title: How can I change button to 2 buttons onClick in ionic 3
body: <p>I want to create a button which by default shows ‘Add’ text on it and after click it should ’ - 1 +’ by which the user can add or remove items via pressing on it</p>
  
  <p>when the items is 0 it should show Add again rather than showing '- 0 +'</p>
  
  <p><a href="https://i.stack.imgur.com/RtpaJ.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/RtpaJ.jpg" alt=""></a></p>