ios - Objective-C:UILocalNotification

Question

View Controller :

- (void)viewDidLoad
{
`[super viewDidLoad];`

dateFormatter.dateFormat = @"dd/MM";
timeFormatter.dateFormat = @"HH:mm";
NSString *dateString = [dateFormatter stringFromDate:dateTime];
NSString *timeString = [timeFormatter stringFromDate:dateTime];

if ([dateString isEqual:@"23/06"]) {
    if ([timeString isEqual:@"23:30"]) {
        UILocalNotification *localNotification = [[UILocalNotification alloc] init];
        localNotification.fireDate = dateTime;
        localNotification.alertBody = [NSString stringWithFormat:@"It's 11:30 PM 23th June!"];
        localNotification.soundName = UILocalNotificationDefaultSoundName;
        localNotification.applicationIconBadgeNumber = 1;
        [[UIApplication sharedApplication] scheduleLocalNotification:localNotification];
    }
}
}

应用委托(delegate):

[[UIApplication sharedApplication] scheduledLocalNotifications];

if ([UIApplication instancesRespondToSelector:@selector(registerUserNotificationSettings:)]){

    [application registerUserNotificationSettings:[UIUserNotificationSettings settingsForTypes:UIUserNotificationTypeAlert|UIUserNotificationTypeBadge| UIUserNotificationTypeSound categories:nil]];
}

当时间等于字符串和日期时，未收到通知。请帮忙!

Answer 1

此问题的核心问题(除了使用字符串比较日期之外)是 viewDidLoad 在此应用程序中仅被调用一次。因为您只在当前日期为 11:30 时安排本地通知，所以永远不会调用它，因为您还将 fireDate 设置为相同的确切时间。

问题是，本地通知会在事件发生之前安排好。实际上，您应该将 dateTime 设置为所需的计划时间，然后设置本地通知。

例如:

- (void)viewDidLoad {

[super viewDidLoad];

NSDateComponents *dateComponents = [[NSDateComponents alloc] init];
[dateComponents setYear:2016];
[dateComponents setMonth:6];
[dateComponents setDay:23];
[dateComponents setHour:23];
[dateComponents setMinute:30];

dateTime = [[NSCalendar currentCalendar] dateFromComponents:dateComponents];

UILocalNotification *localNotification = [[UILocalNotification alloc] init];
localNotification.fireDate = dateTime;
localNotification.alertBody = [NSString stringWithFormat:@"It's 11:30 PM 23th June!"];
localNotification.soundName = UILocalNotificationDefaultSoundName;
localNotification.applicationIconBadgeNumber = 1;
[[UIApplication sharedApplication] scheduleLocalNotification:localNotification];
}

根据您上传的代码，您似乎要从 datePicker 中获取日期，因此最终，您会将 UILocalNotification 部分移动到按钮方法并使用 [ datePicker 日期] 作为 fireDate。也就是说，您可以忽略 dateComponents 部分。