Does epect amp actual work with interfaces I want to define a Interface like so ```expect interface Image expect interface ImageLoader fun loadFullImage photo Photo Image fun loadThumbnailImage photo Photo Image ``` And for Android it should load a ImageBitmap ```actual interface Image actual interface ImageLoader actual fun loadFullImage photo Photo ImageBitmap actual fun loadThumbnailImage photo Photo ImageBitmap ``` And for iOS Image should be UIImage of course Is that possible

expect interface Image

expect interface ImageLoader {

    fun loadFullImage(photo: Photo): Image

    fun loadThumbnailImage(photo: Photo): Image

}

And for Android it should load a "ImageBitmap"

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actual interface Image // ???

actual interface ImageLoader {

    actual fun loadFullImage(photo: Photo): ImageBitmap

    actual fun loadThumbnailImage(photo: Photo): ImageBitmap

}

And for iOS "Image" should be "UIImage" of course. Is that possible?

✅ 1

Osman Saral

07/02/2021, 2:14 PM

I'm not sure but you can use something like this.

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expect class Image

//for Android
actual typealias Image = Bitmap

//for iOS
actual typealias Image = UIImage

after that, you can use common Interface functions to return that typealias

Stefan Oltmann

07/02/2021, 2:15 PM

I will try that. Thank you! 🙂

Ok, "actual typealias" is indeed the mechanic I'm looking for. So thank you for pointing me to that. If I try to define "actual typealias MyImage = NSImage" for my macOS target it gives an error. "actual typealias MyImage = UIImage" seems to be fine. Conflicting overloads: public final actual fun <init>(data: NSData): MyImage /* = NSImage / defined in com.sampleapp.shared.MyImage, public final actual fun <init>(contentsOfFile: String): MyImage / = NSImage / defined in com.sampleapp.shared.MyImage, public final actual fun <init>(contentsOfURL: NSURL): MyImage / = NSImage / defined in com.sampleapp.shared.MyImage, public final actual fun <init>(byReferencingFile: String): MyImage / = NSImage / defined in com.sampleapp.shared.MyImage, public final actual fun <init>(byReferencingURL: NSURL): MyImage / = NSImage / defined in com.sampleapp.shared.MyImage, public final actual fun <init>(dataIgnoringOrientation: NSData): MyImage / = NSImage */ defined in com.sampleapp.shared.MyImage

Should I file a ticket or do I just use this wrong?

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