set selected tag for collectionView - ios

Question

I made a UICollectionView with some cells in it and it displayed correct, now I want to set a selected tag for one or more cells, in custom cell, I can use two ways to implement it:
way 1: set selectedBackgoundView
self.selectedBackgroundView = backgroundView;
way 2: add a UIImageView as selected tag
[_coverImageView addSubview:_selectImageView];
//coverImageView is image for cell,
//selectImageView is a tag imageView for selected.
then the problem comes up:
For example I selected the first cell, When I scroll the UICollectionView, way 1 still displayed the first cell selected, but with way 2, the _selectImageView would be added to the other cell.
I know it is caused by Reuse Cell,but have no idea for deal with it.

Answer 1

Rather than adding your selected tag after you've created the cell, you should add it at the point of creation.
You don't say how you're creating your custom collection view cells, but it sounds as if you might not be using your own subclass, and are simply adding what you need to a plain UICollectionViewCell. You will find it much easier to create your own subclass, and set it up with an image view exposed that can be enabled/disabled as required. You can create custom cells either entirely in code, or in conjunction with a XIB - whichever you prefer.

Answer 2

Recently I am working on a similar project. Although It's long ago, but I hope to help someone who need it.
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
MyCollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:collectionCellID forIndexPath:indexPath];
if (cell == nil) {
cell = [[MyCollectionViewCell alloc]init];
}
//Change Selected State
if([[collectionView indexPathsForSelectedItems] indexOfObject:indexPath] != NSNotFound){
UIView *bgView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 250, 250)];
bgView.backgroundColor = kLightBlueColor;
[cell setSelectedBackgroundView:bgView];
cell.selected = YES;
}
cell.title.text = #"Hello World";
return cell;
}