本地通知在错误的时间发送

Posted 2023-02-24

【中文标题】本地通知在错误的时间发送

【英文标题】：local notification are sent at wrong time

【发布时间】：2015-05-12 08:24:27

【问题描述】：

我想在 ios 的特定时间每天发送 2 条本地通知，

但是通知是在错误的时间发送的，而且它每天发送多次而不是一次，

这是我的代码 sn-p，

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions 

 // are you running on iOS8?
    if ([application respondsToSelector:@selector(registerUserNotificationSettings:)])
    
        UIUserNotificationSettings *settings = [UIUserNotificationSettings settingsForTypes:(UIUserNotificationTypeBadge|UIUserNotificationTypeAlert|UIUserNotificationTypeSound) categories:nil];
        [application registerUserNotificationSettings:settings];
    
    else // iOS 7 or earlier
    
        UIRemoteNotificationType myTypes = UIRemoteNotificationTypeBadge | UIRemoteNotificationTypeAlert | UIRemoteNotificationTypeSound;
        [application registerForRemoteNotificationTypes:myTypes];
    
    application.applicationIconBadgeNumber = 0;



      //This if will be called only once....
     if ([prefs stringForKey:@"Notification"] == nil) 
     


 //... 1st notification ...

    NSDate *now = [NSDate date];
    NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
    NSDateComponents *components = [calendar components:NSYearCalendarUnit|NSMonthCalendarUnit|NSDayCalendarUnit fromDate:now];
    [components setHour:11];
    [components setMinute:24];

    // Gives us today's date but at 11am
    NSDate *next11am = [calendar dateFromComponents:components];
    if ([next11am timeIntervalSinceNow] < 0) 
        // If today's 9am already occurred, add 24hours to get to tomorrow's
        next11am = [next11am dateByAddingTimeInterval:60*60*24];
    

    UILocalNotification *notification = [[UILocalNotification alloc] init];
    notification.fireDate = next11am;
    notification.alertBody = @"Notification 1.";
    // Set a repeat interval to daily
    notification.repeatInterval = NSDayCalendarUnit;
    [[UIApplication sharedApplication] scheduleLocalNotification:notification];




//... 2nd Notification ...

    NSDate *now1 = [NSDate date];
    NSCalendar *calendar1 = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
    NSDateComponents *components1 = [calendar1 components:NSYearCalendarUnit|NSMonthCalendarUnit|NSDayCalendarUnit fromDate:now1];
    [components1 setHour:18];
    [components1 setMinute:30];

    // Gives us today's date but at 9am
    NSDate *next6pm = [calendar dateFromComponents:components];
    if ([next6pm timeIntervalSinceNow] < 0) 
        // If today's 6pm already occurred, add 24hours to get to tomorrow's
        next6pm = [next6pm dateByAddingTimeInterval:60*60*24];
    

    UILocalNotification *notification1 = [[UILocalNotification alloc] init];
    notification1.fireDate = next6pm;
    notification1.alertBody = @"Notification 2.";


    // Set a repeat interval to daily
    notification1.repeatInterval = NSDayCalendarUnit;
    [[UIApplication sharedApplication] scheduleLocalNotification:notification1];



  

我在哪里做错了？请帮忙

提前致谢！

【参考方案1】：

您检查了[prefs stringForKey:@"Notification"]，但您尚未定义prefs，因此它可能为nil，并且您似乎从未设置Notification 的值，因此它也可能丢失。任何这些都意味着您在不希望添加时添加。

您正在调用scheduleLocalNotification:，但您在任何地方都没有调用cancelLocalNotification: 或cancelAllLocalNotifications，因此，根据用户使用应用程序的方式或您进行测试的方式，您可以轻松地在以下位置添加多个通知同时。使用scheduledLocalNotifications 查看当前安排的内容。

您可能还应该使用 currentCalendar 作为日历，因为您需要尊重用户设置。

【讨论】：

在我看来日期逻辑也是错误的。我是否正确地阅读它正在创建一个日期，给定一个时间，创建一个没有时间的新日期，但 OP 期望这两个日期具有相同的时间？

@SimonMcLoughlin 看起来确实在计算和设置的 11 / 6 / 9 倍之间存在一些混淆。更详细地看，创建了 2 次但未实际使用，而是将两个通知都设置为 next9am 未定义...

查看我的新编辑@Wain：我在代码中定义了prefs，我没有在此处添加不必要的代码，如果条件我在那里写了这个//This if will be called only once....，当用户转身时有一个开关我已经写了//Notification turned Off [[UIApplication sharedApplication] cancelAllLocalNotifications]; [UIApplication sharedApplication].applicationIconBadgeNumber = 0;

好的，它现在做什么？另外，请注意您不应该使用dateByAddingTimeInterval，您应该在组件中添加一天并生成一个新日期...

仍然存在同样的问题，当我记录我的预定通知时，它显示了许多通知。喜欢<UIConcreteLocalNotification: 0x7f9e19c77920>fire date = Thursday, May 7, 2015 at 12:35:47 PM India Standard Time, time zone = Asia/Kolkata (GMT+5:30) offset 19800, repeat interval = NSCalendarUnitDay, repeat count = UILocalNotificationInfiniteRepeatCount, next fire date = Wednesday, May 13, 2015 at 12:35:47 PM India Standard Time, user info = (null)