如何使用UILocalnotification每天23:00调用推送通知

Question

我想使用UILocalNotification实现推送通知。 所以我写了这段代码，但它多次调用，时间不是23:00而是23：13,23：34,23：xx

-(void)application:(UIApplication *)application performFetchWithCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler
{      
    [[UIApplication sharedApplication] cancelAllLocalNotifications];
    NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
    NSDate *now = [NSDate date];
    NSDateComponents *componentsForFireDate = [calendar components:(NSYearCalendarUnit | NSWeekCalendarUnit |  NSHourCalendarUnit | NSMinuteCalendarUnit| NSSecondCalendarUnit | NSWeekdayCalendarUnit) fromDate: now];


    [componentsForFireDate setHour: 23] ; //for fixing 23PM hour
    [componentsForFireDate setMinute:0] ;
    [componentsForFireDate setSecond:0] ;
    UILocalNotification* notifyAlarm = [[UILocalNotification alloc]
                                        init];

    NSLog(@"____date is %@",[calendar dateFromComponents:componentsForFireDate]);
    notifyAlarm.fireDate = [calendar dateFromComponents:componentsForFireDate];
    notifyAlarm.timeZone = [NSTimeZone defaultTimeZone];
    notifyAlarm.repeatInterval = 0;
    notifyAlarm.alertBody = @"hello";


    [[UIApplication sharedApplication] scheduleLocalNotification:notifyAlarm];

我想修复23:00并拨打一次电话。 你有什么主意吗？

提前致谢。