How to Select single cell in CollectionView and deselecting all other cell - ios

Question

**
I have horizontal CollectionView in which selected cell have orange
gradient color and all other deselected cells gray color i m
using only didselect delegate method but i am getting problem of
multiple cells selected and i have problem with same concept in table
view while scrolling and i have searched a lot but i have not get
proper answer of cell reusability
**
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
DateTimeCell * cell = [self.collectionView dequeueReusableCellWithReuseIdentifier:#"DateTimeCellID" forIndexPath:indexPath];
if (self.selectedIndexPath != nil && indexPath == self.selectedIndexPath)
{
CAGradientLayer *gradient = [CAGradientLayer layer];
gradient.frame = cell.mainView.bounds;
gradient.startPoint = CGPointZero;
gradient.endPoint = CGPointMake(1, 1);
gradient.colors = [NSArray arrayWithObjects:(id)[[UIColor colorWithRed:238.0/255.0 green:42.0/255.0 blue:123/255.0 alpha:1.0] CGColor],(id)[[UIColor colorWithRed:241.0/255.0 green:90.0/255.0 blue:41.0/255.0 alpha:1.0] CGColor], nil];
[gradient setMasksToBounds:NO];
cell.mainView.backgroundColor = [UIColor clearColor];
[cell.mainView.layer insertSublayer:gradient atIndex:0];
[indexPaths addObject:self.selectedIndexPath];
}
else
{
[cell.mainView setBackgroundColor:[self colorWithHexString:#"383F4A"]];
}
return cell;
}
-(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
indexPaths = [NSMutableArray arrayWithObjects:indexPath, nil];
if (self.selectedIndexPath)
{
// if we had a previously selected cell
if ([indexPath compare:self.selectedIndexPath] == NSOrderedSame)
{
// if it's the same as the one we just tapped on, then we're unselecting it
NSLog(#"Selected");
}
else
{
// if it's different, then add that old one to our list of cells to reload, and
// save the currently selected indexPath
[indexPaths addObject:self.selectedIndexPath];
self.selectedIndexPath = indexPath;
}
}
else
{
// else, we didn't have previously selected cell, so we only need to save this indexPath for future reference
self.selectedIndexPath = indexPath;
}
dispatch_async(dispatch_get_main_queue(), ^{
[collectionView reloadItemsAtIndexPaths:indexPaths];
});
}

Answer 1

take a global selectedIndexPath globaly like below
NSIndexPath *selectedIndexPath = [[NSIndexPath alloc] indexPathForRow:0 inSection:0];
wrilte below code in delegate methods
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
DateTimeCell * cell = [self.collectionView dequeueReusableCellWithReuseIdentifier:#"DateTimeCellID" forIndexPath:indexPath];
if self.selectedIndexPath == indexPath
{
// do what you want to do with your selected cell
}
else
{
// do what you want to do with your deselected cell
}
return cell;
}
-(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
self.selectedIndexPath = indexPath
[self.collectionView reloadData];
}