title: iOS layer.borderWidth
body: <pre><code>UIView *view = [[UIView alloc]initWithFrame:CGRectMake(100,100,100,100)];
  view.backgroundColor = [UIColor redColor];
  view.layer.borderWidth = 1.0;
  view.layer.borderColor = [UIColor blueColor].CGColor;
  UIImageView *image = [[UIImageView alloc]initWithFrame:CGRectMake(-8, -10, 20, 20)];
  image.image = [UIImage imageNamed:@"sample"];
  [view addSubview:image];
  </code></pre>
  
  <p>image is on the view, but the border line is transparent・・・
  Please give me how to solve this problem.</p>