multiple UIImageView with this code:
let stackView = UIStackView(frame: .zero)
scrollView.translatesAutoresizingMaskIntoConstraints = false
scrollView.backgroundColor = .green
scrollView.showsHorizontalScrollIndicator = false
scrollView.delegate = self
self.view.addSubview(scrollView)
scrollView.anchor(top: textSV.bottomAnchor, leading: self.view.safeAreaLayoutGuide.leadingAnchor, bottom: anotherView?.topAnchor, trailing: self.view.safeAreaLayoutGuide.trailingAnchor)
scrollView.widthAnchor.constraint(equalToConstant: UIScreen.main.bounds.width).isActive = true
scrollView.contentInsetAdjustmentBehavior = .never
stackView.translatesAutoresizingMaskIntoConstraints = false
stackView.distribution = .equalSpacing
stackView.spacing = 0
scrollView.addSubview(stackView)
stackView.fillSuperview()
for _ in 1...8 {
let pageView = UIImageView(image: UIImage(named: "iphone12mockup"))
pageView.clipsToBounds = true
pageView.contentMode = .scaleAspectFit
pageView.translatesAutoresizingMaskIntoConstraints = false
stackView.addArrangedSubview(pageView)
pageView.anchor(top: stackView.topAnchor, leading: nil, bottom: stackView.bottomAnchor, trailing: nil)
}
The problem is that the UIImageView does not resize to scaleAspectFit and it looks like this(Can't see full image):
EDIT
let img = UIImage(named: "iphone12mockup")
let width = img?.size.width
let pageView = UIImageView(image: img)
pageView.clipsToBounds = true
pageView.contentMode = .scaleAspectFit
pageView.translatesAutoresizingMaskIntoConstraints = false
stackView.addArrangedSubview(pageView)
pageView.anchor(top: stackView.topAnchor, leading: nil, bottom: stackView.bottomAnchor, trailing: nil)
pageView.widthAnchor.constraint(equalToConstant: width!).isActive = true
You want to make use of the scroll view's Content and Frame Layout Guides...
constrain all 4 sides of the stack view to the scroll view's Content Layout Guide
constrain the stack view's Height to the scroll view's Frame Layout Guide
for each image view you add to the stack view:
constrain the image view's Width to the scroll view's Frame Layout Guide
Here is a complete example:
class ViewController: UIViewController, UIScrollViewDelegate {
override func viewDidLoad() {
super.viewDidLoad()
// just trying to include what you've shown
let textSV = UILabel()
textSV.backgroundColor = .yellow
textSV.text = "textSV"
textSV.textAlignment = .center
let anotherView = UILabel()
anotherView.backgroundColor = .cyan
anotherView.text = "anotherView"
anotherView.textAlignment = .center
[textSV, anotherView].forEach {
$0.translatesAutoresizingMaskIntoConstraints = false
view.addSubview($0)
}
// respect safe area
let safeG = view.safeAreaLayoutGuide
NSLayoutConstraint.activate([
textSV.topAnchor.constraint(equalTo: safeG.topAnchor),
textSV.leadingAnchor.constraint(equalTo: safeG.leadingAnchor),
textSV.trailingAnchor.constraint(equalTo: safeG.trailingAnchor),
textSV.heightAnchor.constraint(equalToConstant: 60.0),
anotherView.leadingAnchor.constraint(equalTo: safeG.leadingAnchor),
anotherView.trailingAnchor.constraint(equalTo: safeG.trailingAnchor),
anotherView.bottomAnchor.constraint(equalTo: safeG.bottomAnchor),
anotherView.heightAnchor.constraint(equalToConstant: 60.0),
])
let scrollView = UIScrollView()
scrollView.translatesAutoresizingMaskIntoConstraints = false
scrollView.backgroundColor = .green
scrollView.showsHorizontalScrollIndicator = false
scrollView.delegate = self
view.addSubview(scrollView)
// use a stack view to hold and arrange the scrollView's subviews
let stackView = UIStackView()
stackView.translatesAutoresizingMaskIntoConstraints = false
// add the stackView to the scrollView
scrollView.addSubview(stackView)
// use scrollView's Content Layout Guide to define scrollable content
let layoutG = scrollView.contentLayoutGuide
// use scrollView's Frame Layout Guide to define content height (since you want horizontal scrolling)
let frameG = scrollView.frameLayoutGuide
NSLayoutConstraint.activate([
// constrain scrollView Top to textSV Bottom
scrollView.topAnchor.constraint(equalTo: textSV.bottomAnchor),
// constrain scrollView Leading/Trailing to safe area
scrollView.leadingAnchor.constraint(equalTo: safeG.leadingAnchor),
scrollView.trailingAnchor.constraint(equalTo: safeG.trailingAnchor),
// constrain scrollView Bottom to anotherView Top
scrollView.bottomAnchor.constraint(equalTo: anotherView.topAnchor),
// constrain all 4 sides of the stackView to scrollView's Content Layout Guide
stackView.topAnchor.constraint(equalTo: layoutG.topAnchor),
stackView.bottomAnchor.constraint(equalTo: layoutG.bottomAnchor),
stackView.leadingAnchor.constraint(equalTo: layoutG.leadingAnchor),
stackView.trailingAnchor.constraint(equalTo: layoutG.trailingAnchor),
// constrain stackView's height to scrollView's Frame Layout Guide height
stackView.heightAnchor.constraint(equalTo: frameG.heightAnchor),
])
// add imageViews to the stack view
for _ in 1...8 {
let pageView = UIImageView(image: UIImage(named: "iphone12mockup"))
//let pageView = UIImageView(image: UIImage(named: "sample"))
// set image view background color so you can
// see its frame (since the image will be aspect-fit scaled)
pageView.backgroundColor = .systemYellow
pageView.contentMode = .scaleAspectFit
// add it to the stack view
stackView.addArrangedSubview(pageView)
// constrain its Width to scrollView's Frame Layout Guide Width
pageView.widthAnchor.constraint(equalTo: frameG.widthAnchor).isActive = true
}
}
}
It will look like this on startup (on an iPhone 8):
and after scrolling a little to the right:
Note that since you want the image view set to Aspect Fit, I gave the "pageView" image views a background color of .systemYellow so you can see that the imageView frame fills the scroll view frame width and height.
Edit -- if you want the images to be proportional to their height, without "empty space on the sides," you need to set the image view width constraint proportional to its height, based on the image size.
Replace the "add image views" loop with this:
// add imageViews to the stack view
for _ in 1...8 {
guard let img = UIImage(named: "iphone12mockup") else {
fatalError("Could not load image!")
}
let pageView = UIImageView()
pageView.image = img
pageView.contentMode = .scaleToFill
// add it to the stack view
stackView.addArrangedSubview(pageView)
// constrain its Width proportional to the image height
pageView.widthAnchor.constraint(equalTo: pageView.heightAnchor, multiplier: img.size.width / img.size.height).isActive = true
}
and the output will be:
and after scrolling a little to the right:

How can I change height of the view which is present in StackView

I have a custom UIView using for Custom UITabBar whose height is fixed 50 and I am adding a stackview for each button but I need middle button height should be more.
let view: UIView = views[3]
view.heightAnchor.equalToConstant(100.0).isActive = true
let stackView: UIStackView = UIStackView(arrangedSubviews: [views])
stackView.translatesAutoresizingMaskIntoConstraints = false
stackView.axis = .horizontal
stackView.distribution = .fillEqually
addSubview(stackView)
stackView.topAnchor.constraint(equalTo: topAnchor).isActive = true
stackView.bottomAnchor.constraint(equalTo: bottomAnchor).isActive = true
stackView.trailingAnchor.constraint(equalTo: trailingAnchor).isActive = true
stackView.leadingAnchor.constraint(equalTo: leadingAnchor).isActive = true
How can I change the height of a particular view inside the stackView?
I may not understand your problem but you can change anyviews height using constraints as you have already done.
It is same when the view is subview of a stackview. Stackview updates it's size to satisfy its constraint.
You have to have a reference to height constraint of the view inside stackview.
Then you can change it whenever need to.
Also it would be nice to set stackviews alignment property to have desired look.
let heightConstraint = view.heightAnchor.equalToConstant(100.0)
heightConstraint.isActive = true
.
.
.
heightConstraint.constant = 150
You want to change the Alignment property of the stack view...
Assuming 5 views, each with a height constraint of 60, and you want the 4th view (views[3]) to have a height of 100.
StackView Alignment Top:
StackView Alignment Center:
StackView Alignment Bottom:

How to increase UIView height which contains UIStackView

I have a custom view which contains a label, label can have multiple line text. So i have added that label inside a UIStackView, now my StackView height is increasing but the custom view height doesn't increases. I haven't added bottom constraint on my StackView. What should I do so that my CustomView height also increases with the StackView.
let myView = Bundle.main.loadNibNamed("TestView", owner: nil, options: nil)![0] as! TestView
myView.lbl.text = "sdvhjvhsdjkvhsjkdvhsjdvhsdjkvhsdjkvhsdjkvhsjdvhsjdvhsjdvhsjdvhsjdvhsjdvhsjdvhsdjvhsdjvhsdjvhsdjvhsdjvhsjdvhsdjvhsdjvhsjdvhsdjvhsjdvhsdjvhsdjvhsdjvhsjdv"
myView.lbl.sizeToFit()
myView.frame = CGRect(x: 10, y: 100, width: UIScreen.main.bounds.width, height: myView.frame.size.height)
myView.setNeedsLayout()
myView.layoutIfNeeded()
self.view.addSubview(myView)
I want to increase my custom view height as per my stackview height.
Please help.
Example of stackView constraints with its superview.
Also superview should not have constraints for its height.
You should set the top and bottom anchors of your custom view to be constrained to the top and bottom anchors of your stackview. As your stackView grows, it will push that bottom margin along. Here's a programmatic example:
//: A UIKit based Playground for presenting user interface
import UIKit
import PlaygroundSupport
class MyViewController : UIViewController {
private lazy var stackView = UIStackView()
private lazy var addLabelButton = UIButton(type: .system)
override func loadView() {
let view = UIView()
view.backgroundColor = .white
let stackViewContainer = UIView(frame: view.bounds)
stackViewContainer.backgroundColor = .yellow
stackViewContainer.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(stackViewContainer)
stackView.translatesAutoresizingMaskIntoConstraints = false
stackView.axis = .vertical
addLabelButton.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(addLabelButton)
stackViewContainer.addSubview(stackView)
NSLayoutConstraint.activate([
// Container constrained to three edges of its superview (fourth edge will grow as the stackview grows
stackViewContainer.leadingAnchor.constraint(equalTo: view.leadingAnchor),
stackViewContainer.trailingAnchor.constraint(equalTo: view.trailingAnchor),
stackViewContainer.topAnchor.constraint(equalTo: view.topAnchor),
// stackView constraints - stackView is constrained to the
// for corners of its contaier, with margins
{
// Stackview has a height of 0 when no arranged subviews have been added.
let heightConstraint = stackView.heightAnchor.constraint(equalToConstant: 0)
heightConstraint.priority = .defaultLow
return heightConstraint
}(),
stackView.topAnchor.constraint(equalTo: stackViewContainer.topAnchor, constant: 8),
stackView.leadingAnchor.constraint(equalTo: stackViewContainer.leadingAnchor, constant: 8),
stackView.trailingAnchor.constraint(equalTo: stackViewContainer.trailingAnchor, constant: -8),
stackView.bottomAnchor.constraint(equalTo: stackViewContainer.bottomAnchor, constant: -8),
// button constraints
addLabelButton.topAnchor.constraint(equalTo: stackViewContainer.bottomAnchor, constant: 8),
addLabelButton.centerXAnchor.constraint(equalTo: stackViewContainer.centerXAnchor)
])
addLabelButton.setTitle("New Label", for: .normal)
addLabelButton.addTarget(self, action: #selector(addLabel(sender:)), for: .touchUpInside)
self.view = view
}
private(set) var labelCount = 0
#objc func addLabel(sender: AnyObject?) {
let label = UILabel()
label.text = "Label #\(labelCount)"
labelCount += 1
stackView.addArrangedSubview(label)
}
}
// Present the view controller in the Live View window
PlaygroundPage.current.liveView = MyViewController()
Note that when the UIStackView is empty, its height is not well defined. That is why I set its heightAnchor constraint to 0 with a low priority.
First of all you should add bottom constraint on your UIStackView. This will help auto layout in determining the run time size of UIStackView.
Now create instance of your custom UIView but do not set it's frame and add it to UIStackView. Make sure you Custom UiView has all the constraints set for auto layout to determine it's run time frame.
This will increase height of both UIView and UIStackView based on content of UIView elements.
For more details you can follow my detailed answer on this at https://stackoverflow.com/a/57954517/3339966

UIStackView container view height based on subviews

Here is my simple example. I have 1 vertical stack view with 1 subview. I want that subviews height to be based on the intrinsic height of the label within it, so that I can maintain a dynamic height for the entire stack view. How can this be done? Thanks
I think you did it right. But here is the keys:
Don't set height for stackView.
Set label top, bottom, left, trailing constraint to view.
Run. It should be okay on simulator.
If you found label's height seems not wrapping (neither both on storyboard or simulator), then change label's Vertical Content Hugging Priority to 750.
Try this code:
class DyanmicTextLabelViewController: UIViewController {
private var didAddConstraint = false
private let label: UILabel = {
let view = UILabel()
view.translatesAutoresizingMaskIntoConstraints = false
view.setContentHuggingPriority(.required, for: .vertical)
view.setContentCompressionResistancePriority(.required, for: .vertical)
view.text = "Layout anchors let you create constraints in an easy-to-read, compact format. They expose a number of methods for creating different types of constraints, as shown in Listing 13-1."
view.numberOfLines = 0
return view
}()
private lazy var container: UIView = {
let view = UIView()
view.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(label)
view.backgroundColor = .red
return view
}()
private lazy var stackview : UIStackView = {
let view = UIStackView()
view.translatesAutoresizingMaskIntoConstraints = false
view.axis = .horizontal
view.distribution = .fill
view.addArrangedSubview(container)
return view
}()
override func loadView() {
super.loadView()
view.addSubview(stackview)
view.setNeedsUpdateConstraints()
view.backgroundColor = .white
}
override func updateViewConstraints() {
super.updateViewConstraints()
if didAddConstraint == false {
didAddConstraint = true
// stackview constraints
stackview.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
let topAnchor = stackview.topAnchor.constraint(equalTo: view.topAnchor)
topAnchor.constant = 20
topAnchor.isActive = true
stackview.rightAnchor.constraint(equalTo: view.rightAnchor).isActive = true
// label constraint
// example for giving label a left padding
let labelLeft = label.leftAnchor.constraint(equalTo: container.leftAnchor)
labelLeft.constant = 16.0
labelLeft.isActive = true
label.topAnchor.constraint(equalTo: container.topAnchor).isActive = true
label.rightAnchor.constraint(equalTo: container.rightAnchor).isActive = true
label.bottomAnchor.constraint(equalTo: container.bottomAnchor).isActive = true
}
}
}
The important part here is the initialization of stackview, label & constraint set on label
label initialization
private let label: UILabel = {
let view = UILabel()
view.translatesAutoresizingMaskIntoConstraints = false
view.setContentHuggingPriority(.required, for: .vertical)
view.setContentCompressionResistancePriority(.required, for: .vertical)
view.text = "Layout anchors let you create constraints in an easy-to-read, compact format. They expose a number of methods for creating different types of constraints, as shown in Listing 13-1."
view.numberOfLines = 0
return view
}()
stackview initialization
private lazy var stackview : UIStackView = {
let view = UIStackView()
view.translatesAutoresizingMaskIntoConstraints = false
view.axis = .horizontal
view.distribution = .fill
view.addArrangedSubview(container)
return view
}()
label constraint
// label constraint
// example for giving label a left padding
let labelLeft = label.leftAnchor.constraint(equalTo: container.leftAnchor)
labelLeft.constant = 16.0
labelLeft.isActive = true
label.topAnchor.constraint(equalTo: container.topAnchor).isActive = true
label.rightAnchor.constraint(equalTo: container.rightAnchor).isActive = true
label.bottomAnchor.constraint(equalTo: container.bottomAnchor).isActive = true
This settings could be easily translated to storyboard.

Stackview inside Other stackview width issue

I have an Stackview created in IB and it has Vertical orientation. This stackview has equal width to parent view.
Now I am created a Stackview programmatically for example
let stackViewHorizontal = UIStackView()
stackViewHorizontal.axis = UILayoutConstraintAxis.horizontal
stackViewHorizontal.distribution = UIStackViewDistribution.fillEqually
stackViewHorizontal.alignment = UIStackViewAlignment.leading
stackViewHorizontal.spacing = 8
stackViewHorizontal.translatesAutoresizingMaskIntoConstraints = false
stackViewHorizontal.leadingAnchor.constraint(equalTo: mainStackView.leadingAnchor,constant:0)
stackViewHorizontal.trailingAnchor.constraint(equalTo: mainStackView.trailingAnchor,constant:0)
Here mainStackView is a stackview which is created Via IB.and stackviewHorizontal is a stackview that is created programatically.
I am putting to UILabels inside stackViewHorizontal. I expected this will expand to full length and each UiLabel will take 50% of the screen in width since stackview has horizontal axis and distribution is fillEqually.
But I am having a UiLabels next to eachother horizontally. but not taking full width of screen
What I am doing wrong please notify?
Activate constraints, also give it a height:
stackViewHorizontal.leadingAnchor.constraint(equalTo: mainStackView.leadingAnchor,constant:0).isActive = true
stackViewHorizontal.trailingAnchor.constraint(equalTo: mainStackView.trailingAnchor,constant:0).isActive = true
OR
NSLayoutConstraint.activate([
stackViewHorizontal.leadingAnchor.constraint(equalTo: mainStackView.leadingAnchor,constant:0),
stackViewHorizontal.trailingAnchor.constraint(equalTo: mainStackView.trailingAnchor,constant:0)
])
//
let stackViewHorizontal = UIStackView()
stackViewHorizontal.axis = UILayoutConstraintAxis.horizontal
stackViewHorizontal.distribution = UIStackViewDistribution.fillEqually
stackViewHorizontal.alignment = UIStackViewAlignment.leading
stackViewHorizontal.spacing = 8
self.view.addSubview(stackViewHorizontal) //// add it here
stackViewHorizontal.translatesAutoresizingMaskIntoConstraints = false
stackViewHorizontal.leadingAnchor.constraint(equalTo: mainStackView.leadingAnchor, constant: 0).isActive = true
stackViewHorizontal.trailingAnchor.constraint(equalTo: mainStackView.trailingAnchor, constant: 0).isActive = true

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