title: Add triangle at bottom-middle in uiimageview like marker in swift
body: <p>I am trying to add a triangle in bottom-middle position on my uiimageview but I don't know how to do that this is my code</p>
  
  <pre><code>let img_view: UIImageView!
  img_view = UIImageView(frame: CGRect(x: 0, y: 0, width: 30, height: 30))
  let url_img = URL(string: Constants.img_url+"\(img)")!
  img_view.af_setImage(withURL: url_img)
  img_view.layer.cornerRadius = img_view.frame.size.height/2
  img_view.layer.borderWidth = 1
  img_view.layer.borderColor = UIColor.rgb(red: 229, green: 57, blue: 53, alpha: 1).cgColor
  img_view.layer.masksToBounds = true
  </code></pre>
  
  <p>I wanna do that like this image1 but I have only a circle like image2</p>
  
  <p>image 1
  <a href="https://i.stack.imgur.com/KEkCT.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/KEkCT.png" alt="enter image description here"></a> </p>
  
  <p>image 2
  <a href="https://i.stack.imgur.com/dfxKL.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/dfxKL.png" alt="enter image description here"></a></p>