ios - 如何用 subview 隐藏 UITextField 文本？

Question

我需要用 subview 隐藏 UITextField 的文本属性。 这看起来很简单，但不幸的是它不起作用。 我做错了什么？

代码如下:

override func viewDidLoad() {
    super.viewDidLoad()

    let txtField = UITextField()
    txtField.frame = CGRect(x: 10, y: 50, width: 300, height: 30)
    txtField.text = "This text is hidden under UILabel"
    txtField.backgroundColor = UIColor.blueColor()
    view.addSubview(txtField)

    let label = UILabel()
    label.frame = CGRect(x: 0, y: 0, width: 300, height: 30)
    label.backgroundColor = UIColor.redColor()
    label.textColor = UIColor.whiteColor()
    label.text = "This text should appear on top"

    txtField.addSubview(label)
    txtField.bringSubviewToFront(label)
}

Answer 1

    let txtField = UITextField()
    txtField.frame = CGRect(x: 10, y: 50, width: 300, height: 30)
    txtField.text = "This text is hidden under UILabel"
    view.addSubview(txtField)

    let label = UILabel()
       let label = UILabel()
   // label.frame = CGRect(x: 0, y: 0, width: 300, height: 30)
    label.frame = txtField.frame
    label.backgroundColor = UIColor.redColor()
    label.textColor = UIColor.whiteColor()
    label.text = "This text should appear on top"


    label.backgroundColor = UIColor.redColor()
    label.textColor = UIColor.whiteColor()
    label.text = "This text should appear on top"

    view.addSubview(label) // add label on view with same position ...

或者您只需更改标签的 z 顺序，它也能正常工作。

    let txtField = UITextField()
    txtField.frame = CGRect(x: 10, y: 50, width: 300, height: 30)
    txtField.backgroundColor = UIColor.yellowColor()
    txtField.text = "This text is hidden under UILabel"
    view.addSubview(txtField)

    let label = UILabel()
    label.frame = CGRect(x: 0, y:0, width: 300, height: 30)
    label.backgroundColor = UIColor.redColor()
    label.textColor = UIColor.whiteColor()
    label.text = "This Label should appear on top"
    label.layer.zPosition=1
    txtField.addSubview(label)