How to write into a file picked by user in Android 12

Question

I encounter a problem only on Android 12, I try to add some lines into a file localized in a folder that the user pick. I worked on a Samsung A70 (Android 11), and to accomplish that I launch an Intent.ACTION_OPEN_DOCUMENT_TREE, check all to have to be checked (not null, file existing etc).

After that, i launch an getContentResolver().takePersistableUriPermission(data.getData(), Intent.FLAG_GRANT_WRITE_URI_PERMISSION | Intent.FLAG_GRANT_READ_URI_PERMISSION); to keep the permission.

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And this is working on the Samsung A70, but I need this in my Samsung S22 (Android 12) too, but it doesn't work.

I got an java.io.FileNotFoundException: Failed to open for writing: java.io.FileNotFoundException: open failed: EACCES (Permission denied) when trying to write something.

What i try:

I decide to change to an Intent.ACTION_OPEN_DOCUMENT to pick only the file i need, take a persistant permission too, but again this error.

I try to print all files access into the folder that the user picked:

DocumentFile dir = DocumentFile.fromTreeUri(this, data.getData());
            
if(null != dir){
   for(DocumentFile d : dir.listFiles()){
        System.out.println(d.getName() + "> Access: (R/W) " + d.canRead() + " - " + d.canWrite());
   }
}

And I got this with Android 12:S22 logcat of the function above

And this on Android 11: A70 logcat of the function above

With the same code.

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The file I need to write on is the json file (hardware[...].json)

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In the Android Doc I saw that the canWrite methods can return true, even though my app cannot write into, so they recommended to query the flag FLAG_SUPPORTS_WRITE directly, what i done:

try{
      System.out.println(data.getFlags());
      System.out.println(data.getFlags() & DocumentsContract.Document.FLAG_SUPPORTS_WRITE);
      ParcelFileDescriptor pfd = getContentResolver().openFileDescriptor(data.getData(), "w"); //Error here
      FileOutputStream fos = new FileOutputStream(pfd.getFileDescriptor());

      fos.close();
}catch//***//

And got this into the logcat (Android 12): logcat test flags android 12

And on Android 11: logcat test flags android 11

The first value is 0b1000011, the FLAG_SUPPORTS_WRITE value is 0b10 (1 << 1) (Doc) So the second print is 2, showing that the flag is ok. But the line after, an error is throwed.

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That all, if anyone have an idea to solve this problem with me, thank you! :D