如何在 android 应用程序中提示文件管理器进入已知路径？

Question

I have the following activity in my application:

public class DisplaySettingsActivity extends AppCompatActivity implements View.OnClickListener {
    
    Button saveIntoFile;
    TextView msg;

    private ActivityResultLauncher<String> requestPermissionLauncher;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_display_settings);
        
        requestPermissionLauncher = registerForActivityResult(new ActivityResultContracts.RequestPermission(), isGranted -> {
            Log.d("H300s","Permissions Callback");

            if (isGranted) {
                Log.d("H300s","Permission Accepted 2");
                saveFile();
            } else {
                permissionSaveDenied();
            }
        });

        this.saveIntoFile = (Button)findViewById(R.id.save);
        this.saveIntoFile.setOnClickListener(this);
    }

    private void saveFile(){
        Log.d("Η300s","Saving");
        String state = Environment.getExternalStorageState();
        if (!Environment.MEDIA_MOUNTED.equals(state)) {
            Log.e("H300s","Unable to detect external storage");
            saveMsgHandler(null);
            return;
        }

        this.saveIntoFile.setEnabled(false);

        DateTimeFormatter pattern = DateTimeFormatter.ofPattern("yyyMMdd");
        File file = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS);

        file = new File( file.getAbsolutePath(),"voip_h300s_"+pattern.format(LocalDate.now())+".txt");
        Log.d("H300s",file.toString());
        try {
            file.createNewFile();

            PrintWriter out = new PrintWriter(new FileWriter(file));
            out.println("SOME VALUES");
            out.close();

            saveMsgHandler(file.getAbsolutePath());
        } catch (Exception e) {
            saveMsgHandler(null);
        }
    }

    @Override
    public void onBackPressed() {
        return;
    }

    private void saveMsgHandler(String savePath){
        if (savePath == null) {
            msg.setText(R.string.could_not_save_settings);
            int errorColor = ContextCompat.getColor(this, R.color.error);
            msg.setBackgroundColor(errorColor);
        } else {
            String string = String.format(getString(R.string.save_success),savePath);
            msg.setText(string);
            int success = ContextCompat.getColor(this, R.color.success);
            msg.setBackgroundColor(success);
        }
        msg.setVisibility(View.VISIBLE);
        this.saveIntoFile.setEnabled(true);
    }

    private void permissionSaveDenied(){
        msg.setVisibility(View.VISIBLE);
        msg.setText(R.string.could_not_save_settings);
        int errorColor = ContextCompat.getColor(this, R.color.error);
        msg.setBackgroundColor(errorColor);
        this.saveIntoFile.setEnabled(true);
    }

    @Override
    public void onClick(View v) {
        if (ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED) {
            Log.d("H300s","Permission Accepted");
            saveFile();
        } else {
            requestPermissionLauncher.launch(Manifest.permission.WRITE_EXTERNAL_STORAGE );
        }
    }
}

And I want once I save the file to be able to prompt into androids file manager and list the saved file. Any provided solution tells me hot to select a path before saving as seen in this answer or in this question , but instead I want just to show the file into device's file manager after I successfully saving it.

So far, what I've developed is this method:

public void displayFileIntoFileManager(String path){
        Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
        intent.setType("*/*");
        startActivity(intent, 7);
}

As a method to call from a button, once I saved the file in saveFile method. But how I can provide the path to the intent in order to be shown?

I just want to list the file into device's file manager.

Answer 1

I want just to show the file into device's file manager after I successfully saving it.

There is no standard Intent action for "open a file manager on a directory containing a specific file", sorry.

So far, what I've developed is this method

ACTION_GET_CONTENT is to allow the user to select a piece of content. If you are not looking to have the user do that, then this is not a suitable Intent action.

Answer 2

How I can prompt a file manager into a known path in an android app?

Wrong question.

You should have asked:

How can i let ACTION_GET_CONTENT, ACTION_OPEN_DOCUMENT and ACTION_OPEN_DOCUMENT_TREE open in a pre determined directory?

That question has been answered before.

The trick is to use extra INITIAL_URI .