MAUI - Android - How to read asset files?

Question

I am developing a MAUI project with VS2022. My issue comes with this snipped where I try to read two files from disk and use them as parameters for another function.

CopyFileToAppDataDirectory("vocab.json");
CopyFileToAppDataDirectory("merges.json");
var tokenizer = new Tokenizer(new Bpe(GetAssetFilePath("vocab.json"), GetAssetFilePath("merges.txt")));

Both files are part of the project, I copied them in a folder called Assets inside the Android folder.

The function Bpe throws an exception indicating that the file does not exist in the location.

System.IO.FileNotFoundException: 'Could not find file '/data/user/0/com.companyname.familytunesv3/files/vocab.json'.'

Both files have the build action set to "EmbeddedResource" and "Copy Always"

the code of the auxiliary functions

public async Task CopyFileToAppDataDirectory(string filename)
{
// Open the source file
using Stream inputStream = await FileSystem.Current.OpenAppPackageFileAsync(filename);
    
// Create an output filename
string pathfile = FileSystem.Current.AppDataDirectory + "/files/";
string targetFile = Path.Combine(pathfile, filename);
    
// Copy the file to the AppDataDirectory
using FileStream outputStream = File.Create(targetFile);
await inputStream.CopyToAsync(outputStream);
}


string GetAssetFilePath(string assetFileName)
{
var assetPath = Path.Combine(FileSystem.AppDataDirectory,assetFileName);
return assetPath;
}

any idea how to make it work?

thanks a lot.

Answer 1

I solved by setting the build action to "MauiAsset" and using the function

public async Task CopyFileToAppDataDirectory(string filename)
{
    // Open the source file
    using Stream inputStream = await FileSystem.Current.OpenAppPackageFileAsync(filename);

    // Create an output filename
    string targetFile = Path.Combine(FileSystem.Current.AppDataDirectory, filename);

    // Copy the file to the AppDataDirectory
    using FileStream outputStream = File.Create(targetFile);
    await inputStream.CopyToAsync(outputStream);
}

the final code was like this

 await CopyFileToAppDataDirectory("vocab.json");
 await CopyFileToAppDataDirectory("merges.txt");
  
 var tokenizer = new Tokenizer(new Bpe(GetAssetFilePath("vocab.json"), GetAssetFilePath("merges.txt")));