RemoteImage

This Swift package provides a wrapper view around the existing SwiftUI Image view which adds support for showing and caching remote images. In addition you can specify a loading and error view.

You can display images from a specific URL or from the iCloud (through a PHAsset identifier).

💡 Installation

Add this Swift package in Xcode using its Github repository url. (File > Swift Packages > Add Package Dependency…)

🧭 How to use

Just pass a remote image url or the local identifier of a PHAsset and ViewBuilders for the error, image and loading state to the initializer. That’s it 🎉

Clear the image cache through RemoteImageService.cache.removeAllObjects().

📖 Examples

The following code truly highlights the simplicity of this view:

URL example:

let url = URL(string: "https://images.unsplash.com/photo-1524419986249-348e8fa6ad4a?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=1950&q=80")!

RemoteImage(type: .url(url), errorView: { error in
    Text(error.localizedDescription)
}, imageView: { image in
    image
    .resizable()
    .aspectRatio(contentMode: .fit)
}, loadingView: {
    Text("Loading ...")
})

PHAsset example:

RemoteImage(type: .phAsset(localIdentifier: "541D4013-D51C-463C-AD85-0A1E4EA838FD"), errorView: { error in
    Text(error.localizedDescription)
}, imageView: { image in
    image
    .resizable()
    .aspectRatio(contentMode: .fit)
}, loadingView: {
    Text("Loading ...")
})

Custom RemoteImageURLDataPublisher

Under the hood the URLSession.shared is used by default as the RemoteImageURLDataPublisher to fetch the image at the specified URL. You can specify a custom publisher through theremoteImageURLDataPublisher parameter. As an example that’s how you could add support for low data mode to the RemoteImage view.

let url = URL(string: "https://images.unsplash.com/photo-1524419986249-348e8fa6ad4a?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=1950&q=80")!

RemoteImage(type: .url(url), remoteImageURLDataPublisher: {
    let configuration = URLSessionConfiguration.default
    // Enable low data mode support
    configuration.allowsConstrainedNetworkAccess = false
    return URLSession(configuration: configuration)
}(), errorView: { error in
    Text(error.localizedDescription)
}, imageView: { image in
    image
    .resizable()
    .aspectRatio(contentMode: .fit)
}, loadingView: {
    Text("Loading ...")
})

Custom RemoteImageService

If you want complete control over the service responsible for managing the state of the view and for fetching the image you could pass an object conforming to the RemoteImageService protocol to the related initializer:

final class CustomService: RemoteImageService { ... }

let url = URL(string: "https://images.unsplash.com/photo-1524419986249-348e8fa6ad4a?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=1950&q=80")!

RemoteImage(type: .url(url), service: CustomService(), errorView: { error in
    Text(error.localizedDescription)
}, imageView: { image in
    image
    .resizable()
    .aspectRatio(contentMode: .fit)
}, loadingView: {
    Text("Loading ...")
})

In addition to that you could use the new @StateObject property wrapper introcuded in Swift by creating an instance of the default built-in RemoteImageService and using the above initializer:

@StateObject var service = DefaultRemoteImageServiceFactory.makeDefaultRemoteImageService()
// or
@StateObject var service = DefaultRemoteImageServiceFactory.makeDefaultRemoteImageService(remoteImageURLDataPublisher: yourRemoteImageURLDataPublisher)

let url = URL(string: "https://images.unsplash.com/photo-1524419986249-348e8fa6ad4a?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=1950&q=80")!

RemoteImage(type: .url(url), service: service, errorView: { error in
    Text(error.localizedDescription)
}, imageView: { image in
    image
    .resizable()
    .aspectRatio(contentMode: .fit)
}, loadingView: {
    Text("Loading ...")
})

Custom cache

The RemoteImageService uses a default cache. To use a custom one just conform to the protocol RemoteImageCache and set it on the type RemoteImageService.

RemoteImageService.cache = yourCache

Custom cache key

The default cache uses the associated value of the related RemoteImageType as the key. You can customize this by setting a cache key provider through

RemoteImageService.cacheKeyProvider = { remoteImageType -> AnyObject in
    // return a key here
}

Migration from 0.1.0 -> 1.0.0

The url parameter was refactored to a type parameter which makes it easy to fetch images at a URL or from the iCloud.

Change

# Version 0.1.0
let url = URL(string: "https://images.unsplash.com/photo-1524419986249-348e8fa6ad4a?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=1950&q=80")!

RemoteImage(url: url, errorView: { error in
    Text(error.localizedDescription)
}, imageView: { image in
    image
    .resizable()
    .aspectRatio(contentMode: .fit)
}, loadingView: {
    Text("Loading ...")
})

to

# Version 1.0.0
let url = URL(string: "https://images.unsplash.com/photo-1524419986249-348e8fa6ad4a?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=1950&q=80")!

RemoteImage(type: .url(url), errorView: { error in
    Text(error.localizedDescription)
}, imageView: { image in
    image
    .resizable()
    .aspectRatio(contentMode: .fit)
}, loadingView: {
    Text("Loading ...")
})