UITableView内的UICollectionView部分中的错误行

Question

I have a UITableView in the Groups (Sectioned) mode. Each section of the table contains about 5 cells. Each cell of the table consists of one UILabel and one UICollectionView . UICollectionView will contain a set of simple items with a horizontal scrolling.

So, I have something like a Grid View and it looks in Storyboard like:

In the Simulator it looks like:

The problems that I can't understand:

When I scroll any of the rows horizontally - some another row (that may be in the same or some another section) can synchronously scrolls with the first one, looks like they have some connection with each other or it's the same UICollectionView !

How can I use different UICollectionView in each UITableViewCell or break that "strange connection"?

My code (Header):

@interface ipAthleteHistoryTableViewController : UIViewController <UICollectionViewDataSource, UITableViewDataSource, UITableViewDelegate>

@property (weak, nonatomic) IBOutlet UITextField *datesRangeFromPeer;
@property (weak, nonatomic) IBOutlet UITextField *datesRangeToPeer;

@property (weak, nonatomic) IBOutlet UITableView *history;

- (IBAction)datesRangeFromPeerEditingExited:(id)sender;
- (IBAction)datesRangeFromPeerSet:(id)sender;

- (IBAction)datesRangeToPeerEditingExited:(id)sender;
- (IBAction)datesRangeToPeerSet:(id)sender;

- (IBAction)todaySpeedButtonPressed:(id)sender;
- (IBAction)weekSpeedButtonPressed:(id)sender;
- (IBAction)monthSpeedButtonPressed:(id)sender;
- (IBAction)quarterSpeedButtonPressed:(id)sender;

@end

Implementation:

- (void)viewDidLoad
{
    _dumbNumberOfItems = 24;
    _dumbNumberOfItems2 = 5;

    [super viewDidLoad];
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return _dumbNumberOfItems2;
}

- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
{
    return _dumbNumberOfItems;
}

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return 5;
}

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section
{
    return [NSString stringWithFormat:@"12.09.2014:%ld", (long)section];
}

- (UITableView *)findParentTableView:(UITableViewCell *)tableCellView
{
    return (UITableView *)[ipNavigationHelper findParentViewOfClass:[UITableView class]
                                                    ofChildView:tableCellView];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{       
    ipAthleteHistoryTableCell *cell = [tableView dequeueReusableCellWithIdentifier:athleteHistoryChart_ExcerciseTrialsCell forIndexPath:indexPath];

    [[cell excerciseTitle] setText:[NSString stringWithFormat:@"Title %li:%li; %ld", [indexPath section], (long)[indexPath row], (long)[cell excerciseTrials]]];
    [[cell excerciseTrials] reloadData];

    return cell;
}

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
    ipAthleteHistoryExcerciseTrialCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:athleteHistoryChart_TrialCell
                                                                                     forIndexPath:indexPath];
    ipAthleteHistoryTableCell *upCell = [self findParentTableCell:collectionView];

    [[cell actualTrial] setText:[ipNumeralsConverter convertToLatinArabNumber:[indexPath row]]];
    [[cell actualRepeats] setText:[NSString stringWithFormat:@"%li", [[[self findParentTableView:upCell] indexPathForCell:upCell] section]]];
    [[cell targetRepeats] setText:[NSString stringWithFormat:@"%li", [[[self findParentTableView:upCell] indexPathForCell:upCell] row]]];
    [[cell workWeight] setText:[NSString stringWithFormat:@"%li", [indexPath row]*10]];

    return cell;
}

All the initial work (like IDs registration, cells prototyping, etc.) is done using Storyboard.

Answer 1

Your problem is probably related to the fact that UITableViewCells get reused. So when you scroll and see a new cell, it really is just one of the cells that went away. To deal with your issues, you'll need to make sure the cell is properly initialized in cellForRowAtIndexPath and make sure you override any previous data you had in there.

Answer 2

Ok, finally I've decided to escape from the cells reusing functionality by creating unique Cell IDs and creating it "on-the-fly" without Storyboard prototyping. It looks fine now.

The code is standard:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    NSString *cellId = [NSString stringWithFormat:@"%@-%ld-%ld",
                                             athleteHistoryTable_ExcerciseTrialsCell,
                                             (long)[indexPath section],
                                             (long)[indexPath row]];
    ipAthleteHistoryTableCell *cell = [tableView dequeueReusableCellWithIdentifier:cellId];
    if (cell == nil)
    {
        cell = [[ipAthleteHistoryTableCell alloc] initWithStyle:UITableViewCellStyleDefault
                                            reuseIdentifier:cellId];

        [[cell excerciseTrials] registerClass:[ipAthleteHistoryExcerciseTrialCell class]
               forCellWithReuseIdentifier:athleteHistoryTable_TrialCell];

        [[cell excerciseTrials] setDataSource:self];
    }

    [[cell excerciseTitle] setText:[NSString stringWithFormat:@"Excercise Title %li:%li; %ld",
                                                         [indexPath section],
                                                         (long)[indexPath row],
                                                         (long)[cell excerciseTrials]]];

    [[cell excerciseTrials] reloadData];

    return cell;
}