UICollectionView reloadData issue - cell's subview issue - ios

Question

I have maked following view.
But when calling -reloadData, the view becomes...
I think it's because cells is reused.
Do you have any idea to keep view as first image even if calling reloadData?
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
CustomCell* cell = [collectionView dequeueReusableCellWithReuseIdentifier:kCellIdentifier forIndexPath:indexPath];
if (indexPath.item == 0)
{
cell.label.text = #"Hello";
}
else
{
UIImage *image = dataArray[indexPath.item];
cell.imageView.image = image;
}
return cell;
}
CustomCell.m
#property (nonatomic, strong) UIImageView* imageView;
#property (nonatomic, strong) UILabel* label;
//...
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self)
{
self.imageView = [[UIImageView alloc]initWithFrame:imgViewFrame];
[self.contentView addSubview:self.imageView];
self.label = [[UILabel alloc]initWithFrame:labelFrame];
[self.contentView addSubview:self.label];
}
return self;
}
EDIT:
I modified my code.
- setting all default values before setting them with correct data
- calling -prepareForReuse
When calling -reloadData, Although imageView.image stay nil, label.text in indexPath.item==0 becomes nil and label.text in indexPath.item==3 outputs #"Hello".

Answer 1

Yes, its because of reusability. You can avoid it by changing line of code to this:
if (indexPath.item == 0)
{
cell.label.text = #"Hello";
cell.imageView.image = nil;
}
else
{
UIImage *image = dataArray[indexPath.item];
cell.imageView.image = image;
cell.label.text = #"";
}

Answer 2

When you're retrieving the dequeued cells they are already setup. So the first time you retrieve 9 different cells and initialise them accordingly.
The second time tough the cells properties are already set so you need to restart them.
So your code should look as follows:
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
CustomCell* cell = [collectionView dequeueReusableCellWithReuseIdentifier:kCellIdentifier forIndexPath:indexPath];
if (indexPath.row == 0)
{
cell.imageView.image = nil;
cell.label.text = #"Hello";
}
else
{
UIImage *image = dataArray[indexPath.item];
cell.imageView.image = image;
cell.label.text = nil;
}
return cell;
}

Answer 3

Try setting all default values of your cell before doing any check:
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
CustomCell* cell = [collectionView dequeueReusableCellWithReuseIdentifier:kCellIdentifier forIndexPath:indexPath];
//Set all default values before setting them with correct data
cell.imageView.image = nil;
cell.label.text = #"";
if (indexPath.row == 0)
{
cell.label.text = #"Hello";
}
else
{
UIImage *image = dataArray[indexPath.item];
cell.imageView.image = image;
}
return cell;
}
EDIT:
You could add this method to your CustomCell.m
- (void)prepareForReuse
{
//Set default values here
}

Answer 4

REPORT:
I solved the issue on my own.so, I will report it.
I used the property hidden.
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
CustomCell* cell = [collectionView dequeueReusableCellWithReuseIdentifier:kCellIdentifier forIndexPath:indexPath];
if (indexPath.item == 0)
{
cell.label.text = #"Hello";
cell.imageView.hidden = YES;
}
else
{
UIImage *image = dataArray[indexPath.item];
cell.imageView.image = image;
cell.label.hidden = YES;
}
return cell;
}