Multiple selections on collection view cells - ios

Question

I am trying to make an app with similar functionality to the Photos app that comes with iOS, I have the functionality that allows you to tap on a cell which expands the image to fit the screen, then tap the image to dismiss it. I now want to add the select button so that you can select multiple images that can be downloaded. I'm fairly new to this and have looked around but can't find an example that does both of these things. Any help would be great.
Update:
My current code:
func numberOfSections(in collectionView: UICollectionView) -> Int {
return 1
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return imagesURLArray.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "photoCell", for: indexPath) as! PhotoCell
cell.backgroundColor = .clear
cell.imageView.image = UIImage(contentsOfFile: imagesURLArray[indexPath.row].path)
cell.checkmarkView.isHidden = true
return cell
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout,sizeForItemAt indexPath: IndexPath) -> CGSize {
let paddingSpace = sectionInsets.left * (itemsPerRow + 1)
let availableWidth = view.frame.width - paddingSpace
let widthPerItem = availableWidth / itemsPerRow
return CGSize(width: widthPerItem, height: widthPerItem)
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout,insetForSectionAt section: Int) -> UIEdgeInsets {
return sectionInsets
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat {
return sectionInsets.left
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
addZoomedImage(indexPath.row)
addGestureToImage()
addBackGroundView()
view.addSubview(selectedImage)
}
Im not sure whereto go from here, whether its easier to add long tap gestures to select multiple images to download or to have the select button in the photos app both of which im a little clueless on where to start.

Answer 1

OK - one approach:
Design a custom button (or find one already made) that provides "CheckMark" functionality (tap to check/uncheck)
Add that button to your PhotoCell - maybe upper-left or upper-right corner
When the cell is tapped on the CheckMark button, toggle it checked/unchecked and send a message back to your controller to track its state
If the cell is tapped but not on the checkmark button, handle it as you do now with didSelectItemAt indexPath:
That's the general idea. A good next place for you is probably to take a look at some examples found by searching for uicollectionviewcell check mark

Answer 2

//works in swift 3.3 Hope it helps
//my model struct
struct Brands {
var brandId: Int = 0
var productId: Int = 0
var name: String = ""
var isChecked:Bool = false
}
var arrBrands = []//initialise arr of model
func collectionView(_ collectionView: UICollectionView,
numberOfItemsInSection section: Int) -> Int {
return arrBrands.count
}
func collectionView(_ collectionView: UICollectionView,cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let identifier: String = "brandCell"
let cell: YourCustomCell? =
collectionView.dequeueReusableCell(withReuseIdentifier: identifier,
for: indexPath) as? YourCustomCell;
let isChecked = arrBrands[indexPath.row].isChecked
cell?.brandName.font = (isChecked) ?fontForTimesRoman(withStyle:"bold", andFontsize: 14):fontForTimesRoman(withStyle: "regular",
andFontsize: 14)
cell?.brandName.text = arrBrands[indexPath.row].name
cell?.brandCheckButt.setImage((isChecked) ?UIImage(named:"filled_checkmark.png"):UIImage(named:"empty_checkmark.png"), for: .normal)
return cell!
}
func numberOfSections(in collectionView: UICollectionView) -> Int {
return 1
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
checkUncheckBrand(index: indexPath.row)
}
func collectionView(_ collectionView: UICollectionView,
didDeselectItemAt indexPath: IndexPath) {
checkUncheckBrand(index: indexPath.row)
}
func checkUncheckBrand(index:Int){
arrBrands[index].isChecked = ! (arrBrands.isChecked)
brandFilterCV.reloadData()
}