fix addButton crash in a specific behavior
How to reproduce this bug:
- open app;
- open Create Torrent Dialog;
- Click the add button directly；
- crash; because of the File Or Dir Path have not selected.
so, I add some code to fix this bug and add one string for error notice.
Your project is great!
by the way, I fixed a translate issus: string: creating_torrent_progress: fix …；to …