Unable to Delete File in my File Manager app

Question

I am an Android Studio app dev. I am a beginner and making a file manager app and having some problems in allowing user to delete a file. The code is in java.

I already have permissions in manifest and have taken runtime permissions.

I have already tried code like .delete(); and Boolean temp = File.delete();
In these methods it gave warning that it will be ignored

This is my current code:

        final Button delete = findViewById(R.id.b1);

        delete.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                final AlertDialog.Builder deleteDialog = new AlertDialog.Builder(MainActivity.this);
                deleteDialog.setTitle("Delete");
                deleteDialog.setMessage("Do you really want to delete it?");
                deleteDialog.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        for (int i = 0; i < files.length; i++) {
                            if (selection[i]) {
                                deleteFileOrFolder(files[i]);
                            }
                        }
                        files = dir.listFiles();
                        filesFoundCount = files.length;
                        filesList.clear();

                        for (int i = 0; i < filesFoundCount; i++) {
                            filesList.add(files[i].getAbsolutePath());
                        }
                        textAdapter1.setData(filesList);

                    }
                });

                deleteDialog.setNegativeButton("No", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.cancel();
                    }
                });

                deleteDialog.show();
            }
        });

        isFileManagerInitialised = true;
    }
}

    private void deleteFileOrFolder(File FileOrFolder) {
    boolean isSuccess = false;
    if (FileOrFolder.isDirectory()) {
        if (FileOrFolder.list().length == 0) {
            isSuccess = FileOrFolder.delete();
            delete(getApplicationContext(), FileOrFolder);
        } else {
            String files[] = FileOrFolder.list();
            for (String temp : files) {
                File fileToDelete = new File(FileOrFolder, temp);
                deleteFileOrFolder(fileToDelete);
            }
            if (FileOrFolder.list().length == 0) {
                isSuccess = FileOrFolder.delete();
                delete(getApplicationContext(), FileOrFolder);
            }
        }
    } else {
        isSuccess = FileOrFolder.delete();
        delete(getApplicationContext(), FileOrFolder);
    }
}


public static boolean delete(final Context context, final File file) {
    final String where = MediaStore.MediaColumns.DATA + "=?";
    final String[] selectionArgs = new String[]{
            file.getAbsolutePath()
    };
    final ContentResolver contentResolver = context.getContentResolver();
    final String rootPath = String.valueOf(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS));

    contentResolver.delete(Uri.parse(rootPath), where, selectionArgs);

    if (file.exists()) {

        contentResolver.delete(Uri.parse(rootPath), where, selectionArgs);
    }
    return !file.exists();
}

The problem with it currently is that it is crashing on deleting and it does not delete on opening again.

LogCat: --------- beginning of crash 2020-09-01 19:15:52.146 9248-9248/com.example.file_manager E/AndroidRuntime: FATAL EXCEPTION: main Process: com.example.file_manager, PID: 9248 java.lang.IllegalArgumentException: Unknown URL /storage/emulated/0/Download at android.content.ContentResolver.delete(ContentResolver.java:2278) at android.content.ContentResolver.delete(ContentResolver.java:2248) at com.example.filemanager.MainActivity.delete(MainActivity.java:287) at com.example.filemanager.MainActivity.deleteFileOrFolder(MainActivity.java:262) at com.example.filemanager.MainActivity.access$200(MainActivity.java:35) at com.example.filemanager.MainActivity$2$1.onClick(MainActivity.java:213)

Can someone tell me how to delete the file?

Can someone please help me for I am doing this for a hackathon and need it by today 1 september 2020, so if you come across please answer