ios - 如何从 superview 获取所有元素(如 : UiLabel, UITextfield)并设置标签文本颜色和文本字段占位符颜色

Question

我在设置 UITextfield 占位符颜色和 UIlabel 文本颜色时遇到问题

1. 我们可以在给定的屏幕上看到我需要的东西。

Here is the code i am using to identify the UILabel and UITextfield.

func processSubviewsNight(of view: UIView) {

        for subview in view.subviews {

            if subview is UITextField {
                if let textField : UITextField = subview as? UITextField {
                    textField.setValue(UIColor.white, forKeyPath: "_placeholderLabel.textColor")
                      textField.backgroundColor = UIColor.appBlueColor()
                }
            }

            if subview is UILabel {
                if let label : UILabel = subview as? UILabel {
                    label.textColor = UIColor.white
                }
            }

            if subview is UIButton {
                if let button : UIButton = subview as? UIButton {
                    button.backgroundColor = UIColor.red
                }
            }
                  processSubviewsNight(of: subview)
           }
    }

1. 问题是 UITextfield 占位符和 UIButton 文本进入 UILabel 循环并更改 UITextfield 占位符颜色与 UIlabel 文本颜色相同

Answer 1

您应该在 else 条件下调用 processSubviewsNight(of: subview)。否则，文本字段的 subview 将传递给此方法。

func processSubviewsNight(of view: UIView) {

        for view in self.view.subviews {
            if let lbl = view as? UILabel {
                label.textColor = UIColor.white
            } else if let textField = view as? UITextField {
                textField.setValue(UIColor.white, forKeyPath: "_placeholderLabel.textColor")
                textField.backgroundColor = UIColor.appBlueColor()
            } else if let button = view as? UIButton {
                button.backgroundColor = UIColor.red
            } else{
                processSubviewsNight(of: view)
            }
        }

    }