ios - 在特定日期触发UILocalNotification

Question

我想在特定的日期触发UILocalNotification。如果我使用此代码:

NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDateComponents *components = [gregorian components:NSYearCalendarUnit | NSMonthCalendarUnit |  NSDayCalendarUnit fromDate:[NSDate date]];

[components setHour:4];
[components setMinute:0];

NSDate *fireDate = [gregorian dateFromComponents:components];

如果现在是下午3点，则可以正常工作，但是例如在下午5点时，则不能正常工作。

如何将通知生效日期设置为“下一个下午4点”？

Answer 1

NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDateComponents *components = [gregorian components:NSYearCalendarUnit | NSMonthCalendarUnit |  NSDayCalendarUnit fromDate:[NSDate date]];

[components setHour:4];
[components setMinute:0];

NSDate *fireDate = [gregorian dateFromComponents:components];
 NSLog(@"Fire date : %@",fireDate);// Today 4pm is already passed. So you wont get notification 

// You need to check if the time is already passed
if ([fireDate compare:[NSDate date]] == NSOrderedAscending)
{
    // Schedule it for next day 4pm
    components.day = components.day+1;
    fireDate = [gregorian dateFromComponents:components];
}
NSLog(@"Fire date : %@",fireDate);