CODEWITHSUNDEEP
iosswiftuitableviewuiimage
Madian Malfi
Madian Malfi

Reputation: 610

UIImage from url takes long time to load swift

I have a UITableView with A lot of UITableViewCell, I use this code to load content and images to the UITableCell but it takes long time for the image to show for each UITableViewCell.

var loadOnce : [String] = []

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell
{

    let cell = tableView.dequeueReusableCellWithIdentifier("ProfileActivities", forIndexPath: indexPath) as! ProfileActivitiesTableViewCell


    if !loadOnce.contains("\(indexPath.row)") {

        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), {
            let LocationImage = self.postmap[indexPath.row]
            let LocationImageUrl = NSURL(string: LocationImage)
            let LocationImageData = NSData(contentsOfURL: LocationImageUrl!)

            let ProfileImage = self.postimg[indexPath.row]
            let ProfileImageUrl = NSURL(string: ProfileImage)
            let ProfileImageData = NSData(contentsOfURL: ProfileImageUrl!)

            dispatch_async(dispatch_get_main_queue(), {
                cell.locationImg.image = UIImage(data: LocationImageData!)
                cell.activitesProfileImg.image = UIImage(data: ProfileImageData!)
            });
        });
        loadOnce.append("\(indexPath.row)")

    }
    return cell
}

Putting the code in dispatch_async made scrolling smother but its still takes time to load images.

how to make it load images faster considering I have to many images something like Facebook or Instagram.

Thanks.

Upvotes: 1

Views: 5523

Answers (3)

Mrug
Mrug

Reputation: 5023

There will be issue because of Async call and ReUsability. Lets say your Image at IndexPath 1 is loading image but it is still taking time to download and meanwhile user scrolled down at some another index i.e. 15 and Internally the same cell of Index 1 is alloted to Index 15 and Image of cell 1 will be displayed in Cell 15 if you have not managed to handle previous calls for same instance of cell. Thats why its Better to use some caching library like SDWebImage(As @SeanLintern88 said) or AFNetworking's UIImageView Category

AlamoFire's UIImageView (For Swift)

Event if you wanted to do this, then better is to go with subclassing, it will help you to manage the Calls and Its termination.

In your case the Loading of Image might be because of Size of actual image that you are loading from server. CDN kind of service provide some easy to implement techniques to serve different size of images as per the request. So even If User has uploaded 1200x1200 sized image but on list screen you can fetch its 120x120 sized image, This helps is faster loading as well as it will save Physical Memories.

Upvotes: 2

ios
ios

Reputation: 975

Use one of the following libraries to asynchronously load images to you view :

1) Asyncimageview https://github.com/nicklockwood/AsyncImageView

2) SDWebImage https://github.com/rs/SDWebImage

Upvotes: 2

Sean Lintern
Sean Lintern

Reputation: 3141

It sounds like your image sizes could be large as the code looks fine, usually apps like FB/Insta would use low res renditions and then load in higher res after/when needed.

Most people use an image fetching library such as SDWebImage as this will async fetch the images and cache them so you don't have to save them on your model and consume the memory.

https://github.com/rs/SDWebImage

Upvotes: 1

Related Questions