iphone - 本地通知只触发一次？

Question

当用户更改日期时，我将本地通知设置为在指定日期触发

在 UIDatePicker 上。但是，当我运行应用程序时，通知正确触发，但是当

我做了一个小改动，然后再次运行，通知没有触发。这是我的

代码，请帮忙！

NSCalendar *calendar = [NSCalendar autoupdatingCurrentCalendar];

// Get the current date
NSDate *pickerDate = [datepicker date];

// Break the date up into components
NSDateComponents *dateComponents = [calendar components:( NSYearCalendarUnit | NSMonthCalendarUnit |  NSDayCalendarUnit )
                                               fromDate:pickerDate];
NSDateComponents *timeComponents = [calendar components:( NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit )
                                               fromDate:pickerDate];
// Set up the fire time
NSDateComponents *dateComps = [[NSDateComponents alloc] init];
[dateComps setDay:[dateComponents day]];
[dateComps setMonth:[dateComponents month]];
[dateComps setYear:[dateComponents year]];
[dateComps setHour:[timeComponents hour]];
[dateComps setMinute:[timeComponents minute]];
[dateComps setSecond:[timeComponents second]];
NSDate *itemDate = [calendar dateFromComponents:dateComps];
[dateComps release];


UILocalNotification *localNotif = [[UILocalNotification alloc] init];
if (localNotif == nil)
    return;

localNotif.fireDate = itemDate;
localNotif.timeZone = [NSTimeZone defaultTimeZone];
    // Notification details
    localNotif.alertBody = @"Timer";
// Set the action button
localNotif.alertAction = @"View";