UICollectionView inside an UITableViewCell

问题

I've noticed iOS it's very mean when using UICollectionView inside an UITableViewCell. What I'm trying to achieve, it's to have a Collection of Images (UICollectionView approach) inside a UITableViewCell. I'm trying to mimic Facebook post style, I think, they have an UITableView, with custom cells and so on, but here's the Problem...

I've managed to put the UICollectionView inside an UITableViewCell, and It worked correctly and perfectly, no problem, everything showing fine, it's clickable and so on. BUT, I tried to refactor my code, extracting the UICollectionViewDataSource & UICollectionViewDelegate into separate files for Reusing them and having less code on the Main View Controller, it is here, when my Nightmare begun, I don't know why if I'm using separate files iOS Cycles the configuration of the Cells. For example:

-(void)configureCell:(UICollectionViewCell*)customCell atIndexPath:(NSIndexPath*)indexPath;

The above method it's being called on two parts of the process:

-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{
 NSString *identifier = [self retrieveIdentifierForIndexPath:indexPath];
 UITableViewCell *myCell = [tableView dequeueReusableCellWithIdentifier:identifier];
 [self configureCell:myCell atIndexPath:indexPath];
 [cell setNeedsLayout];
 [cell layoutIfNeeded];
 [cell setNeedsUpdateConstraints];
 [cell updateConstraintsIfNeeded];
 CGFloat height = [cell.contentView systemLayoutSizeFittingSize:UILayoutFittingExpandedSize].height;
 return height;
}

The above method it's invoked to calculate the Row Height using AutoLayout I read this on a Post here at StackOverFlow ( don't remember the post :( )

After the height it's being calculated and so on, another method calls the "configureCell" method:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    NSString *rowName = [self retrieveIdentifierForIndexPath:indexPath];
    PostDetailTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:rowName forIndexPath:indexPath];

    //PreCondition
    if([rowName isEqualToString:@"LoadingRow"]){
        return cell;
    }

    // Configure the cell...
    [self configureCell:cell atIndexPath:indexPath withImages:YES];

    [cell setSelectionStyle:UITableViewCellSelectionStyleNone];

    return cell;
}

When the debugger starts, the method configureCell:atIndexPath: it's being called over and over and over again. this is the second time this happens. Does that mean that I can't "separate" the DataSource? Or IT IS IMPOSSIBLE to add an UICollectionView inside an UITableViewCell. Or, Am I using a bad approach? Is there a way to do this?

I'm very confused on this...

Thank you guys!

回答1:

I struggled with this for a very long time, spent hours redesigning the Layouts, etc, etc. And I finally got the Solution:

This is the Header File of my Cell

@interface MyCustomTableViewCell : UITableViewCell
 @property (strong, nonatomic) IBOutlet UILabel *someLabel;
 @property (strong, nonatomic) IBOutlet UICollectionView *collectionView;

 -(void)setImages:(NSArray*)images;
@end

And Here's the Magic beyond all of this the Implementation File (m)

@interface MyCustomTableViewCell() <UICollectionViewDataSource, UICollectionViewDelegate>
 @property (strong, nonatomic) NSArray *imageArray;
@end
@implementation MyCustomTableViewCell
-(void)setImages:(NSArray*)images{
 _imageArray = images;
 [_collectionView setDataSource:self];
 [_collectionView setDelegate:self];
 [_collectionView reloadData];
}

#pragma mark - UICollectionViewDataSource Methods
...
...
...
#pragma mark - UICollectionViewDelegate Methods
...
...
...
@end

Using the Above approach made the CollectionView show and also show it's content. I also wanted to add an action to the CollectionView, for example, showing MWPhotoBrowser when an Image it's being clicked, I added a method to the Header file of the cell:

-(void)setViewController:(UIViewController*)viewController;

Seted It on the Implementation file and called the MWPhotoBrowser on the Delegate Methods. I know it's really weird, because it forces me, to use a Cell for showing the DataSource & Delegate. When I should be able to recycle my DataSource & Delegate at other points, weird. But It worked!!

Thank you, Guys!

来源：https://stackoverflow.com/questions/25999400/uicollectionview-inside-an-uitableviewcell

标签

ios

objective-c

iphone

uitableview

uicollectionviewcell