How to style UITextview to like Rounded Rect text field?

Question

I am using a text view as a comment composer.

In the properties inspector I can\'t find anything like a border style property so that I can make use a rounded rect,

Answer 1

I know there are already a lot of answers to this one, but I didn't really find any of them sufficient (at least in Swift). I wanted a solution that provided the same exact border as a UITextField (not an approximated one that looks sort of like it looks right now, but one that looks exactly like it and will always look exactly like it). I needed to use a UITextField to back the UITextView for the background, but didn't want to have to create that separately every time.

The solution below is a UITextView that supplies it's own UITextField for the border. This is a trimmed down version of my full solution (which adds "placeholder" support to the UITextView in a similar way) and was posted here: https://stackoverflow.com/a/36561236/1227119

// This class implements a UITextView that has a UITextField behind it, where the 
// UITextField provides the border.
//
class TextView : UITextView, UITextViewDelegate
{
    var textField = TextField();

    required init?(coder: NSCoder)
    {
        fatalError("This class doesn't support NSCoding.")
    }

    override init(frame: CGRect, textContainer: NSTextContainer?)
    {
        super.init(frame: frame, textContainer: textContainer);

        self.delegate = self;

        // Create a background TextField with clear (invisible) text and disabled
        self.textField.borderStyle = UITextBorderStyle.RoundedRect;
        self.textField.textColor = UIColor.clearColor();
        self.textField.userInteractionEnabled = false;

        self.addSubview(textField);
        self.sendSubviewToBack(textField);
    }

    convenience init()
    {
        self.init(frame: CGRectZero, textContainer: nil)
    }

    override func layoutSubviews()
    {
        super.layoutSubviews()
        // Do not scroll the background textView
        self.textField.frame = CGRectMake(0, self.contentOffset.y, self.frame.width, self.frame.height);
    }

    // UITextViewDelegate - Note: If you replace delegate, your delegate must call this
    func scrollViewDidScroll(scrollView: UIScrollView)
    {
        // Do not scroll the background textView
        self.textField.frame = CGRectMake(0, self.contentOffset.y, self.frame.width, self.frame.height);
    }        
}