Swift UIKIT components do not show on a working view

Question

I'm turning my hand from years of Java / C++ / C to trying to learn Swift and how to develop on Apple.

I've tried a lot of tutorials and for what I want to achieve I need to use a splitview controller.

I need to have a few different detail views and can't work out how to do this via storyboard and thought I'd try to do it with code.

Following a tutorial and several google searches Im hitting a problem which I realise is me being a newbiee and ask for your help.

To keep things simple I created a test viewcontroller class and set it in the storyboard no problem.

import UIKit;

class tesctVC : UIViewController {
    var scoreLabel: UILabel!
    
    override func loadView() {
        view = UIView()
        view.backgroundColor = .white
        
        scoreLabel = UILabel()
        scoreLabel.translatesAutoresizingMaskIntoConstraints = false
        scoreLabel.textAlignment = .right
        scoreLabel.text = "Score: 0"
        view.addSubview(scoreLabel)
        // more code to come!
    }
}

When I change to background color it shows as expected.

But when I try to add anything else, I've tried UILabels, UIButtons etc, they do not show.

Would you please give me some pointers?

You need to set constraints for the label. Leading, trailing, top and bottom. Or width, height and alignment — cora, Nov 26 '20 at 15:49
https://stackoverflow.com/questions/26180822/how-to-add-constraints-programmatically-using-swift — cora, Nov 26 '20 at 15:51

score 0 · Answer 1 · answered Nov 26 '20 at 17:50

Thanks again. I thought this may help others.

This is still WIP but shows some hints I found along the way.

I want to add a bunch of labels & buttons etc.

This in so far as is written does the job. It needs more formatting and so on.

The extension is needed to set a stacks background color. I think someone explained its because a StackView is not a drawable object.

extension UIStackView {
    func addBackground(color: UIColor) {
        let subView = UIView(frame: bounds)
        subView.backgroundColor = color
        subView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
        insertSubview(subView, at: 0)
    }
}


class DetailViewController: UIViewController , UIWebViewDelegate {


    
    var usernameEdt: UITextField!
    var passwordEdt: UITextField!
    var statusLabel: UILabel!
    var LogubButton = UIButton()
           
    
    // Draw the login page
    func loginPage() {
      
        // Create the top level statck
        let stackView = UIStackView()
        stackView.addBackground(color: .white)
        stackView.axis = .vertical
        stackView.alignment = .center // .leading .firstBaseline .center .trailing .lastBaseline
        stackView.distribution = .fillEqually // .fillEqually .fillProportionally .equalSpacing .equalCentering
        
        // Add the title
        let label = UILabel()
        label.frame = CGRect(x: 150, y: 200, width: 200, height: 20)
        label.font = UIFont.boldSystemFont(ofSize: 20.0)
        label.text = "Login Details"
        label.textColor = .blue
        
        stackView.addArrangedSubview(label)
        
   
        // Add Username
        usernameEdt = UITextField()
        usernameEdt.placeholder = "Enter Your Username"
       
        stackView.addArrangedSubview(usernameEdt)
       
        
        // Add Password
        passwordEdt = UITextField()
        passwordEdt.placeholder = "Enter Your Password"
        stackView.addArrangedSubview(passwordEdt)
 
        
        self.view = stackView
    }

Thanks Jeff

Swift UIKIT components do not show on a working view

1 Answers1