title: UICollectionview allows multipleSelection not working xcode
body: <p>How to select the <code>Collection View</code> cell images using allows multiple selection is not working. Please suggest me idea or links</p>
  
  <pre><code>- (void)viewDidLoad 
    {    
     [super viewDidLoad];
     NSLog(@"photo viewer");
     [self.collectionView setPagingEnabled:NO];
     self.collectionView.allowsSelection=YES;
     [self.collectionView registerClass:[CWPhotoGalleryCell class]
      forCellWithReuseIdentifier:CWPhotoGalleryCellIdentifier];
  
     [self.collectionView scrollToItemAtIndexPath:self.selectedIndexPath atScrollPosition:UICollectionViewScrollPositionRight animated:YES];
  
      }
      -(NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView {   
      return 1;
      }
      -(NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:
      (NSInteger)section
      {
        return [self.imageArray count];
      }
  
      -(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
  
       CWPhotoGalleryCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:CWPhotoGalleryCellIdentifier
                                                                         forIndexPath:indexPath];
  
       cell.navigationControllerContainer = self.navigationController;    
       ALAsset *photo             = [self.imageArray objectAtIndex:indexPath.row];
       ALAssetRepresentation *rep = [photo defaultRepresentation];     
      CGImageRef ref = [rep fullScreenImage];
      UIImage *img   = [[UIImage alloc] initWithCGImage:ref];      
       cell.image = img;
      NSLog(@"clicked");   
      return cell;
     }
  
      -(CGSize)collectionView:(UICollectionView *)collectionView
                    layout:(UICollectionViewLayout *)collectionViewLayout
    sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
  
      return self.view.bounds.size;
      }
  
     - (void)didReceiveMemoryWarning {
       [super didReceiveMemoryWarning];
       }
  </code></pre>