title: isExclusiveTouch not working on a custom UIView
body: <p>I have a view containing two subviews : a bar made of a custom view on top of a UIPageViewController</p>
  
  <p>I want to avoid the user being able to touch the bar and the pageView at the same time (the bar controls the page view and touching them at the same time can cause crashes)</p>
  
  <p>what I did is to set the bar view isExclusiveTouch property to true.</p>
  
  <pre><code>override func awakeFromNib() {
      [...]
      isExclusiveTouch = true
  }
  </code></pre>
  
  <p>The <a href="https://developer.apple.com/library/content/documentation/EventHandling/Conceptual/EventHandlingiPhoneOS/multitouch_background/multitouch_background.html" rel="nofollow noreferrer">documentation</a> says that if a view isExclusiveTouch property is set to true, other views in the same window should not be able to receive any touch event. Yet I am able to touch and scroll in the page view while touching the bar. </p>
  
  <p>On another screen I have multiple switches made of custom views, I want to avoid multiple switches being touch at the same time so I also put their isExclusiveTouch to true, but still can touch two of them at the same time.</p>
  
  <p>I am missing the isExclusiveTouch is not working at all?</p>