如何根据单元格的内容在UICollectionView中准备ForSegue？

Question

我有一个带有自定义单元格的UICollectionView，它显示字典的某些元素。

这是字典;

-(instancetype)initWithIndex:(NSUInteger)index{
self = [super init];
if (self) {

    EventsLibrary *eventsLibrary = [[EventsLibrary alloc]init];
    NSArray *library = eventsLibrary.library;

    NSDictionary *eventsDictionary = library[index];

    _eventTitle = [eventsDictionary objectForKey:kTitle];
    _eventLocation = [eventsDictionary objectForKey:kLocation];
    _eventPrice = [eventsDictionary objectForKey:kPrice];
    _eventDate = [eventsDictionary objectForKey:kDate];
    _eventTime = [eventsDictionary objectForKey:kTime];
    _eventDescription = [eventsDictionary objectForKey:kDescription];
    _eventIcon = [UIImage imageNamed:[eventsDictionary objectForKey:kIcon]];
    _eventIconLarge = [UIImage imageNamed:[eventsDictionary objectForKey:kLargeIcon]];

    _eventType = [eventsDictionary objectForKey:kType];
}
return self;
}

kVariables在标有库的数组中都有与之关联的字符串。

我已经能够在特定的视图控制器（eventTitle，eventLocation，eventPrice，eventIcon）上显示我需要的UICollectionView。我现在正在努力，因为有一个segue根据所选择的细胞作出反应。我已经成功地为UIImageView NSArray做了这个 - 但我对如何使用UICollectionView和UICollectionViewCell来解决这个问题并不熟悉。

我想执行一个segue，以便进一步显示（取决于选择了哪个单元格），字典中尚未使用的某些值（即描述）。

我是否会在performSegue方法或didSelectItemAtIndexPath中写出理想方法？

以下是一些额外的代码和屏幕截图，以获取更多信息;

具有segue标识符的两个视图控制器的故事板

初始viewcontroller的代码，其中包含关于如何填充数组以及UICollectionView标签/图像关联的UICollectionView

- (void)viewDidLoad {
[super viewDidLoad];

self.eventTitleArray = [[NSMutableArray alloc]initWithCapacity:8];
self.eventLocationArray = [[NSMutableArray alloc]initWithCapacity:8];
self.eventIconArray = [[NSMutableArray alloc]init];
self.eventPriceArray = [[NSMutableArray alloc]initWithCapacity:8];
self.eventTypeArray = [[NSMutableArray alloc]initWithCapacity:8];
self.eventDateArray = [[NSMutableArray alloc]initWithCapacity:10];

for (NSUInteger index = 0; (index < 8) ; index++){

    EventsList *eventList = [[EventsList alloc] initWithIndex:index];

    NSString *individualEventTitle = eventList.eventTitle;
    NSString *individualEventLocation = eventList.eventLocation;
    NSString *individualEventIcon = eventList.eventIcon;
    NSString *individualEventPrice = eventList.eventPrice;
    NSString *individualEventType = eventList.eventType;
    NSArray *eventDate = eventList.eventDate;


    [self.eventTitleArray addObject:individualEventTitle];
    [self.eventLocationArray addObject:individualEventLocation];
    [self.eventIconArray addObject:individualEventIcon];
    [self.eventPriceArray addObject:individualEventPrice];
    [self.eventTypeArray addObject:individualEventType];
    [self.eventDateArray addObjectsFromArray:eventDate];

    }
}

-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
EventsCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"eventsCell" forIndexPath:indexPath];

cell.eventImage.image = [self.eventIconArray objectAtIndex:indexPath.row];
cell.eventTitle.text = [self.eventTitleArray objectAtIndex:indexPath.row];
cell.eventLocation.text = [self.eventLocationArray objectAtIndex:indexPath.row];
cell.eventPrice.text = [self.eventPriceArray objectAtIndex:indexPath.row];
cell.eventType.text = [self.eventTypeArray objectAtIndex:indexPath.row];

return cell;
}

我当前能够点击模拟器中的单元格，但第二个视图控制器没有内容 - 由于segue中没有方法而推测

因此，我很欣赏一些关于如何使用UICollectionView解决这个问题的知识？

prepareForSegue

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{
EventView *collectionView = [[EventView alloc]init];
if([segue.identifier isEqual: @"showEventDetail"]){
    if([self.yourEvents indexPathForCell:sender]){
        NSIndexPath *index = [self.yourEvents indexPathForCell:sender];
        collectionView.eventTitle.text = @"Hello";
        collectionView.eventDescription.text = @"This Event";
    }
}
}

辅助viewController甚至不会将其属性collectionView.eventTitle.text更新为@"Hello"的硬字符串。虽然当我NSLog NSIndexPath *index时 - 我会根据我选择的单元格得到不同的值。所以我假设辅助VC根据所选的单元加载不同的实例？然而，我更为困惑的是，为什么在分配硬字符串值时，实际属性甚至不会改变？

Answer 1

我假设您的实际问题是是否将在performSegue方法或didSelectItemAtIndexPath 中编写理想方法。

如果是这种情况，两者都可以发挥作用。

您可以先尝试didSelectItemAtIndexPath并将模型对象（在您的情况下可能是Event）传递给详细视图控制器。这看起来像这样：

-(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath {
    // Get the Event model representing the currently selected cell
    Event *selectedEvent = self.events[indexPath.row];

    // Create a new detail view controller with the selected event and push it
    EventDetailViewController *eventDetailViewController = [[EventDetailViewController alloc] initWithEvent: selectedEvent];
    [self.navigationController pushViewController:eventDetailViewController animated:YES];
}

如果您想使用segues，您的目标是再次获得所选的indexPath。您可以使用UICollectionView的{​​{1}}方法来实现这一目标，详见this answer中所述。

请注意，如果您使用专用模型类（我前面提到的indexPathForCell），然后将一组事件作为您的数据源，它可能会大大简化您的代码。