来自Firebase的缓存图片

Question

I have multiple cells that currently hold different photos from Firebase. Every time a user loads these images then scrolls, they are re-downloaded which eats up data fast. I find this concerning to any user who has a metered data plan. What could I do to solve this? Does Firebase offer any options to cache downloaded images?

This is how I am currently calling an image into a cell:

if let imageName = post["image"] as? String {
        let imageRef = FIRStorage.storage().reference().child("images/\(imageName)")
        imageRef.data(withMaxSize: 25 * 1024 * 1024, completion: { (data, error) -> Void in if error == nil {
            let image = UIImage(data: data!)
            cell.postImageView.image = image

Answer 1

Use Kingfisher to cache images. It's light and very easy to use. Just pass your url from firebase and it will automatically cache it.

let url = URL(string: "url_of_your_image")
imageView.kf.setImage(with: url)

Answer 2

Firebase already does cache the database locally, before it fetch real-time data from the server, so the problem is not as severe. But if you want to do better caching, use Glide , Glide caches images and you can specify time signatures so it re-fetches images only if they are updated.

This is super easy, but you do need to host your images in google cloud services, or aws, or anywhere even

 ImageView imageView = (ImageView) findViewById(R.id.my_image_view);
 Glide.with(this).load("url").into(imageView);

Answer 3

You might use Alamofire too. It does not handle caching automatically though, but against Kingfisher, it has the ability to handle almost all kinds of networking needs.

PS: Yes I know that -generally- I do not need any networking capabilities if I'm using Firebase.

But, for example; since Firebase Database and Firestore cannot handle full-text search, you need to use third-party solutions, so, you might be in need of full-featured networking utility sometime.