title: iOS -- How to scale the UIView with left top point?
body: <p>I want to fix a point (left top point) and scale (zoom out) the UIView according to the point</p>
  
  <p>like this image</p>
  
  <p><a href="https://i.stack.imgur.com/TjsQw.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/TjsQw.jpg" alt="enter image description here"></a></p>
  
  <p>Now I use <code>self.transform = CGAffineTransformMakeScale( 0.7 , 0.7);</code> to scale the UIView , But it only can scale the UIView according to the center point
  <a href="https://i.stack.imgur.com/D1XX6.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/D1XX6.jpg" alt="enter image description here"></a></p>
  
  <p>Edit</p>
  
  <p>I try to use set anchorPoint with (0,0) but the view position be wrong</p>
  
  <p><a href="https://i.stack.imgur.com/H2xwR.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/H2xwR.jpg" alt="enter image description here"></a></p>