Moving images to separate folder Xcode - swift

Question

I've been following Apple's own tutorials and currently trying out stuff with these files: https://developer.apple.com/tutorials/swiftui/building-lists-and-navigation
I'm checking how to get images, but for my test it will be about 100images therefore I want them in a separate folder so it does not make the resource folder messy. So instead of all the images being placed in Resource, I made a folder called "img" inside resource.
This made Xcode throw an error saying it couldn't find the images. Even after I commented out all references to all images it still throws and error saying: "/Downloads/BuildingListsAndNavigation/Complete/Landmarks/Landmarks/Resources/umbagog.jpg: No such file or directory"
Here is Apple's own code, Models/Data.swift:
final class ImageStore {
typealias _ImageDictionary = [String: CGImage]
fileprivate var images: _ImageDictionary = [:]
fileprivate static var scale = 2
static var shared = ImageStore()
func image(name: String) -> Image {
let index = _guaranteeImage(name: name)
return Image(images.values[index], scale: CGFloat(ImageStore.scale), label: Text(verbatim: name))
}
static func loadImage(name: String) -> CGImage {
guard
let url = Bundle.main.url(forResource: name, withExtension: "jpg"),
let imageSource = CGImageSourceCreateWithURL(url as NSURL, nil),
let image = CGImageSourceCreateImageAtIndex(imageSource, 0, nil)
else {
fatalError("Couldn't load image \(name).jpg from main bundle.")
}
return image
}
fileprivate func _guaranteeImage(name: String) -> _ImageDictionary.Index {
if let index = images.index(forKey: name) { return index }
images[name] = ImageStore.loadImage(name: name)
return images.index(forKey: name)!
}
}
So my question is, how do I make it store and get images in the resource/img folder instead?

Answer 1

tl;dr
Clean your project after making structural changes. Use Shift + Command + K, then build your project Command + R
Looking at the tutorial, there isn't really much you have to do to get it to read the images from a different folder. What is important is that the images are uniquely named and contained within the app's bundle.
Inside the Data.swift file, there is a function called loadImage(name:) I have copied it here so you can easily read it.
static func loadImage(name: String) -> CGImage {
guard
let url = Bundle.main.url(forResource: name, withExtension: "jpg"),
let imageSource = CGImageSourceCreateWithURL(url as NSURL, nil),
let image = CGImageSourceCreateImageAtIndex(imageSource, 0, nil)
else {
fatalError("Couldn't load image \(name).jpg from main bundle.")
}
return image
}
They key part of this is let url = Bundle.main.url(forResource: name, withExtension: "jpg"). This looks through your whole app bundle for a resource named name with the specified file extension. Once it finds it it returns the url of the resource in the bundle. That url is then used to open the image.
Downloading the tutorial project from the above link (and using the completed project); moving the images to a folder called img inside the Resources folder does not break the application. And that is all you have to do. You won't need to rename any files inside your project. Which is nice.
One thing that you will need to do, and it is probably why you are getting that error, is clean your project before rebuilding it, especially if you make structural changes. You can do that by going to to the menu Product -> Clean Build Folder, or you can also do it by pressing Shift + Command + K
Here is what is inside my Xcode project after moving the files.
Here is what is inside my directory
Why should you use the assets catalogue?
The reason for using the assets catalogue is that it allows you to have different sizes of your image, this means that big screen devices can show nice big images without loss of resolution. It also allows for app thinning, this is a process where assets that are not required by specific devices are stripped out, meaning that your app size is significantly smaller.
Asset catalogues can also have different folders within and you can have different catalogues, making it much easier to manage the assets that you have in your app.

Answer 2

In the resource folder there is a JSON file called landmarkData. The app is able to get the images from this file because the images are local to this file. When you added a new folder, all of the paths were likely messed up. In each data set of the JSON file set there is an “imageName”: image. Reformat the images like this if you really need the new folder:
“imageName”:”img/theImageName”
Hope that helps! You can always not use a new folder, but I can understand why you want it.