Dialog
Dialogs can be raised by libvlc for network actions and logins.
You may only call once PostLogin or PostAction or Dismiss after which this instance will be invalid.
Dismiss a dialog.
After this call, this instance won't be valid anymore
Post a question answer.
After this call, this instance won't be valid anymore
QuestionCb
Post a login answer.
After this call, the instance won't be valid anymore