Question

我希望在应用程序的前台或后台显示自定义提醒或弹出消息。我试过this link ，但似乎没有用。

启动应用时没有任何反应。它会说本地通知成功，但我没有看到任何弹出自定义消息框。请帮忙。

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

    //===Every 20 secs I will call setSchedule method
    NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:20 target:self selector:@selector(setSchedule) userInfo:nil repeats:YES];
    return YES;
}

-(void)setSchedule{

    NSDate *now = [NSDate date];

    NSLog(@"NSDate:%@",now);

    NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];

    [calendar setTimeZone:[NSTimeZone localTimeZone]];

    NSDateComponents *components = [calendar components:NSYearCalendarUnit|NSMonthCalendarUnit|NSDayCalendarUnit|NSHourCalendarUnit|NSMinuteCalendarUnit|NSSecondCalendarUnit|NSTimeZoneCalendarUnit fromDate:now];

    UNMutableNotificationContent *objNotificationContent = [[UNMutableNotificationContent alloc] init];

    objNotificationContent.title = [NSString localizedUserNotificationStringForKey:@"Notification!" arguments:nil];
    objNotificationContent.body = [NSString localizedUserNotificationStringForKey:@"This is local notification message!"                                                                   arguments:nil]; 
    objNotificationContent.sound = [UNNotificationSound defaultSound];

    /// 4. update application icon badge number
    objNotificationContent.badge = @([[UIApplication sharedApplication] applicationIconBadgeNumber] + 1);

    UNCalendarNotificationTrigger *trigger = [UNCalendarNotificationTrigger triggerWithDateMatchingComponents:components repeats:NO];

    UNNotificationRequest *request = [UNNotificationRequest requestWithIdentifier:@"ten"                                                                        content:objNotificationContent trigger:trigger];

    /// 3. schedule localNotification
    UNUserNotificationCenter *center = [UNUserNotificationCenter currentNotificationCenter];
    center.delegate = self;
    [center addNotificationRequest:request withCompletionHandler:^(NSError * _Nullable error) {
        if (!error) {
            NSLog(@"Local Notification succeeded");
        }
        else {
            NSLog(@"Local Notification failed");
        }
    }];

}

Answer 1

首先，UNUserNotification不会在前景中闪现。

如果你想每隔20秒或任何时间间隔发出通知，那么第二件事就是不要使用UNCalendarNotificationTrigger。

检查以下触发方法并在代码中设置。

let trigger2 = UNTimeIntervalNotificationTrigger(timeInterval: YourInterval, repeats: true)

Objective-C：设置计时器以使用UNUserNotificationCenter显示提醒

1 个答案: