 		collectionView?.backgroundColor = UIColor.whiteColor()
 		collectionView?.registerClass(UICollectionViewCell.classForCoder(), forCellWithReuseIdentifier: reuseIdentifier)
 		
+		navigationItem.rightBarButtonItem = UIBarButtonItem(title: "Done", style: UIBarButtonItemStyle.Done, target: self, action: "doneAction")
+		navigationItem.rightBarButtonItem?.enabled = false
+		
 		let scale = UIScreen.mainScreen().scale;
 		let cellSize = flowLayout.itemSize
 		assetGridThumbnailSize = CGSizeMake(cellSize.width * scale, cellSize.height * scale);

			
			checkMarkView = CheckMarkView(frame: CGRectMake(cell.contentView.frame.size.width - 3 - 28, 3, 28, 28))
			checkMarkView.backgroundColor = UIColor.clearColor()
			cell.contentView.addSubview(checkMarkView)
		}
		else {

	// MARK: UICollectionViewDelegate
	
	override func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
		if selectedIndexes.contains(indexPath.row) {
			selectedIndexes.remove(indexPath.row)
			navigationItem.rightBarButtonItem?.enabled = selectedIndexes.count > 0 ? true : false
		}
		else {
			navigationItem.rightBarButtonItem?.enabled = true
			selectedIndexes.insert(indexPath.row)
		}
		collectionView.reloadItemsAtIndexPaths([indexPath])
	}
	
