[Audacity-devel] Keyboard shortcuts for blind users

[<smu...@ob...>]

I had a 3-day car ride over the holidays, and used part of the time to ad=
d some
primitive keyboard functionality to Audacity.  These were done before som=
e of
great suggestions appeared here, so they do not take them into account.  =
Note
that any keyboard shortcuts can be changed in the preferences, and so it =
would
be good (once test builds get made) for interested parties to try out dif=
ferent
keyboard combos and find a nice useable set.

Overview:  These changes mainly add ways to interact with track objects u=
sing
the keyboard alone.  They are based on a 'cycle-tracks' function that cha=
nges
the selected track, using the tab key.  Only a single track will be selec=
ted;
the first track after the first currently-selected track.  The keyboard
shortcuts will operate on the first selected track.  =20

Technical details: =20
The current TrackPanel is just a big drawing palette where things are dra=
wn, and
mouse interactions are calculated programmatically.  A dream for the futu=
re is
to have these object-oriented, managing and drawing themselves, but that =
gets
increasingly difficult as the application gets more complex.  So, current=
ly
there are functions that operate the controls based essentially on the po=
sition
of mouse clicks on the trackpanel.  This made keyboard-based interactions
difficult to hook into these functions, because they were tied intimately=
 to the
location of the mouse. =20

I added a new set of trackpanel methods that take a track as an argument,
perhaps eventually ending up as methods of the  track-based classes.  Whe=
re
possible and not too difficult, I let made the mouse-based interaction fu=
nctions
use these new methods.  Hopefully this gets us a step closer to an eventu=
al
refactoring that will make trackpanel much cleaner and simpler.


New changes enhancing keyboard interaction:

Set Selection:

Ctrl-R: Set right selection.  When playing/recording, sets right
        selection to indicator position.  When not playing/recording,
        opens a dialog in which time of selection can be entered manually=
.

Ctrl-L: Set left selection.  When playing/recording, sets left
        selection to indicator position.  When not playing/recording,
        opens a dialog in which time of selection can be entered manually=
.


Tab:   Cycles tracks.  Finds first selected track and selects=20
       first track that follows it, deselecting all other tracks.

Accessing track label controls: =20
      The following keyboard combos operate controls on the first selecte=
d
      track.

Shift-M: Opens track menu
Shift-U: mUtes track
Shift-P: Opens dialog to set pan
Shift-G: Opens dialog to set gain
Shift-C: Closes track


  =20