Problem was that cfd7648fce2388ec8ae35b38004f2ae111c484af fixed a memory leak
but created a dangling pointer bug, which does not happen during usual run
of Audacity because AudacityProject::OnCloseWindow is reached then before
destroying AudacityProject.
Fixed it by using a std::shared_pointer for the TrackList that both
AudacityProject and TrackPanel must use.
The function builds pop up menus that are never displayed and
creates runtime debug warnings. It is left over from PRL's experiment
in 2.1.2 with a context menu for the vertical ruler.
... See comments #1 and #2 at
http://bugzilla.audacityteam.org/show_bug.cgi?id=1331
Don't make strange undo history if, e.g., R to record (or other keystroke
with undoable effects) interrupts a drag with undoable effects (like time
shift). Ensure that by first simulating a mouse button up event to stop the
drag, before dispatching the keystroke.
Don't crash if certain other drags, that do not have undoable effects, such
as selection or vertical ruler drag -- are interrupted by a keystroke
command (Ctrl+C in particular could cause crash). However, in these cases,
the drag is still allowed to continue.
... activated by clicking near the left end of the ruler, then using the
context menu.
This is not finished work, but a proof of concept for a possible new scrubbing
UI.
... So it does not depend on the focused window, and can work when selection
toolbar has focus. But TrackPanel's escape handling may still take precedence
over it.
... for functions in final classes.
override is like const -- it's not necessary, but it helps the compiler to
catch mistakes.
There may be some overriding functions not explicitly declared virtual and I did
not identify such cases, in which I might also add override.
... Should have no effect on generated code, except perhaps some slight faster
virtual function calls. Mostly useful as documentation of design intent.
Tried to mark every one of our classes that inherits from another, or is a
base for others, or has abstract virtual functions, and a few others besides.
... When you click in a stereo clip, move the correct partner clip with it.
When you click in the selection and it spans clips, move all clips containing
any part of the selection. (As horizontal dragging does.) Even if these are
not all within the same stereo track.
I implemented this rule: If any clip moves up (or down) by n audio tracks
(not counting the label tracks), all clips must move the same number, and
all must move from mono to mono or left to left or right to right. If that
is not possible, no move happens.
