Access Asset Catalog pathForResource

Question

It appears that:

[[NSBundle mainBundle] pathForResource:@"name" ofType:@"png"];

Does not return anything for assets that are inside the Images.xcassets asset catalog. I also tried:

[[NSBundle mainBundle] pathForResource:@"name" ofType:@"png" inDirectory:@"Images"];

[[NSBundle mainBundle] pathForResource:@"name" ofType:@"png" inDirectory:@"Images.xcassets"];

But neither of those worked either.

Has anyone had success retrieving paths to assets in the catalog?

Answer 1

Same problem, but I don't think we could access it via pathForResource:, except below:

UIImage* image = [UIImage imageNamed:@"name-in-asset-catalog"]; 

It has been clearly documented:

Each set in an asset catalog has a name. You can use that name to programmatically load any individual image contained in the set. To load an image, call the UIImage:imageNamed: method, passing the name of the set that contains the image.

I found that in the package of complied app, a file named "Assets.car" came out, and I think it's the entire images sets in my project, and should have been zipped or something.

Refer to Apple's documentation:

Xcode 5 provides different functionality for asset catalogs depending on the deployment target for your project:

• For all projects, individual images can be loaded using set names.
• For projects with a deployment target of iOS 7, Xcode compiles your asset catalogs into a runtime binary file format that reduces the download time for your app.

So that's it.

I'm also looking for a way that doesn't use imageNamed:, I don't want runtime to cache my images.

Answer 2

I wanted to access some vector assets for creating UNNotificationAttachment with local resources so I came up with this helper class. It basically just gets image from assets, saves its data to disk and return file URL. I hope that helps someone.

import UIKit  class AssetExtractor {      static func createLocalUrl(forImageNamed name: String) -> URL? {          let fileManager = FileManager.default         let cacheDirectory = fileManager.urls(for: .cachesDirectory, in: .userDomainMask)[0]         let url = cacheDirectory.appendingPathComponent("\(name).png")          guard fileManager.fileExists(atPath: url.path) else {             guard                 let image = UIImage(named: name),                 let data = UIImagePNGRepresentation(image)             else { return nil }              fileManager.createFile(atPath: url.path, contents: data, attributes: nil)             return url         }          return url     }  }