问题
I am implementing something with a date selection and it turns out that Apple's implementation of UIDatePicker uses infinite loop for days and months. In plain english, it is impossible to hit a ceiling of 1 nor the bottom that is 12 or 31. It just loops forever starting both sets again with 1 and so on which is from my very subjective perspective the stupidest idea on this UI component.
The UX with this picker is such that the speed of spinning is very fast so it is actually difficult to hit the right number. If it is november, and I need february, it would be much faster to just hit the top with fast vert. swipe, and then do a slight move down to Feb, which I would prefer over a few shaky moves until I find Feb in the infinite set.
Looking at the class reference, I can't seem to find anything. Nor it's superclass seems to have a suitable property.
Any appstore-safe ideas (exc. custom implementation..as a last resort)?
回答1:
I have used this code below from another stackoverflow question in the past and works well.
How to set Minimum time to appear as default in UIDatepicker everytime
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];
来源：https://stackoverflow.com/questions/29198769/how-to-disable-infinite-scrolling-in-uidatepicker