如何在 Kotlin Jetpack Compose 中使用 rememberLauncherForActivityResult 读取文件？

Question

所以我有这个尝试从存储中读取数据的可组合项，

@Composable
private fun Screen() {
    val launcher = rememberLauncherForActivityResult(contract = ActivityResultContracts.StartActivityForResult()) { result ->
        val uri = result.data?.data.toString()
        if(uri !== null) {
            val file = File(uri)
            val bytes = file.readBytes()
            println(bytes)
        }
    }
    Column() {
        Button(onClick = {
            val intent = Intent().setType("*/*").setAction(Intent.ACTION_OPEN_DOCUMENT)
            launcher.launch(intent)
        }) {
            Text("Open file")
        }
    }
}

但是，它给了我这个错误：content:/com.android.providers.downloads.documents/document/raw%3A%2Fstorage%2Femulated%2F0%2FDownload%2FIMG_CEFEFF486A8C-1.jpeg: open failed: ENOENT (No such file or directory)。我在这里做错了什么？请帮忙

Answer 1

想通了，

@Composable
private fun Screen() {
    val context = LocalContext.current
    
    val launcher = rememberLauncherForActivityResult(contract = ActivityResultContracts.GetContent()) { result ->
        val item = context.contentResolver.openInputStream(result)
        val bytes = item?.readBytes()
        println(bytes)
        item?.close()
    }

    return Column {
        Button(onClick = {
            launcher.launch("*/*")
        }) {
            Text("Open file")
        }
    }
}