title: Swift: UIStackView height is always 0 despite adding elements
body: <p>I have this stack view, it contains one ImageView:<br />
  <a href="https://i.stack.imgur.com/ViYsJ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ViYsJ.png" alt="enter image description here" /></a>
  If I print its height, I always get 0:</p>
  <pre><code>  print(&quot;movieDetailsStackView!.bounds.height: &quot;,movieDetailsStackView!.bounds.height ) // 0
      print(&quot;movieDetailsStackView!.frame.height: &quot;,movieDetailsStackView!.frame.height ) // 0
  </code></pre>
  <p>This is how it's created:</p>
  <pre><code>func createMovieDetailsStackView () {
      /******************/
      // Add movie image
      /*****************/
      let movieImageViewHeight = 300.00
      let movieImageViewWidth = 20.00
      movieImageView = UIImageView(frame: CGRect(x: 0, y: 0, width: movieImageViewWidth, height: movieImageViewHeight));
      movieImageView!.layer.borderWidth = 10
      movieImageView!.layer.borderColor = UIColor.red.cgColor
      /******************/
      var arrangedSubviews = [UIView]()
      arrangedSubviews.append(movieImageView!)
      
      movieDetailsStackView = UIStackView(arrangedSubviews: arrangedSubviews)
      
      movieDetailsStackView!.translatesAutoresizingMaskIntoConstraints = false
      movieDetailsStackView!.distribution = .fillProportionally
      movieDetailsStackView!.axis = .horizontal
      movieDetailsStackView!.spacing = 8
  
      self.view.addSubview(movieDetailsStackView!)
  
      movieDetailsStackView!.topAnchor.constraint(equalTo: self.view.topAnchor, constant:70).isActive = true
      movieDetailsStackView!.leftAnchor.constraint(equalTo: self.view.leftAnchor, constant: 0).isActive = true
      movieDetailsStackView!.rightAnchor.constraint(equalTo: self.view.rightAnchor, constant: 0).isActive = true
      
  }
  </code></pre>
  <p>Is there any explanation for this?</p>