title: iOS UiTextField: Text wont center vertically
body: <p>I am using the Xcode 9 interface builder to design my UI. 
  To maintain an UI which looks the same on every kind of Screen ranging from iPhone to iPad I use high constraints to the superview a lot (for example a UiTextField has a hight constraint to the superview with a multiplier of 0.04 etc.)</p>
  
  <p>So far this is working very good however I came across one problem I couldnt solve afterall:
  While the placeholder is centering vertically without a problem the text itself is being placed below the vertical center which results in text being cut off:</p>
  
  <p><img src="https://i.stack.imgur.com/XkP05.jpg" alt="Text center vertically"></p>
  
  <p><img src="https://i.stack.imgur.com/D5zKg.jpg" alt="Text top vertically"></p>
  
  <p>I am playing around with the designer since an hour now without any success. Does anyone know if this problem can be solved from within the designer? Beside the custom height the TextField doesnt has any modifications.</p>