AssetCatalogAware is a Swift Package Manager package for iOS/tvOS (13.0 and above) and watchOS (6.0 and above) defining protocols and functions to access Strings, SwiftUI Fonts, System Images, non-system Images, and Colors, all in a type-safe manner. If you need to support iOS/tvOS versions below 13.0 and/or watchOS versions below 6.0, you might want to look at AssetCatalogAwarePre13, instead.
An actual practical use of AssetCatalogAware is my Assets framework, which also provides example projects for both UIKit and SwiftUI.
To get a sense of how AssetCatalogAware works, here are the protocols and some of the functions it defines for accessing Colors. The other assets are accessed in a completely similar fashion:
- Protocols:
public protocol ColorIdentifier {
var colorName: String { get }
}
public protocol ColorCatalogAware {
associatedtype ColorId: ColorIdentifier
}- Functions:
public extension ColorCatalogAware {
func color(
_ id: ColorId,
in bundle: Bundle,
compatibleWith traitCollection: UITraitCollection? = nil
) -> UIColor
func color(_ id: ColorId, in bundle: Bundle) -> Color
}Thus, any type that conforms to ColorCatalogAware is able to access a color simply by referring to its color identifier, an instance of a concrete type that implements the ColorIdentifier protocol. Typically, concrete types conforming to ColorIdentifier are enumerations and concrete types conforming to ColorCatalogAware are UIKit views and/or view controllers, and SwiftUI views.
You may have noticed that these functions take a Bundle argument. This is useful when you want to have assets in test targets, for example, but it is a bit of a nuisance to have to keep passing that argument. Sure, you could create your own versions of these functions that take a pre-defined bundle as a default but, fret not, you're covered there too. If you have a type that conforms to
public protocol AssetCatalogProvider {
var catalogBundleClass: AnyClass { get }
}then a protocol extension defined in AssetCatalogAware will automatically pass the correct bundle to any function that requires one. Take a look at the Assets framework to see this in action.
AssetCatalogAware is provided only as a Swift Package Manager package, because I'm moving away from CocoaPods and Carthage, and can be easily installed directly from Xcode.
AssetCatalogAware is available under the MIT license. See the LICENSE file for more info.