How to display array of images on Collection View in Swift

Question

func numberOfSections(in collectionView: UICollectionView) -> Int {
    return 1
}

func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
     print("gallery count : \(self.arrayGallerySingle.count)")
    return self.arrayGallerySingle.count
}

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "gallerycell", for: indexPath) as! GalleryViewCell
return cell
}

//API Fetching method
func galleryFetch(){

    let prs = [
        "id": dealIDGallery,
        "deal_single_page": "1" as String
    ]

    Service.StartWithoutLoading(prs as [String : AnyObject]?, onCompletion: { result in
        let jsonResponseSingle = result as? NSDictionary
        print(" jsonResponse\(String(describing: jsonResponseSingle))")

        if let resultGallery = jsonResponseSingle?.value(forKey: "result") as? NSArray{

            for keyValuesGallery in resultGallery {

                let gallerySingle = (keyValuesGallery as AnyObject).value(forKey: "gallery_images") as? NSArray

                print("Gallery Images Key: \(gallerySingle)")
                self.arrayGallerySingle = gallerySingle as! [AnyObject]

                DispatchQueue.main.async { () -> Void in
                    self.collectionView?.reloadData()

                }
            }

        }
    })
}

How will I show an array of images with key gallery_images on UICollectionViewCell?This line print("Gallery Images Key: \(gallerySingle)") prints the required array of images on console but I am unable to show on collectionView. My JSON response is http://www.jsoneditoronline.org/?id=8eccb63976d76be7d0b2d1b0e8f02306. I am using SDWebImage in my project also.I already checked datasource connection & collectionView IBoutlet as well as an image inside the cell. I am a beginner in Swift pls help and if required any further information pls ask

Answer 1

Swift 3.0 This is my updated Answer hope it will also help someone

func numberOfSections(in collectionView: UICollectionView) -> Int {
    return 1
}

func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
     print("gallery count : \(self.arrayGallerySingle.count)")
    return self.arrayGallerySingle.count

}

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "gallerycell", for: indexPath) as! GalleryViewCell
   if let imgUrl = arrayGallerySingle[indexPath.row] as? String {
        if let url = NSURL(string: imgUrl) {
            cell.galleryImage?.sd_setImage(with: url as URL, placeholderImage: UIImage(named: "place holder image"), options: .lowPriority)
        }
        else{
            let alertController = UIAlertController(title: "No Gallery Images", message: "test", preferredStyle: .alert)
            let okButton = UIAlertAction(title: "Okay", style: .default, handler: nil)
            alertController.addAction(okButton)
            alertController.present(alertController, animated: true, completion: nil)
        }
    }
return cell
}

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {
    return UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
}

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumInteritemSpacingForSectionAt section: Int) -> CGFloat {
    return 0.0
}

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat {
    return 0.0
}

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize
{
    return CGSize(width: collectionView.frame.size.width/2, height: collectionView.frame.size.height/3)

}

func galleryFetch(){

    let prs = [
        "id": dealIDGallery,
        "deal_single_page": "1" as String
    ]

    Service.StartWithoutLoading(prs as [String : AnyObject]?, onCompletion: { result in
        let jsonResponseSingle = result as? NSDictionary
        print(" jsonResponse\(String(describing: jsonResponseSingle))")

        if let resultGallery = jsonResponseSingle?.value(forKey: "result") as? NSArray{

            for keyValuesGallery in resultGallery {

                let gallerySingle = (keyValuesGallery as AnyObject).value(forKey: "gallery_images") as? NSArray

                print("Gallery Images Key: \(gallerySingle)")
                self.arrayGallerySingle = gallerySingle as! [AnyObject]

                if self.arrayGallerySingle.count > 0 {

                    DispatchQueue.main.async { () -> Void in
                        self.collectionView?.reloadData()

                    }
                } else {
                    let alertController = UIAlertController(title: "Message", message: "No images found.", preferredStyle: .alert)
                    alertController.addAction(UIAlertAction(title: "OK", style: UIAlertActionStyle.default, handler: self.doSomething))
                    self.present(alertController, animated: true, completion: nil)
                }
            }
        }
    })
}

Answer 2

Swift 3.0

you can implement this way with SDWebcache to load image in collectionView cell image.

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
            let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "gallerycell", for: indexPath) as! GalleryViewCell

            if let imgUrl = arrayGallerySingle[indexPath.row] as? String {
                if let url = URL(string: imgUrl) {
                   //Replace with your imageView outlet
                    cell.imageView.sd_setImageWithURL(url, placeholderImage: UIImage(named: "place holder image"), options: .lowPriority)
                }
            }
            return cell
        }

And If you want to display 6 cell in collectionView Then you have to set UICollectionViewLayout method to defined size of cell as below.

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize
    {
    return CGSize(width: collectionView.frame.size.width/2, height: collectionView.frame.size.height/3)

}

You can display alert when array count is not empty and why you reload Collection view inside for loop, Implement it like below.

Service.StartWithoutLoading(prs as [String : AnyObject]?, onCompletion: { result in
            let jsonResponseSingle = result as? NSDictionary
            print(" jsonResponse\(String(describing: jsonResponseSingle))")

            if let resultGallery = jsonResponseSingle?.value(forKey: "result") as? NSArray{

                for keyValuesGallery in resultGallery {

                    let gallerySingle = (keyValuesGallery as AnyObject).value(forKey: "gallery_images") as? NSArray

                    print("Gallery Images Key: \(gallerySingle)")
                    self.arrayGallerySingle = gallerySingle as! [AnyObject]
                }

                if self.arrayGallerySingle.count > 0 {

                    DispatchQueue.main.async { () -> Void in
                        self.collectionView?.reloadData()

                    }

                } else {
                    let alertController = UIAlertController(title: "Your Title", message: "their is no images", preferredStyle: .alert)
                    alertController.addAction(UIAlertAction(title: "OK", style: UIAlertActionStyle.default, handler: nil))
                    self.present(alertController, animated: tru, completion: nil)
                }

            }
        })