Android (Java) - Open a file stored in Downloads/Documents

Question

I want to directly open existing file stored in /Downloads

File will have specific name "terminal_config.json" and will be either local or on SD card.

Path should be like, but I think that's device specific and I cannot explicitly use this (instead use environment variable like "documents"): /storage/emulated/0/Documents/terminal_config.json

How can I do that?

Answer 1

This is the working code. Thank you for cooperation.

---

Add this to AndroidManifest.xml

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<application .........
    android:requestLegacyExternalStorage="true">

---

    // will ask for permissions if needed, even though they
    // are in AndroidManifest.xml already
    verifyStoragePermissions(MainActivity.this);

    File file = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS), "terminal_config.json");
    Uri path = Uri.fromFile(file);
    Log.w(null, "XXXFILE"+file);

    try  {
        Log.w(null, "READ:"+getStringFromFile(file));
    }
   catch (Exception e) {
        Log.d("ERR_FILE", e.toString());
    }

And then I copied these functions:

public static String convertStreamToString(InputStream is) throws Exception {
    BufferedReader reader = new BufferedReader(new InputStreamReader(is));
    StringBuilder sb = new StringBuilder();
    String line = null;
    while ((line = reader.readLine()) != null) {
        sb.append(line).append("\n");
    }
    reader.close();
    return sb.toString();
}

public static String getStringFromFile (File fl) throws Exception {
    FileInputStream fin = new FileInputStream(fl);
    String ret = convertStreamToString(fin);
    fin.close();
    return ret;
}


public static void verifyStoragePermissions(Activity activity) {
    // Check if we have write permission
    int permission = ActivityCompat.checkSelfPermission(activity, Manifest.permission.WRITE_EXTERNAL_STORAGE);

    if (permission != PackageManager.PERMISSION_GRANTED) {
        // We don't have permission so prompt the user
        ActivityCompat.requestPermissions(
                activity,
                PERMISSIONS_STORAGE,
                REQUEST_EXTERNAL_STORAGE
        );
    }
}