来自核心数据的 For 循环

Question

我有一个问题，我有 2 个数组（日期和描述），一个保存我从 datePicker select 得到的日期，另一个是带有字符串的数组，两个数组都是从 CoreData 中获取的.

-(void)generateLocalNotification {
    CoreDataStack *coreDataStack = [CoreDataStack defaultStack];
    NSFetchRequest *fetchRequest = [NSFetchRequest fetchRequestWithEntityName:@"AddEntrySettings"];
    fetchRequest.resultType = NSDictionaryResultType;
    NSArray *result = [coreDataStack.managedObjectContext executeFetchRequest:fetchRequest error:nil];
    NSMutableArray *date = [result valueForKey:@"date"];
    NSMutableArray *descriere = [result valueForKey:@"descriere"];`

    if (date != nil) {
        for (NSString *stringDate in date) {
            NSDateFormatter *format = [[NSDateFormatter alloc]init];
            [format setDateFormat:@"MM/dd/yyyy h:mm a"];
            [format setTimeZone:[NSTimeZone  timeZoneWithName:@"GMT"]];
            self.date = [format dateFromString:stringDate];
            NSLog(@"LOG:%@",date);
            localNotification.fireDate = [self.date dateByAddingTimeInterval:0];
            localNotification.timeZone = [NSTimeZone timeZoneWithName:@"GMT"];

            for (int i = 0; i < descriere.count; i++) {
                localNotification.alertBody = descriere[i];
            }
            localNotification.applicationIconBadgeNumber = 1;
            localNotification.soundName = UILocalNotificationDefaultSoundName;
            localNotification.userInfo = @{@"id" : @42};

            UIApplication *app = [UIApplication sharedApplication];
            [app scheduleLocalNotification:localNotification];
        }
    }
}

当我尝试 fireDate 时，一切正常，每次当数组中的日期与当地时间匹配时，我都会收到通知，直到我尝试添加 alertBody，当我为 alertBody 制作 for 循环时，每次都会显示只是我的 NSArray 的最后一个条目。在 CoreData 中，我同时添加了两个条目。我的错误在哪里？我怎样才能每次都收到与我在 CoreData 中插入的日期相匹配的 alertBody 通知？

Answer 1

问题是这个for循环：

       for (int i = 0; i < descriere.count; i++) {
            localNotification.alertBody = descriere[i];
        }

将对每个 stringDate 迭代到描述数组中的最后一项。你想要的是在date中找到stringDate的索引，然后在descriere.

中找到相同索引处的字符串

但还有更简单的方法。不要将 result 解压缩到两个单独的数组中，只需从 for 循环中访问不同的值：

if (result != nil) {
    for (NSDictionary *dict in result) {
        NSString *stringDate = [dict objectForKey:@"date"];
        // if necessary, test whether stringDate is nil here
        NSDateFormatter *format = [[NSDateFormatter alloc]init];
        [format setDateFormat:@"MM/dd/yyyy h:mm a"];
        [format setTimeZone:[NSTimeZone  timeZoneWithName:@"GMT"]];
        self.date = [format dateFromString:stringDate];
        NSLog(@"LOG:%@",date);
        localNotification.fireDate = [self.date dateByAddingTimeInterval:0];
        localNotification.timeZone = [NSTimeZone timeZoneWithName:@"GMT"];

        localNotification.alertBody = [dict objectForKey:@"descriere"];          
        localNotification.applicationIconBadgeNumber = 1;
        localNotification.soundName = UILocalNotificationDefaultSoundName;
        localNotification.userInfo = @{@"id" : @42};

        UIApplication *app = [UIApplication sharedApplication];
        [app scheduleLocalNotification:localNotification];
    }
}

来自核心数据的 For 循环

For Loop from Core Data

for-loop

core-data

nsfetchrequest

uilocalnotification