UICollectionView cell dequeue issue with custom selection view - ios

Question

I have a very frustrating problem with UICollectionView and its dequeuing mechanism.
In a nutshell, I have a custom UIView with a label inside. I set this up as the selection background view in my custom cell as follows:
//My Custom Cell Class
- (instancetype)initWithCoder:(NSCoder *)aDecoder{
self = [super initWithCoder:aDecoder];
if(self){
_selectionView = (MyCustomView *)[[[NSBundle mainBundle] loadNibNamed:#"MyNibName" owner:self options:nil] objectAtIndex:0];
self.selectedBackgroundView = _selectionView;
[self bringSubviewToFront:_selectionView];
}
return self;
}
Note that all the layout work, etc for both the cell and selectedBackgroundView is done in the nibs.
Whenever the cell is selected, I'd like to set custom text in the label for selectionView so in my custom cell I also have the following method:
//In my Custom cell class
- (void) setSelectedViewLabelText:(NSString *)paramText{
if(!self.isSelected){
return;
}
self.selectionView.label.text = paramText;
}
To set the text I have in my UICollectionViewController:
- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
MyCellClass *selectedCell = (MyCellClass *)[self.collectionView cellForItemAtIndexPath:indexPath];
[selectedCell setSelectedViewLabelText:someString];
}
The problem is that whenever the UICollectionView recycles the cell, it inits them again and obviously the setSelectedViewLabelText method isn't called.
I have an annoying feeling that I may have to track the selected indexPaths and enumerate through them to see if a cell is selected and call the method, but I have potentially large data sets and can foresee how this will become a performance problem.... any ideas?
Thanks in advance!

Answer 1

Keep track of your selected cell, like:
- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
MyCellClass *selectedCell = (MyCellClass *)[self.collectionView cellForItemAtIndexPath:indexPath];
[selectedCell setSelectedViewLabelText:someString];
selectedIndexPath = indexPath;
}
In cellForItemAtIndexPath check indexPath:
-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
//.......
if([selectedIndexPath isEqual:indexPath]){
[cell setSelectedViewLabelText:someString];
}
return cell;
}
Hope this helps.. :)