UITextField中的生日日期和检查年龄

Question

我正试图在UITextField中添加日期格式，我有一些教程，但我认为在新版本的swift中我有一些错误。

我正试图在UITextField上显示UIDatePicker点击：

@IBAction func tfDateNaissanceEditing(sender: UITextField) {
    let datePickerView:UIDatePicker = UIDatePicker()
    datePickerView.datePickerMode = UIDatePickerMode.Date
    sender.inputView = datePickerView
    datePickerView.addTarget(self, action: Selector("datePickerValueChanged:"), forControlEvents: UIControlEvents.ValueChanged)
}
@IBAction func tfDateNaissanceChanged(sender: UITextField) {
    let dateFormatter = NSDateFormatter()
    dateFormatter.dateStyle = NSDateFormatterStyle.MediumStyle
    dateFormatter.timeStyle = NSDateFormatterStyle.NoStyle
    tfDateNaissance.text = dateFormatter.stringFromDate(sender.date)
}

但是我在sender.date上得到一个错误：UITextField没有成员日期。

我想知道，如果我能得到日期，我会如何检查用户是否超过16岁？

错误

Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.
2015-12-22 16:12:51.699 Solutis[1315:72750] -[Solutis.DemandeGratuiteViewController datePickerValueChanged:]: unrecognized selector sent to instance 0x7aa7e000
2015-12-22 16:12:51.707 Solutis[1315:72750] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[Solutis.DemandeGratuiteViewController datePickerValueChanged:]: unrecognized selector sent to instance 0x7aa7e000'
*** First throw call stack:
(
    0   CoreFoundation                      0x002e5a84 __exceptionPreprocess + 180
    1   libobjc.A.dylib                     0x02185e02 objc_exception_throw + 50
    2   CoreFoundation                      0x002eedd3 -[NSObject(NSObject) doesNotRecognizeSelector:] + 275
    3   CoreFoundation                      0x0022ccdd ___forwarding___ + 1037
    4   CoreFoundation                      0x0022c8ae _CF_forwarding_prep_0 + 14
    5   libobjc.A.dylib                     0x0219a0b5 -[NSObject performSelector:withObject:withObject:] + 84
    6   UIKit                               0x00cd016a -[UIApplication sendAction:to:from:forEvent:] + 118
    7   UIKit                               0x00cd00e9 -[UIApplication sendAction:toTarget:fromSender:forEvent:] + 64
    8   UIKit                               0x00e6e19f -[UIControl sendAction:to:forEvent:] + 79
    9   UIKit                               0x00e6e51f -[UIControl _sendActionsForEvents:withEvent:] + 408
    10  UIKit                               0x00e6e1df -[UIControl sendActionsForControlEvents:] + 48
    11  UIKit                               0x0166fab1 -[_UIDatePickerView pickerView:didSelectRow:inComponent:] + 607
    12  UIKit                               0x00caecd7 -[UIPickerView _sendSelectionChangedForComponent:notify:] + 124
    13  UIKit                               0x00caee68 -[UIPickerView _sendSelectionChangedFromTable:notify:] + 137
    14  UIKit                               0x014ba31f -[UIPickerTableView _scrollingFinished] + 218
    15  UIKit                               0x014ba3d5 -[UIPickerTableView scrollViewDidEndDecelerating:] + 33
    16  UIKit                               0x00dc55a2 -[UIScrollView(UIScrollViewInternal) _stopScrollDecelerationNotify:] + 1306
    17  UIKit                               0x00dc582c -[UIScrollView(UIScrollViewInternal) _stopScrollingNotify:pin:tramplingDragFlags:] + 523
    18  UIKit                               0x00dc587e -[UIScrollView(UIScrollViewInternal) _stopScrollingNotify:pin:] + 57
    19  UIKit                               0x00dbaf7d -[UIScrollView _smoothScrollWithUpdateTime:] + 230
    20  UIKit                               0x00dbc41b -[UIScrollView _smoothScrollDisplayLink:] + 289
    21  QuartzCore                          0x05be0cfa _ZN2CA7Display15DisplayLinkItem8dispatchEv + 62
    22  QuartzCore                          0x05be0ba3 _ZN2CA7Display11DisplayLink14dispatch_itemsEyyy + 421
    23  QuartzCore                          0x05be10b5 _ZN2CA7Display16TimerDisplayLink8callbackEP16__CFRunLoopTimerPv + 123
    24  CoreFoundation                      0x00237576 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 22
    25  CoreFoundation                      0x00236f72 __CFRunLoopDoTimer + 1250
    26  CoreFoundation                      0x001f525a __CFRunLoopRun + 2202
    27  CoreFoundation                      0x001f4706 CFRunLoopRunSpecific + 470
    28  CoreFoundation                      0x001f451b CFRunLoopRunInMode + 123
    29  GraphicsServices                    0x05656664 GSEventRunModal + 192
    30  GraphicsServices                    0x056564a1 GSEventRun + 104
    31  UIKit                               0x00cce1eb UIApplicationMain + 160
    32  Solutis                             0x000652fc main + 140
    33  libdyld.dylib                       0x02be9a21 start + 1
    34  ???                                 0x00000001 0x0 + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb) 

超过18岁：

func verifAge(){
    let start = String(tfDateNaissance.text!)
    let dateFormatter = NSDateFormatter()
    dateFormatter.dateFormat = "MM-dd-yyyy"
    let startDate:NSDate = dateFormatter.dateFromString(start)
    let cal = NSCalendar.currentCalendar()

    let components = cal.components(.Year, fromDate: startDate, toDate: NSDate(), options: [])

    print(components)
}

致命错误：在展开可选值时意外发现nil

Answer 1

首先，要从DatePicker中获取所需的日期，sender是UIDatePicker的类型，而不是方法输入中声明的UITextField。

第二，参考这个答案，你可以通过获得年龄

let ageComponents = calendar.components(.Year, fromDate: sender.date, toDate: NSDate(), options: [])

编辑

您添加了一个名为datePickerValueChanged的选择器方法，但该操作的名称为tfDateNaissanceChanged。或者我应该这样说，你不需要听TextView值更改，只需要实现DataPicker值更改的方法。