Question

我试图在我的文本字段中添加底部边框，但是它不起作用。我知道那里也有类似的问题，但这些答案都无济于事。另外，我在下面删除了这一行代码，并尝试执行此操作，因为默认情况下没有边框，但仍然无法使用：

username.borderStyle = UITextField.BorderStyle.none

这是整个代码：

class SignUpScreen: UIViewController {

    let username = UITextField()

    override func viewDidLoad() {
        super.viewDidLoad()

        view.addSubview(username)

        // Background color
        view.backgroundColor = .white

        username.placeholder = "Name"
        username.borderStyle = UITextField.BorderStyle.none

        let bottomLine = CALayer()
        bottomLine.frame = CGRect(x: 0, y: view.frame.height - 1, width: view.frame.width, height: 1.0)
        bottomLine.backgroundColor = UIColor.black.cgColor
        username.layer.addSublayer(bottomLine)

        username.translatesAutoresizingMaskIntoConstraints = false
        username.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
        username.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
        username.widthAnchor.constraint(equalToConstant: 150).isActive = true
        username.heightAnchor.constraint(equalToConstant: 50).isActive = true

    }
}

希望有人可以帮助我！谢谢！：）

Answer 1

这是您缺少的内容：您正在使用主视图的框架创建图层的框架。您必须使用文本字段。

还应先在约束条件下正确绘制文本字段，然后在文本字段中添加图层。

在 viewDidLoad 中，您的内容视图已加载到主内存。该方法没有帧分配。因此，请使用 viewWillAppear 或 viewDidAppear 。

现在，当每次添加新的TextField和图层时将出现视图时。因此，您需要进行检查以限制该行为。例如如果文本字段已添加到您的视图中，则不要添加。

 override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)

    view.addSubview(username)

    /*
     * Create the text field
     */
    view.backgroundColor = .white
    username.placeholder = "Name"
    username.borderStyle = UITextField.BorderStyle.none
    username.translatesAutoresizingMaskIntoConstraints = false
    username.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
    username.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
    username.widthAnchor.constraint(equalToConstant: 300).isActive = true
    username.heightAnchor.constraint(equalToConstant: 50).isActive = true
}

override func viewDidAppear(_ animated: Bool) {

    super.viewDidAppear(animated)

    /*
     * Here add the shap layer
     */
    let bottomLine = CALayer()

    /*
     * Here is what you were missing.
     * You were using the main view's frame instead of your textfield
     */
    bottomLine.frame = CGRect(x: 0, y: username.bounds.height - 1, width: username.bounds.width, height: 1.0)
    bottomLine.backgroundColor = UIColor.black.cgColor
    username.layer.addSublayer(bottomLine)
}

Answer 2

bottomLine.frame = CGRect(x: 0, y: view.frame.height - 1, width: view.frame.width, height: 1.0)

您必须使用username.bounds而不是view.frame

Answer 3

除了添加图层而不是添加边界之外，还可以将其设置为UIView并将其带到 top 并设置{ {1}} textField作为bgColor：

clearColor

Answer 4

    let border = CALayer()
    let width = CGFloat(3.0)
    border.borderColor = UIColor.black.cgColor
    border.frame = CGRect(x: 0, y: textFieldOutlet.frame.size.height - width, width: textFieldOutlet.frame.size.width, height: textFieldOutlet.frame.size.height)

    border.borderWidth = width
    textFieldOutlet.layer.addSublayer(border)
    textFieldOutlet.layer.masksToBounds = true

Answer 5

尝试一下

func bottomBorderTextField(_ textField: UIView, color: UIColor) {
        // For Bottom Border
        let bottomLayer = CALayer()
        let frame = viewType.frame
        bottomLayer.frame = CGRect(x: 0, y: frame.height - 1, width: frame.width - 2, height: 0.5)
        bottomLayer.backgroundColor = color.cgColor
        viewType.layer.addSublayer(bottomLayer)
    }

在 viewDidload（）

 self.bottomBorderTextField(self.txtField, color: yourTextColor)

文本字段的底边框没有出现

5 个答案: