Checkboxes instead of radio buttons in ‘Add to playlist’ window

[casperdewith]

Checklist

• I made sure that there are no existing issues - open or closed - to which I could contribute my information.
• I made sure that there are no existing discussions - open or closed - to which I could contribute my information.
• I have read the FAQs inside the app (Menu -> About -> FAQs) and my problem isn't listed.
• I have taken the time to fill in all the required details. I understand that the request will be dismissed otherwise.
• This issue contains only one feature request.
• I have read and understood the contribution guidelines.

Feature description

When selecting tracks and adding them to a playlist, the ‘Add to playlist’ window currently consists of a simple radio-button list of my playlists. I cannot see which playlists already contain the tracks, nor can I add the selected tracks to multiple playlists in one go.

This is the solution that I have in mind:

1. The radio buttons should become checkboxes, so that I can select multiple playlists.
2. These checkboxes indicate which playlists currently contain the selected tracks.
   • If some playlist contains none of the selected tracks, its checkbox starts off as unchecked.
   • If some playlist contains all of the selected tracks, its checkbox starts off as checked.
   • If some playlist contains only some subset of the selected tracks, its checkbox starts off with a minus sign in it. This checkbox then becomes a three-way toggle between ‘include all’, ‘include original subset’ and ‘include none’.
3. The ‹Create new playlist…› option is a button that adds a new, checked item to the list. After the new playlist’s name is entered, the playlist-selection window stays open. This way, more playlists can be selected, or another new playlist can be created.
4. Add an ‹OK› button to confirm the addition or removal operations. This should be the only way to confirm the operations.
5. Add a ‹Cancel› button to cancel all operations. Tapping next to the window should do the same thing.

Why do you want this feature?

• I sometimes want to add a selection of tracks to multiple playlists at once. Currently, I have to select the tracks, add them to one playlist, reselect all of them, add them to a second playlist, etc.
• It is currently impossible to see what playlists the tracks are already in. This is a little frustrating.

Additional information

No response