Coil 3

Display a PlatformFile image with Coil 3 AsyncImage

filekit-coil lets Coil 3 load a PlatformFile directly, so you can pass a picked file to AsyncImage as its model.

Usage

build.gradle.kts

implementation("io.github.vinceglb:filekit-coil:0.17.0")

Register PlatformFile support once, in your root composable:

import io.github.vinceglb.filekit.coil.addPlatformFileSupport

@Composable
fun App() {
    setSingletonImageLoaderFactory { context ->
        ImageLoader.Builder(context)
            .components { addPlatformFileSupport() }
            .build()
    }

    MaterialTheme { /* your content */ }
}

Then use a PlatformFile as the model:

@Composable
fun Gallery(files: List<PlatformFile>, modifier: Modifier = Modifier) {
    LazyColumn(modifier) {
        items(files) { file ->
            AsyncImage(
                model = file,
                contentDescription = file.name,
                contentScale = ContentScale.Crop,
                modifier = Modifier.fillMaxWidth().height(200.dp),
            )
        }
    }
}

If you build your own ImageLoader instead of the singleton, call addPlatformFileSupport() in its components block.

Load files that need security-scoped access

Coil reads the file itself, without the security-scoped access FileKit starts around its own operations. Call securelyAccessFile from onState when the file comes from:

• the file or directory picker on iOS, which return files outside your app’s sandbox;
• a bookmark restored on iOS, or on macOS (native or JVM) when the app is sandboxed.

import io.github.vinceglb.filekit.coil.securelyAccessFile

AsyncImage(
    model = file,
    contentDescription = file.name,
    onState = { state -> state.securelyAccessFile(file) },
)

It starts access when loading begins and stops it on success or error. You don’t need it for gallery and camera results (on iOS, FileKit writes them into your app’s temporary or cache folder), for files in your app directories, or on Android and the web. Elsewhere it is a no-op, so calling it from common code is safe.

Related

• Image and video utilities to compress images or get an ImageBitmap.
• Gallery picker to let users pick photos.
• Coil documentation for transformations, placeholders, and caching.