title: UIStackView Spacing - Don't push to top and bottom anchors
body: <p>I am trying to distribute some nested stack views and I think I'm missing a property to help me align the various views the way I want them.</p>
  
  <p>Here's the current output:</p>
  
  <p><a href="https://i.stack.imgur.com/QF9YZ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/QF9YZ.png" alt="enter image description here"></a></p>
  
  <p>The issue with this is that the two arranged subviews that are added to each column (a stackview), are distributed so that the first subview aligns to the top, and the second subview aligns to the bottom (leaving a variable space in between them).</p>
  
  <p>But here's what I am hoping for - always a fixed space (say 10 px) in between the first and second arranged subview in each column, and the extra space below the second arranged subview is just left to be what it needs to be.</p>
  
  <p><a href="https://i.stack.imgur.com/6fhUv.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/6fhUv.png" alt="enter image description here"></a></p>
  
  <p>The view is arranged as follows:</p>
  
  <p><code>outerStackView</code> = the green view: (20px off top, 64px off left, 20px off bottom, 
  64px off right - present in both screenshots but only highlighted on the top one) with properties:</p>
  
  <pre><code>outerStackView.axis = .Horizontal
  outerStackView.distribution = .FillEqually
  outerStackView.spacing = 10
  </code></pre>
  
  <p><code>leftStackView</code>, <code>middleStackView</code>, <code>rightStackView</code> added to the <code>outerStackView</code> each with properties:</p>
  
  <pre><code>columnStackView.axis = .Vertical
  columnStackView.distribution = .Fill
  columnStackView.alignment = UIStackViewAlignment.Top
  columnStackView.spacing = 10
  </code></pre>
  
  <p>Then each column has 2 stackViews inside of it, represented by the darker gray box directly around the red and blue boxes. With properties:</p>
  
  <pre><code>redBlueStackView.axis = .Horizontal
  redBlueStackView.distribution = .FillProportionally
  redBlueStackView.alignment = UIStackViewAlignment.Top
  redBlueStackView.spacing = 4
  </code></pre>