Setting user's profile picture when signing up to parse.com

I am trying to allow the user to choose picture and set it as his/her profile picture when signing up.

I used the following code to convert the file and to sign up the user but it throw an exception when signing up:

final ParseUser user = new ParseUser(); user.setUsername(username); user.setPassword(password); user.setEmail(email);

    Toast.makeText(SignUpActivity.this, "setting the file ", Toast.LENGTH_LONG).show();

    byte[] fileByte = FileHelper.getByteArrayFromFile(this, mMediaUri);
    if(fileByte == null){
        Log.e(TAG, "The file is null");
    }else{
        if (mFileType.equals(ParseConstant.TYPE_IMAGE)){
            fileByte = FileHelper.reduceImageForUpload(fileByte);
        }
        String fileName = FileHelper.getFileName(this, mMediaUri, mFileType);
        file = new ParseFile(fileName, fileByte);
         user.put(ParseConstant.KEY_FILE, file);
    }

user.signUpInBackground(new SignUpCallback() { @Override public void done(ParseException e) { if (e == null) { navigateToHomePage(); } else { Toast.makeText(SignUpActivity.this, "Error in sign up ", Toast.LENGTH_LONG).show(); } } });

I also tried to save the file first and then add it to the user and sign up, this time it does not throw an exception, but when I check the Parse.com I don't see any change in the data. The file is not showing in the table.

Thanks in advance.