AssetCatalogAwarePre13 is a Swift Package Manager package for iOS/tvOS ( from 11.0 up to but not including 13.0) and watchOS (from 4.0 up to but not including 6.0), defining protocols and functions to access Strings, Images, and Colors, all in a type-safe manner. If you need to support iOS/tvOS (13.0 and above) or watchOS (6.0 and above), you might want to look at AssetCatalogAware, instead.
An actual practical use of AssetCatalogAwarePre13 is my AssetsPre13 framework, which also provides an example project for UIKit.
To get a sense of how AssetCatalogAwarePre13 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
}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.
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 AssetCatalogAwarePre13 will automatically pass the correct bundle to any function that requires one. Take a look at the AssetsPre13 framework to see this in action.
AssetCatalogAwarePre13 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.
AssetCatalogAwarePre13 is available under the MIT license. See the LICENSE file for more info.