title: how to zoom in and zoom out an image on clicking button in iphone
body: <p>I have image in a imageview which is placed in a scrollview., Zoom in and out are performed  on pinches,</p>
  
  <p>now, i want to zoom in and out on clicking buttons placed for zoom in and zoom out.</p>
  
  <p>how to do it? Is there any option? if anyone knows please tell me.</p>
  
  <p>Thanks in advance.</p>