File Picker¶

Installation¶

Add the following dependency to your module build.gradle.kts file:

implementation("com.mohamedrejeb.calf:calf-file-picker:0.8.0")

Usage¶

Calf File Picker allows you to pick files from the device storage.

Android	iOS

Desktop	Web

val scope = rememberCoroutineScope()
val context = LocalPlatformContext.current

val pickerLauncher = rememberFilePickerLauncher(
    type = FilePickerFileType.Image,
    selectionMode = FilePickerSelectionMode.Single,
    onResult = { files ->
        scope.launch {
            files.firstOrNull()?.let { file ->
                // Do something with the selected file
                // You can get the ByteArray of the file
                file.readByteArray(context)
            }
        }
    }
)

Button(
    onClick = {
        pickerLauncher.launch()
    },
    modifier = Modifier.padding(16.dp)
) {
    Text("Open File Picker")
}

FilePickerFileType¶

FilePickerFileType allows you to specify the type of files you want to pick:

• FilePickerFileType.Image - Allows you to pick images only
• FilePickerFileType.Video - Allows you to pick videos only
• FilePickerFileType.ImageView - Allows you to pick images and videos only
• FilePickerFileType.Audio - Allows you to pick audio files only
• FilePickerFileType.Document - Allows you to pick documents only
• FilePickerFileType.Text - Allows you to pick text files only
• FilePickerFileType.Pdf - Allows you to pick PDF files only
• FilePickerFileType.All - Allows you to pick all types of files
• FilePickerFileType.Folder - Allows you to pick folders

You can filter files by custom mime types using FilePickerFileType.Custom.

val type = FilePickerFileType.Custom(
    listOf("text/plain")
)

You can also filter files by custom extensions using FilePickerFileType.Extension.

val type = FilePickerFileType.Extension(
    listOf("txt")
)

FilePickerSelectionMode¶

FilePickerSelectionMode allows you to specify the selection mode of the file picker:

• FilePickerSelectionMode.Single - Allows you to pick a single file
• FilePickerSelectionMode.Multiple - Allows you to pick multiple files

Extensions¶

• Read the ByteArray of the file using the readByteArray extension function:

val context = LocalPlatformContext.current

LaunchedEffect(file) {
    val byteArray = file.readByteArray(context)
}

The readByteArray extension function is a suspending function, so you need to call it from a coroutine scope.

It's not recommended to use readByteArray extension function on large files, as it reads the entire file into memory. For large files, it's recommended to use the platform-specific APIs to read the file. You can read more about accessing the platform-specific APIs below.

• Check if the file exists using the exists extension function:

val context = LocalPlatformContext.current

val exists = file.exists(context)

• Get the file name using the getName extension function:

val context = LocalPlatformContext.current

val name = file.getName(context)

• Get the file path using the getPath extension function:

val context = LocalPlatformContext.current

val path = file.getPath(context)

• Check if the file is a directory using the isDirectory extension function:

val context = LocalPlatformContext.current

val isDirectory = file.isDirectory(context)

Platform-specific APIs¶

KmpFile is a wrapper around platform-specific APIs, you can access the native APIs for each platform using the following properties:

Android¶

val uri: Uri = kmpFile.uri

iOS¶

val nsUrl: NSURL = kmpFile.url

Desktop¶

val file: java.io.File = kmpFile.file

Web¶

val file: org.w3c.files.File = kmpFile.file

Coil etensions¶

In case you're using Coil in your project, Calf has a dedicated package that includes utilities to ease the integration between both libraries.

You can use it by adding the following dependency to your module build.gradle.kts file:

implementation("com.mohamedrejeb.calf:calf-file-picker-coil:0.5.1")  

Currently, this package contains a KmpFileFetcher that you can use to let Coil know how to load a KmpFile by adding it to Coil's ImageLoader:

ImageLoader.Builder(context)  
 .components { add(KmpFileFetcher.Factory()) }
 .build()  

For more info regarding how to extend the Image Pipeline in Coil, you can read here.