title: How to recreate the IOS calculator layout using auto layout
body: <p>I am trying to recreate the calculator app layout in my app. My problem is that I can't get auto layout to work right. So I have a label at the top and 19 buttons (0 is bigger than the other ones).  </p>
  
  <p>What I did:<br>
  For label, I control + drag from the label to the top and margins (<code>Leading Space to Container Margin</code>, <code>Top Space to Top Layout Guide</code>, <code>Trailing Space to Container Margin</code>). Then for the bottom part warning, I went and <code>Update Frame</code>. This works.  </p>
  
  <p>For the buttons I set <code>Equal Heights</code> for all of them and <code>Equal Widths</code> for all of them expect the bigger button (0). For the buttons from the upper part again I control drag from them to the label and set <code>Vertical</code> (I don't want any space between them, and I don't know what to set here). For the buttons from the right I control + drag and set <code>Trailing Space to Container Margin</code>. For the bottom ones I control + drag and set <code>Bottom Space to Bottom Layout Guide</code>. Same thing for the left buttons.  </p>
  
  <p>I am not sure what to do for the buttons in the middle. I don't want any space between any control, but from the tutorials I didn't saw how to control drag from one control to another and tell it to not be space between them.  </p>
  
  <p>Any suggestions how to fix my alignment issues ? I always get: <code>Need Constraint for: X/Y Position</code> errors.</p>