rectangular region that restricts where the handle may move. The region should be defined in
this view&rsquo;s coordinates. For instance, to constrain the handle in the Y direction with a UIView of size 100x100,
use <code>CGRect(x: 50, y: 0, width: 1, height: 100)</code></p>

                      </div>
                      <div class="declaration">
                        <h4>Declaration</h4>
                        <div class="language">
                          <p class="aside-title">Swift</p>
       