在一天中的特定時間發送本地通知

Question

我想從數組中獲取隨機字符串，然后每天早上7點顯示。

這是我的AppDelegate.m中的代碼

-(void)applicationDidEnterBackground:(UIApplication *)application
{ 

    QuoteTableViewController *quoteVC;
        int randomlyGeneratedNumber;
        randomlyGeneratedNumber =arc4random()%[quoteVC.arrayOfOurQuotes count];
        NSString *stringOfTheDay = [[NSString alloc] init];
        stringOfTheDay = [quoteVC.arrayOfOurQuotes objectAtIndex:randomlyGeneratedNumber];
        NSLog(@"%@",stringOfTheDay);

        NSCalendar *calendar = [NSCalendar autoupdatingCurrentCalendar];

        NSDateComponents *componentsForReferenceDate = [calendar components:(NSCalendarUnitDay | NSCalendarUnitYear | NSCalendarUnitMonth ) fromDate:[NSDate date]];

        [componentsForReferenceDate setDay:9];
        [componentsForReferenceDate setMonth:11];
        [componentsForReferenceDate setYear:2012];

        NSDate *referenceDate = [calendar dateFromComponents:componentsForReferenceDate];
        NSDateComponents *componentsForFireDate = [calendar components:(NSCalendarUnitYear | NSCalendarUnitHour | NSCalendarUnitMinute | NSCalendarUnitSecond ) fromDate: referenceDate];

        [componentsForFireDate setHour:7];
        [componentsForFireDate setMinute:0];
        [componentsForFireDate setSecond:0];

        NSDate *fireDateOfNotification = [calendar dateFromComponents:componentsForFireDate];

        // Create the notification

        UILocalNotification *notification = [[UILocalNotification alloc] init];
        if (notification) {
            notification.fireDate = fireDateOfNotification;
            notification.timeZone = [NSTimeZone localTimeZone];
            notification.repeatInterval = 0;
            notification.alertBody = [NSString stringWithFormat:stringOfTheDay];
            notification.soundName = UILocalNotificationDefaultSoundName;
            notification.applicationIconBadgeNumber = 1;
            [[UIApplication sharedApplication] scheduleLocalNotification:notification];
        }
}

運行代碼時此行存在錯誤

randomlyGeneratedNumber =arc4random()%[quoteVC.arrayOfOurQuotes count];

我的其他View Controller中有一個數組。 我確實導入了視圖控制器。

編輯：數組內部有字符串，但是當導入到應用程序委托中時，它變為0。如何解決此問題？

Answer 1

您需要將“ arrayOfOurQuotes”實現為您的應用程序委托的屬性，而不是視圖控制器。 當視圖消失時，視圖控制器以及數組將不再存在-如果您已經進入背景，則顯然是這種情況。