ios - 根据所选日期快速从手动 datePicker 获取时间

Question

我有两个字段，称为日期和时间。我正在使用此代码创建日期选择器

var selectedDate : NSDate!
func date_picker2(textField: UITextField)
    {
        var toolbar1:UIToolbar = UIToolbar(frame: CGRectMake(0, 0, UIScreen.mainScreen().bounds.size.width, 40))
        var done:UIBarButtonItem = UIBarButtonItem(title: "Done", style: UIBarButtonItemStyle.Plain, target:self, action: Selector("cancelBtnClicked1:"))
        done.tag  = 203
        var cancel:UIBarButtonItem = UIBarButtonItem(title: "Cancel", style: UIBarButtonItemStyle.Plain, target: self, action: Selector("cancelBtnClicked1:"))

        cancel.tag = 202


   var space:UIBarButtonItem = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.FlexibleSpace, target: nil, action: nil)
    toolbar1.items = [cancel,space,done]
    toolbar1.barTintColor = UIColor(red: 23.0/255.0, green: 174.0/255.0, blue: 202.0/255.0, alpha: 1)
    toolbar1.tintColor = UIColor.whiteColor()
    txt_Dob.inputAccessoryView = toolbar1
    txt_birthTime.inputAccessoryView = toolbar1

    datePicker = UIDatePicker(frame: CGRectMake(toolbar1.frame.size.width - 65, 0, 0, 300))
    let currentCalendar = NSCalendar.currentCalendar()

    let dateComponents = NSDateComponents()
    dateComponents.year = -80
    datePicker.maximumDate = NSDate()


    if txt_Dob.isFirstResponder()
    {
        datePicker.datePickerMode = UIDatePickerMode.Date
    }
    if txt_birthTime.isFirstResponder()
    {
        datePicker.datePickerMode = UIDatePickerMode.Time
        println("selectedDate: \(selectedDate)")
        if selectedDate == NSDate(){
            datePicker.maximumDate = NSDate(timeIntervalSinceNow:0)
        }
    }

    datePicker.timeZone = NSTimeZone.localTimeZone()
    datePicker.locale = NSLocale.currentLocale()
    datePicker.calendar = NSCalendar.currentCalendar()
    datePicker.backgroundColor = UIColor.whiteColor()
    txt_Dob.inputView = datePicker
    txt_birthTime.inputView = datePicker
}

func cancelBtnClicked1(sender:UIButton!)
{
    var btnTag = sender.tag

    if btnTag == 203
    {
        if( txt_Dob.isFirstResponder())
        {
            if sender.tag == 203
            {
                var dateFormatter = NSDateFormatter()
                dateFormatter.dateFormat = "dd-MM-yyyy"
                txt_Dob.text = dateFormatter.stringFromDate(datePicker.date)

            }
        }
        else if( txt_birthTime.isFirstResponder())
        {
            if sender.tag == 203
            {
                var dateFormatter = NSDateFormatter()
                dateFormatter.dateFormat = "HH:mm"
                txt_birthTime.text = dateFormatter.stringFromDate(datePicker.date)
               }
        }
        txt_Dob.resignFirstResponder()
        txt_birthTime.resignFirstResponder()
    }
    else
    {
        self.view.endEditing(true)
    }
}

现在我希望如果我选择今天的日期选择器应该允许我花到现在为止的时间，但是如果我选择前天的日期，它应该允许我花任何时间。

我不知道该怎么做。谁能建议我该怎么做？

谢谢..

Answer 1

只需更新时间选择器的最大日期并匹配当前日期，例如:

dateComponents.hour = 23
dateComponents.minute = 59
dateComponents.second = 59

datePicker.maximumDate = currentCalendar?.dateByAddingComponents(components, toDate: NSDate(), options: NSCalendarOptions())

if txt_Dob.isFirstResponder()
{
    datePicker.datePickerMode = UIDatePickerMode.Date
}
if txt_birthTime.isFirstResponder()
{
    datePicker.datePickerMode = UIDatePickerMode.Time
    if selectedDate == NSDate(){
    datePicker.maximumDate = NSDate(timeIntervalSinceNow:0)
    }
}

当用户从 txt_Dob 日期选择器中选择日期时，您必须更新 selectedDate。

if( txt_Dob.isFirstResponder())
    {
        if sender.tag == 203
        {
            var dateFormatter = NSDateFormatter()
            dateFormatter.dateFormat = "dd-MM-yyyy"
            txt_Dob.text = dateFormatter.stringFromDate(datePicker.date)
            selectedDate = datePicker.date
            txt_birthTime.text = ""
        }
    }