findtypefromsuperview.swift

extension UIView {
    func superview<T>(of type: T.Type) -> T? {
        return superview as? T ?? superview.flatMap { $0.superview(of: type) }
    }
}

// Example usage:
func textFieldDidBeginEditing(_ textField: UITextField) {
    // Get the cell containing the textfield.
    if let cell = textField.superview(of: TextFieldTableViewCell.self) {
        cell.toggle(isHighlighted: true)
    }
}