title: Selecting all the items in UICollectionView iOS, even the cells that are not visible
body: <p>I am in the middle of creating an application where I have a button on a tool bar which selects all the items inside a collection view.</p>
  
  <p>But the problem that I am facing is, when I tap on the button it selects only those items that are visible on the screen. This is due to the CELL REUSE functionality.</p>
  
  <p>Is there any way that I can select all the cells, even those which are not currently visible to the user?</p>
  
  <p>Thanks
  J</p>