Adding views dynamically to UIStackview - swift

Question

I'm trying to add views(or buttons) to UIStackView dynamically.
At first, the UIStackView has no arranged views (vertically), and
after getting from some http response, several views(buttons) are added to UIStackView.
UIStackView is also autolayout to hold a specific area.
I've tried to find dynamic adding example, but failed.
Anyone can show me the examples of adding view onto UIStackView dynamically?

Answer 1

It may help you. Please follow this points:
Add UIScrollView to your UIViewController in storyboard or XIB.
Initiate an NSMutableArray name it arrViews gets server response and adds view in the array.
Initialise UIStackViewpass arrView array in the init method.
After that UIStackView will be added subview of UIScrollView.
Add constraint programmatically to UIStackView. That's it.
if let response = self.serverResponse {
if let body = response.responseBody {
if let view = body.views {
arrViews = createSubViews(view)
}
}
}
let stackView = UIStackView(arrangedSubviews: arrViews)
stackView.translatesAutoresizingMaskIntoConstraints = false
stackView.axis = .vertical
stackView.spacing = 16
stackView.distribution = .fill
self.scrollView.addSubview(stackView)
//constraints
let leading = NSLayoutConstraint(item: stackView, attribute: .leading, relatedBy: .equal, toItem: self.scrollView, attribute: .leading, multiplier: 1.0, constant: 0)
self.scrollView.addConstraint(leading)
let trailing = NSLayoutConstraint(item: stackView, attribute: .trailing, relatedBy: .equal, toItem: self.scrollView, attribute: .trailing, multiplier: 1.0, constant: 0)
self.scrollView.addConstraint(trailing)
let top = NSLayoutConstraint(item: stackView, attribute: .top, relatedBy: .equal, toItem: self.scrollView, attribute: .top, multiplier: 1.0, constant: 0)
self.scrollView.addConstraint(top)
let bottom = NSLayoutConstraint(item: stackView, attribute: .bottom, relatedBy: .equal, toItem: self.scrollView, attribute: .bottom, multiplier: 1.0, constant: 0)
self.scrollView.addConstraint(bottom)
let equalWidth = NSLayoutConstraint(item: stackView, attribute: .width, relatedBy: .equal, toItem: self.scrollView, attribute: .width, multiplier: 1.0, constant: 0)
self.scrollView.addConstraint(equalWidth)
leading.isActive = true
trailing.isActive = true
top.isActive = true
bottom.isActive = true
equalWidth.isActive = true
Hope it will help you. Happy coding :)

Answer 2

I use this code in one of my projects:
let baseFrame = CGRect(origin: .zero, size: CGSize(width: requiredWidth, height: partitionHeight))
for instrument in instruments {
let partitionView = PartitionOnDemand(instrument: instrument, mode: playbackMode, frame: baseFrame, referenceView: partitionsAnimator)
partitionsStackView.addArrangedSubview(partitionView)
let tab = InstrumentInfoTabContainer.instantiate(with: instrument) {
self.focus(on: instrument)
}
tabsStackView.addArrangedSubview(tab)
}

Answer 3

While trying with answers, I happend to find how to work it.
class ViewController: UIViewController {
#IBOutlet weak var stack: UIStackView!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
#IBAction func onBtn_Create(_ sender: Any) {
createButton("new button ...")
}
#IBAction func onBtn_Delete(_ sender: Any) {
if let v = stack.arrangedSubviews.last {
stack.removeArrangedSubview(v)
v.removeFromSuperview()
}
}
func createButton(_ title: String) {
let button = UIButton()
button.frame = CGRect(x: 0, y: 0, width: 100, height: 100)
button.backgroundColor = UIColor.blue
button.setTitle(title, for: .normal)
button.addTarget(self, action: #selector(buttonAction), for: .touchUpInside)
stack.addArrangedSubview(button)
}
#objc func buttonAction(sender: UIButton!) {
print("Button tapped")
}
}
And, I anchored to UIStackView, Trailing=0, Leading=0, Top=0, Bottom=8 to TextView.Top
The subviews inside it are intact without any constraints.
Thank you.