スウィフト--- UIViewのaddSubView（UItextViewが）、何も何も表示されません

Question

class ViewController: UIViewController { 

override func viewDidLoad() { 
    super.viewDidLoad() 
    // Do any additional setup after loading the view, typically from a nib. 
    //let attstring = NSMutableAttributedString 
    let testTextView = UITextView.init(frame: CGRect.init(x: 0, y: 0, width: 100, height: 100)) 

    let attstring = NSMutableAttributedString.init(string: "You can check flights from the past 4 days, or plan 3 days ahead.\n\nTo find out when and where we fly for the rest of the year, please view our Timetable.", attributes: [NSFontAttributeName:UIFont.boldSystemFont(ofSize: 12),NSForegroundColorAttributeName:UIColor.red]) 

    attstring.setAttributes([NSForegroundColorAttributeName:UIColor.blue], range: NSRange.init(location: attstring.length-10, length: 9)) 

    print("test test!") 
    self.view.addSubview(testTextView) 
} 

を表示することができません、問題は何ですか！？迅速な3では

Answer 1

あなたはこれを書く必要があります。

let testTextView = UITextView.init(frame: CGRect.init(x: 0, y: 0, width: 100, height: 100)) 
    let attstring = NSMutableAttributedString.init(string: "You can check flights from the past 4 days, or plan 3 days ahead.\n\nTo find out when and where we fly for the rest of the year, please view our Timetable.", attributes: [NSFontAttributeName:UIFont.boldSystemFont(ofSize: 12),NSForegroundColorAttributeName:UIColor.red]) 
    testTextView.attributedText = attstring 
    attstring.setAttributes([NSForegroundColorAttributeName:UIColor.blue], range: NSRange.init(location: attstring.length-10, length: 9)) 
    self.view.addSubview(testTextView)