xcode - 设置 DatePicker 的时间

Question

如何将 DatePicker 的时间设置为当前日期的 00:00:00？

   - (void) awakeFromNib
    {
        [datePicker setDateValue:[NSDate date]];
        NSDate *now = [NSDate date];
        int daysToAdd = 364;
        NSDate *newDate1 = [now dateByAddingTimeInterval:60*60*24*daysToAdd];
        [datePicker1 setDateValue:newDate1];
    }

Answer 1

畏缩

看起来您有两个不同的日期选择器？ datePicker和datePicker1？那是怎么回事？

此外，这不会满足您的期望：

NSDate *newDate1 = [now dateByAddingTimeInterval:60*60*24*364];

那就是创建一个新的日期，它正好是未来 31,449,600 秒。除此之外，它没有做任何事情。

您想要做的是从当前日期中提取所有日期组件并将它们归零：

NSDate *now = [NSDate date];
NSDateComponents *nowComponents = [[NSCalendar currentCalendar] components:(NSEraCalendarUnit | NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit) fromDate:now];

// technically these next lines are unnecessary, since we only pulled out the era-year-month-day, but they're included here for understanding/completeness:

[nowComponents setHour:0];
[nowComponents setMinute:0];
[nowComponents setSecond:0];

// now we can turn it back into a date:

NSDate *todayAtMidnight = [[NSCalendar currentCalendar] dateFromComponents:nowComponents];