title: how to change UIAlertController cornerRadius
body: <p>I have created an UIAlertController like this:</p>
  
  <pre><code>    UIAlertController deleteView = [UIAlertController alertControllerWithTitle:nil message:nil preferredStyle:UIAlertControllerStyleAlert];
      deleteView.view.layer.cornerRadius = 100;
      UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:@"delete" style:UIAlertActionStyleDefault handler:nil];
      [cancelAction setValue:[NSNumber numberWithInteger:NSTextAlignmentLeft] forKey:@"titleTextAlignment"];
      [cancelAction setValue:[UIColor blackColor] forKey:@"titleTextColor"];
  </code></pre>
  
  <p>I want to change the cornerRadius of action label.</p>
  
  <p><a href="https://i.stack.imgur.com/ayC56.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ayC56.png" alt="enter image description here"></a></p>
  
  <p>I try to get the label like this:</p>
  
  <pre><code>  UIView *v1 = deleteView.view.subviews[0];
              UIView *v2 = v1.subviews[0];
              UIView *v3 = v2.subviews[0];
      UIView *v4 = v3.subviews[1].subviews[0].subviews[0];
              NSArray *arr = v5.subviews;
      NSArray *arr = v4.subviews;
      NSLog(@"v4:%@,arr:%@",v4,arr);
  </code></pre>
  
  <p>I'm getting an empty array</p>
  
  <p><a href="https://i.stack.imgur.com/jjtSC.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/jjtSC.png" alt="enter image description here"></a></p>