Tempo locking controls

[FrankwaP]

This PR adds controls for tempo locking (tempo_lock) and unlocking (locking) so they can be used through keyboard shortcuts or MIDI inputs,a s suggested in 13038.

[ronso0]

Thanks for this PR!

Since this is a deck control we should eep it simple and have just one control:
bpm_toggle_lock
This will also allow to simplify the slots. You can get the track's lock state with Track::isBpmLocked().
"bpm" because "tempo" refers to the playback speed.

In case this shall be adopted for the library later on we will also make do with just one control, even if multiple tracks with locked/unlocked are selected:

• all the same lock state: toggle lock
• different lock state: lock all, trigger again to unlock all

[ronso0]

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Thanks!

[ronso0]

Since this is a deck control we should eep it simple and have just one control:
bpm_toggle_lock

In case you adopt this you may very well create a fixup commit, squash all (the 4) commits and force-push.

[ronso0]

Thank, this is much cleaner now.

Some comments though

[ronso0]

Thanks, I'll try this next days.

[ronso0]

(feel free to ping me in case this slips off my table ; )

[ronso0]

perfecto, LGTM

[ronso0]

FYI review conversations are resolved by reviewers only (and when the contributor picks a code suggestion :| ). Otherwise it's tedious for reviewers to check whether all comments have been addressed.

[ronso0]

Thank you!

Can you please take care of the documentation in https://manual.mixxx.org/2.5/chapters/appendix/mixxx_controls.html ?

[ronso0]

In case this shall be adopted for the library later on we will also make do with just one control, even if multiple tracks with locked/unlocked are selected:

* all the same lock state: toggle lock

* different lock state: lock all, trigger again to unlock all

If you want to work on that, too, note that the control flow is a bit more elaborate:
LibraryControl
-> m_pLibraryWidget
-> active view: must be a WTrackTableView
-> toggleBpmLockOfSelectedTracks

you may also take a loot at the helper WTrackMenu::getTrackBpmLockStates()

[FrankwaP]

Thank you!

Can you please take care of the documentation in https://manual.mixxx.org/2.5/chapters/appendix/mixxx_controls.html ?

Please see: mixxxdj/manual#637

[FrankwaP]

In case this shall be adopted for the library later on we will also make do with just one control…

I'm not sure I understand: how is it supposed to be different from the command which toggles lock/unlock when clicking the lock icon in the track field?

BTW I've just discover the "auto unlock" when one selects a locked track with no BPM. This feels super weird, like it's a bug… why not preventing from locking in the first place?

[ronso0]

I'm not sure I understand: how is it supposed to be different from the command which toggles lock/unlock when clicking the lock icon in the track field?

It would toggle lock for all selected tracks at once.
That control probably doesn't make much sense for the 'controller only' workflow (selecting multiple tracks still requires pressing Shift on the keyboard), but --considering the track management controls that were requested/implemented recently-- it might make sense for 'mouse + keyboard' and 'controller + keyboard' workflows: Tracks knobs usually send key Up/Down controls to the focused widget and holding Shift on the keyboard meanwhile is possible.
(theoretically, need to test this)

[daschuer]

@FrankwaP Thank you for your contributions. I would like to add you to the contributor list at the Mixxx about box. Shall I use your full name or a nick name?

[FrankwaP]

Thank you for taking time to explain the logic for the multi-track toggle :-)
I will look into it next week. Have a great day!

I would like to add you to the contributor list at the Mixxx about box. Shall I use your full name or a nick name?

Thanks for the attention :-) you can use FrankwaP.