title: iOS text input issue: the caret flies in
body: <p>When I type in words, the caret of the textfield flies in.</p>
  
  <p>And I noticed that , this situation only occurs the the first time.
  I think it is a <code>init</code> issue,</p>
  
  <p><a href="https://i.stack.imgur.com/X8S4w.gif" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/X8S4w.gif" alt="bug"></a></p>
  
  <p>If I assign a frame to the caret at first, may be OK.</p>
  
  <p>And i saw the issue on Ever Notes ,too.
  <a href="https://i.stack.imgur.com/pNwPE.gif" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/pNwPE.gif" alt="enter image description here"></a></p>
  
  <p>I think , <code>caretRect(for:)</code> method of <code>UITextInput</code> is related.</p>
  
  <p>How to solve it? Any good ideas?</p>