如何设置每次在UIDatepicker中显示为默认值的最短时间

在Datepicker中，我设置了最小和最大时间，其中uidatepicker可以滚动，例如我将3:00 PM设置为最小时间，晚上8:00设置为最大时间，当我运行应用程序时，我希望datepicker显示最小时间而不是当前时间该设备。 我的项目中没有硬编码的UIDatepicker在xib文件中使用过。 我已经设置了最短时间但是当我从control.tag == 1切换到2时最小时间更改以及当我第一次打开应用程序时，datepicker不会从最短时间开始。

更新：

-(IBAction)notificationButtonChanged:(UIButton *)control { if (control.tag == 1) { self.selectedButton = control.tag; [userTimePicker reloadInputViews]; [components setHour:7];; [components setMinute:00]; NSDate *date1 = [gregorian dateFromComponents:components]; [components setHour:11]; [components setMinute:00]; NSDate *date2 = [gregorian dateFromComponents:components]; [userTimePicker setDatePickerMode:UIDatePickerModeTime]; [userTimePicker setMinimumDate:date1]; [userTimePicker setMaximumDate:date2]; } if (control.tag == 2) { self.selectedButton = control.tag; [userTimePicker reloadInputViews]; [components setHour:12]; [components setMinute:00]; NSDate *date1 = [gregorian dateFromComponents:components]; [components setHour:17]; [components setMinute:00]; NSDate *date2 = [gregorian dateFromComponents:components]; [userTimePicker setDatePickerMode:UIDatePickerModeTime]; [userTimePicker setMinimumDate:date1]; [userTimePicker setMaximumDate:date2]; } } 

Answer 1

编辑：

 int startHour = 7; int endHour = 11; NSDate *date1 = [NSDate date]; NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier: NSGregorianCalendar]; NSDateComponents *components = [gregorian components: NSUIntegerMax fromDate: date1]; [components setHour: startHour]; [components setMinute: 0]; [components setSecond: 0]; NSDate *startDate = [gregorian dateFromComponents: components]; [components setHour: endHour]; [components setMinute: 0]; [components setSecond: 0]; NSDate *endDate = [gregorian dateFromComponents: components]; [userTimePicker setDatePickerMode:UIDatePickerModeTime]; [userTimePicker setMinimumDate:startDate]; [userTimePicker setMaximumDate:endDate]; [userTimePicker setDate:startDate animated:YES]; [userTimePicker reloadInputViews]; 

Answer 2

对于Swift版本：

 let startHour: Int = 6 let endHour: Int = 23 let date1: NSDate = NSDate() let gregorian: NSCalendar = NSCalendar(calendarIdentifier: NSCalendarIdentifierGregorian)! let components: NSDateComponents = gregorian.components(([.Day, .Month, .Year]), fromDate: date1) components.hour = startHour components.minute = 0 components.second = 0 let startDate: NSDate = gregorian.dateFromComponents(components)! components.hour = endHour components.minute = 0 components.second = 0 let endDate: NSDate = gregorian.dateFromComponents(components)! datePicker.datePickerMode = .Time datePicker.minimumDate = startDate datePicker.maximumDate = endDate datePicker.setDate(startDate, animated: true) datePicker.reloadInputViews() 

Answer 3

UIDatePicker类有一个setDate:animated:方法，您可以使用该方法将日期设置为日期选择器实例上所需的日期/时间。

更多信息： http ： //developer.apple.com/library/ios/documentation/uikit/reference/UIDatePicker_Class/Reference/UIDatePicker.html#//apple_ref/doc/uid/TP40006806-CH3-SW1

Answer 4

针对Swift 3进行了更新：

  let startHour: Int = 6 let endHour: Int = 23 let date1: NSDate = NSDate() let gregorian: NSCalendar = NSCalendar(calendarIdentifier: NSCalendar.Identifier.gregorian)! let components: NSDateComponents = gregorian.components(([.day, .month, .year]), from: date1 as Date) as NSDateComponents components.hour = startHour components.minute = 0 components.second = 0 let startDate: NSDate = gregorian.date(from: components as DateComponents)! as NSDate components.hour = endHour components.minute = 0 components.second = 0 let endDate: NSDate = gregorian.date(from: components as DateComponents)! as NSDate timePicker.datePickerMode = .time timePicker.minimumDate = startDate as Date timePicker.maximumDate = endDate as Date timePicker.setDate(startDate as Date, animated: true) timePicker.reloadInputViews() timePicker.frame = CGRect(x: 0.0, y: (self.view.frame.height/2 + 60), width: self.view.frame.width, height: 150.0) timePicker.backgroundColor = UIColor.white // timePicker.reloadInputViews() self.view.addSubview(timePicker) timePicker.addTarget(self, action: #selector(RoundTripViewController.startTimeDiveChanged), for: UIControlEvents.valueChanged) 

Answer 5

 datePickerObj = [[UIDatePicker alloc] initWithFrame:CGRectMake(10, 100, 300, 160)]; datePickerObj.datePickerMode = UIDatePickerModeTime; datePickerObj.backgroundColor = [UIColor clearColor]; [datePickerObj addTarget:self action:@selector(onDatePickerValueChanged:) forControlEvents:UIControlEventValueChanged]; 

将String传递给方法和格式到日期……

 -(void)Set_MinimumDate_ToDatePicker:(NSString*)Time // "start_time" = "3:00PM"; { NSDateFormatter *dformat = [[NSDateFormatter alloc]init]; [dformat setDateFormat:@"hh:mma"]; [datePickerObj setMinimumDate:[dformat dateFromString:Time]]; [datePickerObj setDate:[dformat dateFromString:Time] animated:YES]; [datePickerObj reloadInputViews]; } 

在更改选择器时，它会将时间转换为UTC + 00:00，但它会显示您的时区的时间，例如。 印度，它将UTC + 05：30添加到时间。 如果任何TimeZone问题将TimeZone设置为NSDateFormatter 。

 -(void)onDatePickerValueChanged:(UIDatePicker *)datePicker { NSDateFormatter *dformat = [[NSDateFormatter alloc]init]; [dformat setDateFormat:@"hh:mm a"]; NSLog(@"%@",datePicker.date); // 2000-01-01 11:30:00 +0000 [newStartBtn setTitle:[dformat stringFromDate:datePicker.date] forState:UIControlStateNormal]; //"05:00 PM"; }