Define class SelectionState; move some TrackPanel functions into it

mac/Audacity.xcodeproj/project.pbxproj

@@ -1208,6 +1208,7 @@
 		5E07842E1DEE6B8600CA76EA /* FileException.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 5E07842C1DEE6B8600CA76EA /* FileException.cpp */; };
 		5E0784311DF1E4F400CA76EA /* UserException.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 5E07842F1DF1E4F400CA76EA /* UserException.cpp */; };
 		5E0A0E311D23019A00CD2567 /* MenusMac.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 5E0A0E301D23019A00CD2567 /* MenusMac.cpp */; };
+		5E2A19941EED688500217B58 /* SelectionState.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 5E2A19921EED688500217B58 /* SelectionState.cpp */; };
 		5E74D2E31CC4429700D88B0B /* EditCursorOverlay.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 5E74D2DD1CC4429700D88B0B /* EditCursorOverlay.cpp */; };
 		5E74D2E41CC4429700D88B0B /* PlayIndicatorOverlay.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 5E74D2DF1CC4429700D88B0B /* PlayIndicatorOverlay.cpp */; };
 		5E74D2E51CC4429700D88B0B /* Scrubbing.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 5E74D2E11CC4429700D88B0B /* Scrubbing.cpp */; };
@@ -2988,6 +2989,8 @@
 		5E07842F1DF1E4F400CA76EA /* UserException.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = UserException.cpp; sourceTree = "<group>"; };
 		5E0784301DF1E4F400CA76EA /* UserException.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = UserException.h; sourceTree = "<group>"; };
 		5E0A0E301D23019A00CD2567 /* MenusMac.cpp */ = {isa = PBXFileReference; explicitFileType = sourcecode.cpp.objcpp; fileEncoding = 4; path = MenusMac.cpp; sourceTree = "<group>"; };
+		5E2A19921EED688500217B58 /* SelectionState.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = SelectionState.cpp; sourceTree = "<group>"; };
+		5E2A19931EED688500217B58 /* SelectionState.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SelectionState.h; sourceTree = "<group>"; };
 		5E4685F81CCA9D84008741F2 /* CommandFunctors.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = CommandFunctors.h; sourceTree = "<group>"; };
 		5E61EE0C1CBAA6BB0009FCF1 /* MemoryX.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = MemoryX.h; sourceTree = "<group>"; };
 		5E74D2D91CC4427B00D88B0B /* TrackPanelCell.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = TrackPanelCell.h; sourceTree = "<group>"; };
@@ -3909,6 +3912,7 @@
 				1790B0D609883BFD008A330A /* SampleFormat.cpp */,
 				285DE1F80BF03C7800A20DF0 /* Screenshot.cpp */,
 				28D8425B1AD8D69D00551353 /* SelectedRegion.cpp */,
+				5E2A19921EED688500217B58 /* SelectionState.cpp */,
 				1790B0DA09883BFD008A330A /* Sequence.cpp */,
 				1790B0DC09883BFD008A330A /* Shuttle.cpp */,
 				283A11A60A2C0E15004372C4 /* ShuttleGui.cpp */,
@@ -4005,6 +4009,7 @@
 				1790B0D709883BFD008A330A /* SampleFormat.h */,
 				285DE1F90BF03C7800A20DF0 /* Screenshot.h */,
 				2813897919E6163C004111ED /* SelectedRegion.h */,
+				5E2A19931EED688500217B58 /* SelectionState.h */,
 				1790B0DB09883BFD008A330A /* Sequence.h */,
 				1790B0DD09883BFD008A330A /* Shuttle.h */,
 				283A11A70A2C0E15004372C4 /* ShuttleGui.h */,
@@ -7472,6 +7477,7 @@
 				1790B1A709883BFD008A330A /* Warning.cpp in Sources */,
 				1790B1A909883BFD008A330A /* XMLFileReader.cpp in Sources */,
 				1790B1AA09883BFD008A330A /* XMLTagHandler.cpp in Sources */,
+				5E2A19941EED688500217B58 /* SelectionState.cpp in Sources */,
 				17190D24098A3F0B004583C6 /* AColor.cpp in Sources */,
 				17190D25098A3F15004583C6 /* AboutDialog.cpp in Sources */,
 				174D9031098C78AF00D5909F /* CommandManager.cpp in Sources */,

src/Makefile.am

@@ -206,6 +206,8 @@ audacity_SOURCES = \
 	Screenshot.h \
 	SelectedRegion.cpp \
 	SelectedRegion.h \
+	SelectionState.cpp \
+	SelectionState.h \
 	Shuttle.cpp \
 	Shuttle.h \
 	ShuttleGui.cpp \

src/Makefile.in

@@ -315,8 +315,9 @@ am__audacity_SOURCES_DIST = BlockFile.cpp BlockFile.h DirManager.cpp \
 	RealFFTf.h RealFFTf48x.cpp RealFFTf48x.h Resample.cpp \
 	Resample.h RevisionIdent.h RingBuffer.cpp RingBuffer.h \
 	Screenshot.cpp Screenshot.h SelectedRegion.cpp \
-	SelectedRegion.h Shuttle.cpp Shuttle.h ShuttleGui.cpp \
+	SelectedRegion.h SelectionState.cpp SelectionState.h \
-	ShuttleGui.h ShuttlePrefs.cpp ShuttlePrefs.h Snap.cpp Snap.h \
+	Shuttle.cpp Shuttle.h ShuttleGui.cpp ShuttleGui.h \
+	ShuttlePrefs.cpp ShuttlePrefs.h Snap.cpp Snap.h \
 	SoundActivatedRecord.cpp SoundActivatedRecord.h Spectrum.cpp \
 	Spectrum.h SplashDialog.cpp SplashDialog.h SseMathFuncs.cpp \
 	SseMathFuncs.h Tags.cpp Tags.h Theme.cpp Theme.h \
@@ -575,7 +576,8 @@ am_audacity_OBJECTS = $(am__objects_1) audacity-AboutDialog.$(OBJEXT) \
 	audacity-RealFFTf.$(OBJEXT) audacity-RealFFTf48x.$(OBJEXT) \
 	audacity-Resample.$(OBJEXT) audacity-RingBuffer.$(OBJEXT) \
 	audacity-Screenshot.$(OBJEXT) \
-	audacity-SelectedRegion.$(OBJEXT) audacity-Shuttle.$(OBJEXT) \
+	audacity-SelectedRegion.$(OBJEXT) \
+	audacity-SelectionState.$(OBJEXT) audacity-Shuttle.$(OBJEXT) \
 	audacity-ShuttleGui.$(OBJEXT) audacity-ShuttlePrefs.$(OBJEXT) \
 	audacity-Snap.$(OBJEXT) \
 	audacity-SoundActivatedRecord.$(OBJEXT) \
@@ -1018,6 +1020,8 @@ PACKAGE_URL = @PACKAGE_URL@
 PACKAGE_VERSION = @PACKAGE_VERSION@
 PATH_SEPARATOR = @PATH_SEPARATOR@
 PKG_CONFIG = @PKG_CONFIG@
+PKG_CONFIG_LIBDIR = @PKG_CONFIG_LIBDIR@
+PKG_CONFIG_PATH = @PKG_CONFIG_PATH@
 PORTAUDIO_CFLAGS = @PORTAUDIO_CFLAGS@
 PORTAUDIO_LIBS = @PORTAUDIO_LIBS@
 PORTMIXER_LIBS = @PORTMIXER_LIBS@
@@ -1095,7 +1099,6 @@ pdfdir = @pdfdir@
 prefix = @prefix@
 program_transform_name = @program_transform_name@
 psdir = @psdir@
-runstatedir = @runstatedir@
 sbindir = @sbindir@
 sharedstatedir = @sharedstatedir@
 srcdir = @srcdir@
@@ -1219,8 +1222,9 @@ audacity_SOURCES = $(libaudacity_la_SOURCES) AboutDialog.cpp \
 	RealFFTf.h RealFFTf48x.cpp RealFFTf48x.h Resample.cpp \
 	Resample.h RevisionIdent.h RingBuffer.cpp RingBuffer.h \
 	Screenshot.cpp Screenshot.h SelectedRegion.cpp \
-	SelectedRegion.h Shuttle.cpp Shuttle.h ShuttleGui.cpp \
+	SelectedRegion.h SelectionState.cpp SelectionState.h \
-	ShuttleGui.h ShuttlePrefs.cpp ShuttlePrefs.h Snap.cpp Snap.h \
+	Shuttle.cpp Shuttle.h ShuttleGui.cpp ShuttleGui.h \
+	ShuttlePrefs.cpp ShuttlePrefs.h Snap.cpp Snap.h \
 	SoundActivatedRecord.cpp SoundActivatedRecord.h Spectrum.cpp \
 	Spectrum.h SplashDialog.cpp SplashDialog.h SseMathFuncs.cpp \
 	SseMathFuncs.h Tags.cpp Tags.h Theme.cpp Theme.h \
@@ -2126,6 +2130,7 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/audacity-SampleFormat.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/audacity-Screenshot.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/audacity-SelectedRegion.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/audacity-SelectionState.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/audacity-Sequence.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/audacity-Shuttle.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/audacity-ShuttleGui.Po@am__quote@
@@ -3455,6 +3460,20 @@ audacity-SelectedRegion.obj: SelectedRegion.cpp
 @AMDEP_TRUE@@am__fastdepCXX_FALSE@	DEPDIR=$(DEPDIR) $(CXXDEPMODE) $(depcomp) @AMDEPBACKSLASH@
 @am__fastdepCXX_FALSE@	$(AM_V_CXX@am__nodep@)$(CXX) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(audacity_CPPFLAGS) $(CPPFLAGS) $(audacity_CXXFLAGS) $(CXXFLAGS) -c -o audacity-SelectedRegion.obj `if test -f 'SelectedRegion.cpp'; then $(CYGPATH_W) 'SelectedRegion.cpp'; else $(CYGPATH_W) '$(srcdir)/SelectedRegion.cpp'; fi`
 
+audacity-SelectionState.o: SelectionState.cpp
+@am__fastdepCXX_TRUE@	$(AM_V_CXX)$(CXX) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(audacity_CPPFLAGS) $(CPPFLAGS) $(audacity_CXXFLAGS) $(CXXFLAGS) -MT audacity-SelectionState.o -MD -MP -MF $(DEPDIR)/audacity-SelectionState.Tpo -c -o audacity-SelectionState.o `test -f 'SelectionState.cpp' || echo '$(srcdir)/'`SelectionState.cpp
+@am__fastdepCXX_TRUE@	$(AM_V_at)$(am__mv) $(DEPDIR)/audacity-SelectionState.Tpo $(DEPDIR)/audacity-SelectionState.Po
+@AMDEP_TRUE@@am__fastdepCXX_FALSE@	$(AM_V_CXX)source='SelectionState.cpp' object='audacity-SelectionState.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCXX_FALSE@	DEPDIR=$(DEPDIR) $(CXXDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCXX_FALSE@	$(AM_V_CXX@am__nodep@)$(CXX) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(audacity_CPPFLAGS) $(CPPFLAGS) $(audacity_CXXFLAGS) $(CXXFLAGS) -c -o audacity-SelectionState.o `test -f 'SelectionState.cpp' || echo '$(srcdir)/'`SelectionState.cpp
+
+audacity-SelectionState.obj: SelectionState.cpp
+@am__fastdepCXX_TRUE@	$(AM_V_CXX)$(CXX) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(audacity_CPPFLAGS) $(CPPFLAGS) $(audacity_CXXFLAGS) $(CXXFLAGS) -MT audacity-SelectionState.obj -MD -MP -MF $(DEPDIR)/audacity-SelectionState.Tpo -c -o audacity-SelectionState.obj `if test -f 'SelectionState.cpp'; then $(CYGPATH_W) 'SelectionState.cpp'; else $(CYGPATH_W) '$(srcdir)/SelectionState.cpp'; fi`
+@am__fastdepCXX_TRUE@	$(AM_V_at)$(am__mv) $(DEPDIR)/audacity-SelectionState.Tpo $(DEPDIR)/audacity-SelectionState.Po
+@AMDEP_TRUE@@am__fastdepCXX_FALSE@	$(AM_V_CXX)source='SelectionState.cpp' object='audacity-SelectionState.obj' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCXX_FALSE@	DEPDIR=$(DEPDIR) $(CXXDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCXX_FALSE@	$(AM_V_CXX@am__nodep@)$(CXX) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(audacity_CPPFLAGS) $(CPPFLAGS) $(audacity_CXXFLAGS) $(CXXFLAGS) -c -o audacity-SelectionState.obj `if test -f 'SelectionState.cpp'; then $(CYGPATH_W) 'SelectionState.cpp'; else $(CYGPATH_W) '$(srcdir)/SelectionState.cpp'; fi`
+
 audacity-Shuttle.o: Shuttle.cpp
 @am__fastdepCXX_TRUE@	$(AM_V_CXX)$(CXX) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(audacity_CPPFLAGS) $(CPPFLAGS) $(audacity_CXXFLAGS) $(CXXFLAGS) -MT audacity-Shuttle.o -MD -MP -MF $(DEPDIR)/audacity-Shuttle.Tpo -c -o audacity-Shuttle.o `test -f 'Shuttle.cpp' || echo '$(srcdir)/'`Shuttle.cpp
 @am__fastdepCXX_TRUE@	$(AM_V_at)$(am__mv) $(DEPDIR)/audacity-Shuttle.Tpo $(DEPDIR)/audacity-Shuttle.Po

src/SelectionState.cpp

@@ -0,0 +1,190 @@
+/**********************************************************************
+
+ Audacity: A Digital Audio Editor
+
+ SelectionState.h
+
+ **********************************************************************/
+
+#include "Audacity.h"
+#include "SelectionState.h"
+#include "MixerBoard.h"
+#include "ViewInfo.h"
+#include "Track.h"
+
+// Set selection length to the length of a track -- but if sync-lock is turned
+// on, use the largest possible selection in the sync-lock group.
+// If it's a stereo track, do the same for the stereo channels.
+void SelectionState::SelectTrackLength
+( TrackList &tracks, ViewInfo &viewInfo, Track &track, bool syncLocked )
+{
+   SyncLockedTracksIterator it( &tracks );
+   Track *t1 = it.StartWith( &track );
+   double minOffset = track.GetOffset();
+   double maxEnd = track.GetEndTime();
+
+   // If we have a sync-lock group and sync-lock linking is on,
+   // check the sync-lock group tracks.
+   if ( syncLocked && t1 != NULL )
+   {
+      for ( ; t1; t1 = it.Next())
+      {
+         if (t1->GetOffset() < minOffset)
+            minOffset = t1->GetOffset();
+         if (t1->GetEndTime() > maxEnd)
+            maxEnd = t1->GetEndTime();
+      }
+   }
+   else
+   {
+      // Otherwise, check for a stereo pair
+      t1 = track.GetLink();
+      if (t1)
+      {
+         if (t1->GetOffset() < minOffset)
+            minOffset = t1->GetOffset();
+         if (t1->GetEndTime() > maxEnd)
+            maxEnd = t1->GetEndTime();
+      }
+   }
+
+   // PRL: double click or click on track control.
+   // should this select all frequencies too?  I think not.
+   viewInfo.selectedRegion.setTimes(minOffset, maxEnd);
+}
+
+void SelectionState::SelectTrack
+( TrackList &tracks, Track &track, bool selected, bool updateLastPicked,
+  MixerBoard *pMixerBoard )
+{
+   bool wasCorrect = (selected == track.GetSelected());
+
+   tracks.Select( &track, selected );
+   if (updateLastPicked)
+      mLastPickedTrack = &track;
+
+//The older code below avoids an anchor on an unselected track.
+
+   /*
+   if (selected) {
+      // This handles the case of linked tracks, selecting all channels
+      mTracks->Select(pTrack, true);
+      if (updateLastPicked)
+         mLastPickedTrack = pTrack;
+   }
+   else {
+      mTracks->Select(pTrack, false);
+      if (updateLastPicked && pTrack == mLastPickedTrack)
+         mLastPickedTrack = nullptr;
+   }
+*/
+
+   // Update mixer board, but only as needed so it does not flicker.
+   if (!wasCorrect) {
+      auto pt = dynamic_cast< PlayableTrack* >( &track );
+      if (pMixerBoard && pt)
+         pMixerBoard->RefreshTrackCluster( pt );
+   }
+}
+
+void SelectionState::SelectRangeOfTracks
+( TrackList &tracks, Track &rsTrack, Track &reTrack, MixerBoard *pMixerBoard )
+{
+   Track *sTrack = &rsTrack, *eTrack = &reTrack;
+   // Swap the track pointers if needed
+   if (eTrack->GetIndex() < sTrack->GetIndex())
+      std::swap(sTrack, eTrack);
+
+   TrackListIterator iter( &tracks );
+   sTrack = iter.StartWith( sTrack );
+   do {
+      SelectTrack( tracks, *sTrack, true, false, pMixerBoard );
+      if ( sTrack == eTrack ) {
+         break;
+      }
+
+      sTrack = iter.Next();
+   } while ( sTrack );
+}
+
+void SelectionState::SelectNone( TrackList &tracks, MixerBoard *pMixerBoard )
+{
+   TrackListIterator iter( &tracks );
+   Track *track = iter.First();
+   while ( track ) {
+      SelectTrack( tracks, *track, false, false, pMixerBoard );
+      track = iter.Next();
+   }
+}
+
+void SelectionState::ChangeSelectionOnShiftClick
+( TrackList &tracks, Track &track, MixerBoard *pMixerBoard )
+{
+
+   // Optional: Track already selected?  Nothing to do.
+   // If we enable this, Shift-Click behaves like click in this case.
+   //if( pTrack->GetSelected() )
+   //   return;
+
+   // Find first and last selected track.
+   Track* pFirst = nullptr;
+   Track* pLast = nullptr;
+   // We will either extend from the first or from the last.
+   Track* pExtendFrom= nullptr;
+
+   if( mLastPickedTrack )
+      pExtendFrom = mLastPickedTrack;
+   else {
+      TrackListIterator iter( &tracks );
+      for (Track *t = iter.First(); t; t = iter.Next()) {
+         const bool isSelected = t->GetSelected();
+         // Record first and last selected.
+         if( isSelected ) {
+            if( !pFirst )
+               pFirst = t;
+            pLast = t;
+         }
+         // If our track is at or after the first, extend from the first.
+         if( t == &track )
+            pExtendFrom = pFirst;
+      }
+      // Our track was earlier than the first.  Extend from the last.
+      if( !pExtendFrom )
+         pExtendFrom = pLast;
+   }
+
+   SelectNone( tracks, pMixerBoard );
+   if( pExtendFrom )
+      SelectRangeOfTracks( tracks, track, *pExtendFrom, pMixerBoard );
+   else
+      SelectTrack( tracks, track, true, true, pMixerBoard );
+   mLastPickedTrack = pExtendFrom;
+}
+
+void SelectionState::HandleListSelection
+( TrackList &tracks, ViewInfo &viewInfo,
+  Track &track, bool shift, bool ctrl, bool syncLocked, MixerBoard *pMixerBoard )
+{
+   // AS: If the shift button is being held down, invert
+   //  the selection on this track.
+   if (ctrl)
+      SelectTrack( tracks, track, !track.GetSelected(), true, pMixerBoard );
+   else {
+      if (shift && mLastPickedTrack)
+         ChangeSelectionOnShiftClick( tracks, track, pMixerBoard );
+      else {
+         SelectNone( tracks, pMixerBoard );
+         SelectTrack( tracks, track, true, true, pMixerBoard );
+         SelectTrackLength( tracks, viewInfo, track, syncLocked );
+      }
+
+      if (pMixerBoard)
+         pMixerBoard->RefreshTrackClusters();
+   }
+}
+
+void SelectionState::TrackListUpdated( const TrackList &tracks )
+{
+   if (mLastPickedTrack && !tracks.Contains(mLastPickedTrack))
+      mLastPickedTrack = nullptr;
+}

src/SelectionState.h

@@ -0,0 +1,43 @@
+/**********************************************************************
+
+ Audacity: A Digital Audio Editor
+
+ SelectionState.h
+
+ **********************************************************************/
+
+#ifndef __AUDACITY_SELECTION_STATE__
+#define __AUDACITY_SELECTION_STATE__
+
+class Track;
+class TrackList;
+class MixerBoard;
+class ViewInfo;
+
+// State relating to the set of selected tracks
+class SelectionState
+{
+public:
+   static void SelectTrackLength
+      ( TrackList &tracks, ViewInfo &viewInfo, Track &track, bool syncLocked );
+
+   void SelectTrack
+      ( TrackList &tracks, Track &track,
+        bool selected, bool updateLastPicked, MixerBoard *pMixerBoard );
+   // Inclusive range of tracks, the limits specified in either order:
+   void SelectRangeOfTracks
+      ( TrackList &tracks, Track &sTrack, Track &eTrack,
+        MixerBoard *pMixerBoard );
+   void SelectNone( TrackList &tracks, MixerBoard *pMixerBoard );
+   void ChangeSelectionOnShiftClick
+      ( TrackList &tracks, Track &track, MixerBoard *pMixerBoard );
+   void HandleListSelection
+      ( TrackList &tracks, ViewInfo &viewInfo, Track &track,
+        bool shift, bool ctrl, bool syncLocked, MixerBoard *pMixerBoard );
+
+   void TrackListUpdated( const TrackList &tracks );
+
+   Track *mLastPickedTrack {};
+};
+
+#endif

src/TrackPanel.cpp

@@ -798,16 +798,6 @@ void TrackPanel::SetCapturedTrack( Track * t, enum MouseCaptureEnum MouseCapture
    mMouseCapture = MouseCapture;
 }
 
-void TrackPanel::SelectNone()
-{
-   TrackListIterator iter(GetTracks());
-   Track *t = iter.First();
-   while (t) {
-      SelectTrack(t, false, false);
-      t = iter.Next();
-   }
-}
-
 /// Select all tracks marked by the label track lt
 void TrackPanel::SelectTracksByLabel( LabelTrack *lt )
 {
@@ -825,52 +815,11 @@ void TrackPanel::SelectTracksByLabel( LabelTrack *lt )
    t = iter.First();
    while( t )
    {
-      SelectTrack(t, true);
+      GetSelectionState().SelectTrack( *mTracks, *t, true, true, GetMixerBoard() );
       t = iter.Next();
    }
 }
 
-// Set selection length to the length of a track -- but if sync-lock is turned
-// on, use the largest possible selection in the sync-lock group.
-// If it's a stereo track, do the same for the stereo channels.
-void TrackPanel::SelectTrackLength(Track *t)
-{
-   AudacityProject *p = GetActiveProject();
-   SyncLockedTracksIterator it(GetTracks());
-   Track *t1 = it.StartWith(t);
-   double minOffset = t->GetOffset();
-   double maxEnd = t->GetEndTime();
-
-   // If we have a sync-lock group and sync-lock linking is on,
-   // check the sync-lock group tracks.
-   if (p->IsSyncLocked() && t1 != NULL)
-   {
-      for ( ; t1; t1 = it.Next())
-      {
-         if (t1->GetOffset() < minOffset)
-            minOffset = t1->GetOffset();
-         if (t1->GetEndTime() > maxEnd)
-            maxEnd = t1->GetEndTime();
-      }
-   }
-   else
-   {
-      // Otherwise, check for a stereo pair
-      t1 = t->GetLink();
-      if (t1)
-      {
-         if (t1->GetOffset() < minOffset)
-            minOffset = t1->GetOffset();
-         if (t1->GetEndTime() > maxEnd)
-            maxEnd = t1->GetEndTime();
-      }
-   }
-
-   // PRL: double click or click on track control.
-   // should this select all frequencies too?  I think not.
-   mViewInfo->selectedRegion.setTimes(minOffset, maxEnd);
-}
-
 void TrackPanel::GetTracksUsableArea(int *width, int *height) const
 {
    GetSize(width, height);
@@ -1210,7 +1159,7 @@ bool TrackPanel::HandleEscapeKey(bool down)
          wxASSERT(it != end);
          t->SetSelected(*it++);
       }
-      mLastPickedTrack = mInitialLastPickedTrack;
+      GetSelectionState().mLastPickedTrack = mInitialLastPickedTrack;
       mViewInfo->selectedRegion = mInitialSelection;
 
       // Refresh mixer board for change of set of selected tracks
@@ -1899,12 +1848,14 @@ void TrackPanel::HandleSelect(wxMouseEvent & event)
       }
 
       // Deselect all other tracks and select this one.
-      SelectNone();
+      GetSelectionState().SelectNone( *mTracks, GetMixerBoard() );
 
-      SelectTrack(mCapturedTrack, true);
+      GetSelectionState().SelectTrack
+         ( *mTracks, *mCapturedTrack, true, true, GetMixerBoard() );
 
       // Default behavior: select whole track
-      SelectTrackLength(mCapturedTrack);
+      SelectionState::SelectTrackLength
+         ( *mTracks, *mViewInfo, *mCapturedTrack, GetProject()->IsSyncLocked() );
 
       // Special case: if we're over a clip in a WaveTrack,
       // select just that clip
@@ -1936,39 +1887,6 @@ void TrackPanel::HandleSelect(wxMouseEvent & event)
    SelectionHandleDrag(event, t);
 }
 
-void TrackPanel::SelectTrack(Track *pTrack, bool selected, bool updateLastPicked)
-{
-   bool wasCorrect = (selected == pTrack->GetSelected());
-
-   mTracks->Select(pTrack, selected);
-   if (updateLastPicked)
-      mLastPickedTrack = pTrack;
-
-//Thw older code below avoids an anchor on an unselected track.
-
-   /*
-   if (selected) {
-      // This handles the case of linked tracks, selecting all channels
-      mTracks->Select(pTrack, true);
-      if (updateLastPicked)
-         mLastPickedTrack = pTrack;
-   }
-   else {
-      mTracks->Select(pTrack, false);
-      if (updateLastPicked && pTrack == mLastPickedTrack)
-         mLastPickedTrack = nullptr;
-   }
-*/
-
-   // Update mixer board, but only as needed so it does not flicker.
-   if (!wasCorrect) {
-      MixerBoard* pMixerBoard = this->GetMixerBoard();
-      auto pt = dynamic_cast< PlayableTrack* >( pTrack );
-      if (pMixerBoard && pt)
-         pMixerBoard->RefreshTrackCluster( pt );
-   }
-}
-
 // Counts tracks, counting stereo tracks as one track.
 size_t TrackPanel::GetTrackCount(){
    size_t count = 0;
@@ -2001,71 +1919,6 @@ size_t TrackPanel::GetSelectedTrackCount(){
    return count;
 }
 
-void TrackPanel::SelectRangeOfTracks(Track *sTrack, Track *eTrack)
-{
-   if (eTrack) {
-      // Swap the track pointers if needed
-      if (eTrack->GetIndex() < sTrack->GetIndex())
-         std::swap(sTrack, eTrack);
-
-      TrackListIterator iter(GetTracks());
-      sTrack = iter.StartWith(sTrack);
-      do {
-         SelectTrack(sTrack, true, false);
-         if (sTrack == eTrack) {
-            break;
-         }
-
-         sTrack = iter.Next();
-      } while (sTrack);
-   }
-}
-
-void TrackPanel::ChangeSelectionOnShiftClick(Track * pTrack){
-
-   // Optional: Track already selected?  Nothing to do.
-   // If we enable this, Shift-Click behaves like click in this case.
-   //if( pTrack->GetSelected() )
-   //   return;
-
-   // Find first and last selected track.
-   Track* pFirst = nullptr;
-   Track* pLast = nullptr;
-   // We will either extend from the first or from the last.
-   Track* pExtendFrom= nullptr;
-
-   if( mLastPickedTrack ){
-      pExtendFrom = mLastPickedTrack;
-   }
-   else
-   {
-      TrackListIterator iter(GetTracks());
-      for (Track *t = iter.First(); t; t = iter.Next()) {
-         const bool isSelected = t->GetSelected();
-         // Record first and last selected.
-         if( isSelected ){
-            if( !pFirst )
-               pFirst = t;
-            pLast = t;
-         }
-         // If our track is at or after the first, extend from the first.
-         if( t == pTrack ){
-            pExtendFrom = pFirst;
-         }
-      }
-      // Our track was earlier than the first.  Extend from the last.
-      if( !pExtendFrom )
-         pExtendFrom = pLast;
-   }
-
-   SelectNone();
-   if( pExtendFrom )
-      SelectRangeOfTracks(pTrack, pExtendFrom);
-   else
-      SelectTrack( pTrack, true );
-   mLastPickedTrack = pExtendFrom;
-}
-
 /// This method gets called when we're handling selection
 /// and the mouse was just clicked.
 void TrackPanel::SelectionHandleClick(wxMouseEvent & event,
@@ -2078,7 +1931,7 @@ void TrackPanel::SelectionHandleClick(wxMouseEvent & event,
 
    mMouseCapture=IsSelecting;
    mInitialSelection = mViewInfo->selectedRegion;
-   mInitialLastPickedTrack = mLastPickedTrack;
+   mInitialLastPickedTrack = GetSelectionState().mLastPickedTrack;
 
    // Save initial state of track selections
    mInitialTrackSelection.clear();
@@ -2110,7 +1963,8 @@ void TrackPanel::SelectionHandleClick(wxMouseEvent & event,
    )) {
 
       if( bShiftDown )
-         ChangeSelectionOnShiftClick( pTrack );
+         GetSelectionState().ChangeSelectionOnShiftClick
+            ( *mTracks, *pTrack, GetMixerBoard() );
       if( bCtrlDown ){
          //Commented out bIsSelected toggles, as in Track Control Panel.
          //bool bIsSelected = pTrack->GetSelected();
@@ -2118,8 +1972,8 @@ void TrackPanel::SelectionHandleClick(wxMouseEvent & event,
          bool bIsSelected = false;
          // Don't toggle away the last selected track.
          if( !bIsSelected || GetSelectedTrackCount() > 1 )
-            SelectTrack( pTrack, !bIsSelected, true );
+            GetSelectionState().SelectTrack
-         mLastPickedTrack = pTrack;
+               ( *mTracks, *pTrack, !bIsSelected, true, GetMixerBoard() );
       }
 
       double value;
@@ -2333,12 +2187,13 @@ void TrackPanel::SelectionHandleClick(wxMouseEvent & event,
 #endif
    if (startNewSelection) {
       // If we didn't move a selection boundary, start a NEW selection
-      SelectNone();
+      GetSelectionState().SelectNone( *mTracks, GetMixerBoard() );
 #ifdef EXPERIMENTAL_SPECTRAL_EDITING
       StartFreqSelection (event.m_y, rect.y, rect.height, pTrack);
 #endif
       StartSelection(event.m_x, rect.x);
-      SelectTrack(pTrack, true);
+      GetSelectionState().SelectTrack
+         ( *mTracks, *pTrack, true, true, GetMixerBoard() );
       SetFocusedTrack(pTrack);
       //On-Demand: check to see if there is an OD thing associated with this track.
       if (pTrack->GetKind() == Track::Wave) {
@@ -2941,8 +2796,9 @@ void TrackPanel::SelectionHandleDrag(wxMouseEvent & event, Track *clickedTrack)
    // Handle which tracks are selected
    Track *sTrack = pTrack;
    Track *eTrack = FindCell(x, y).pTrack;
-   if( !event.ControlDown() )
+   if( !event.ControlDown() && sTrack && eTrack )
-      SelectRangeOfTracks(sTrack, eTrack);
+      GetSelectionState().SelectRangeOfTracks
+         ( *mTracks, *sTrack, *eTrack, GetMixerBoard() );
 
 #ifdef USE_MIDI
    if (mStretchState.mStretching) {
@@ -5141,8 +4997,7 @@ void TrackPanel::OnTrackListUpdated(wxCommandEvent & e)
          ReleaseMouse();
    }
 
-   if (mLastPickedTrack && !mTracks->Contains(mLastPickedTrack))
+   GetSelectionState().TrackListUpdated( *mTracks );
-      mLastPickedTrack = nullptr;
 
    if (e.GetClientData()) {
       OnTrackListResized(e);
@@ -5404,28 +5259,13 @@ void TrackPanel::HandleLabelClick(wxMouseEvent & event)
 void TrackPanel::HandleListSelection(Track *t, bool shift, bool ctrl,
                                      bool modifyState)
 {
-   // AS: If the shift button is being held down, invert
+   GetSelectionState().HandleListSelection
-   //  the selection on this track.
+      ( *mTracks, *mViewInfo, *t, shift, ctrl, GetProject()->IsSyncLocked(),
-   if (ctrl) {
+        GetMixerBoard() );
-      SelectTrack(t, !t->GetSelected(), true);
-      Refresh(false);
-   }
-   else {
-      if (shift && mLastPickedTrack)
-         ChangeSelectionOnShiftClick( t );
-      else{
-         SelectNone();
-         SelectTrack(t, true);
-         SelectTrackLength(t);
-      }
 
+   if (! ctrl )
       SetFocusedTrack(t);
-      this->Refresh(false);
+   Refresh(false);
-      MixerBoard* pMixerBoard = this->GetMixerBoard();
-      if (pMixerBoard)
-         pMixerBoard->RefreshTrackClusters();
-   }
-
    if (modifyState)
       MakeParentModifyState(true);
 }
@@ -6690,7 +6530,8 @@ bool TrackPanel::HandleLabelTrackClick(LabelTrack * lTrack, const wxRect &rect,
    if (lTrack->IsSelected()) {
       SelectTracksByLabel(lTrack);
       // Do this after, for the effect on mLastPickedTrack:
-      SelectTrack(lTrack, true);
+      GetSelectionState().SelectTrack
+         ( *mTracks, *lTrack, true, true, GetMixerBoard() );
       DisplaySelection();
 
       // Not starting a drag
@@ -6822,7 +6663,7 @@ void TrackPanel::HandleTrackSpecificMouseEvent(wxMouseEvent & event)
    // AS: If the user clicked outside all tracks, make nothing
    //  selected.
    if ((event.ButtonDown() || event.ButtonDClick()) && !pTrack) {
-      SelectNone();
+      GetSelectionState().SelectNone( *mTracks, GetMixerBoard() );
       Refresh(false);
       return;
    }
@@ -7686,7 +7527,8 @@ void TrackPanel::OnPrevTrack( bool shift )
          pSelected = p->GetSelected();
       if( tSelected && pSelected )
       {
-         SelectTrack(t, false, false);
+         GetSelectionState().SelectTrack
+            ( *mTracks, *t, false, false, GetMixerBoard() );
          SetFocusedTrack( p );   // move focus to next track down
          EnsureVisible( p );
          MakeParentModifyState(false);
@@ -7694,7 +7536,8 @@ void TrackPanel::OnPrevTrack( bool shift )
       }
       if( tSelected && !pSelected )
       {
-         SelectTrack(p, true, false);
+         GetSelectionState().SelectTrack
+            ( *mTracks, *p, true, false, GetMixerBoard() );
          SetFocusedTrack( p );   // move focus to next track down
          EnsureVisible( p );
          MakeParentModifyState(false);
@@ -7702,7 +7545,8 @@ void TrackPanel::OnPrevTrack( bool shift )
       }
       if( !tSelected && pSelected )
       {
-         SelectTrack(p, false, false);
+         GetSelectionState().SelectTrack
+            ( *mTracks, *p, false, false, GetMixerBoard() );
          SetFocusedTrack( p );   // move focus to next track down
          EnsureVisible( p );
          MakeParentModifyState(false);
@@ -7710,7 +7554,8 @@ void TrackPanel::OnPrevTrack( bool shift )
       }
       if( !tSelected && !pSelected )
       {
-         SelectTrack(t, true, false);
+         GetSelectionState().SelectTrack
+            ( *mTracks, *t, true, false, GetMixerBoard() );
          SetFocusedTrack( p );   // move focus to next track down
          EnsureVisible( p );
          MakeParentModifyState(false);
@@ -7792,7 +7637,8 @@ void TrackPanel::OnNextTrack( bool shift )
       nSelected = n->GetSelected();
       if( tSelected && nSelected )
       {
-         SelectTrack(t, false, false);
+         GetSelectionState().SelectTrack
+            ( *mTracks, *t, false, false, GetMixerBoard() );
          SetFocusedTrack( n );   // move focus to next track down
          EnsureVisible( n );
          MakeParentModifyState(false);
@@ -7800,7 +7646,8 @@ void TrackPanel::OnNextTrack( bool shift )
       }
       if( tSelected && !nSelected )
       {
-         SelectTrack(n, true, false);
+         GetSelectionState().SelectTrack
+            ( *mTracks, *n, true, false, GetMixerBoard() );
          SetFocusedTrack( n );   // move focus to next track down
          EnsureVisible( n );
          MakeParentModifyState(false);
@@ -7808,7 +7655,8 @@ void TrackPanel::OnNextTrack( bool shift )
       }
       if( !tSelected && nSelected )
       {
-         SelectTrack(n, false, false);
+         GetSelectionState().SelectTrack
+            ( *mTracks, *n, false, false, GetMixerBoard() );
          SetFocusedTrack( n );   // move focus to next track down
          EnsureVisible( n );
          MakeParentModifyState(false);
@@ -7816,7 +7664,8 @@ void TrackPanel::OnNextTrack( bool shift )
       }
       if( !tSelected && !nSelected )
       {
-         SelectTrack(t, true, false);
+         GetSelectionState().SelectTrack
+            ( *mTracks, *t, true, false, GetMixerBoard() );
          SetFocusedTrack( n );   // move focus to next track down
          EnsureVisible( n );
          MakeParentModifyState(false);
@@ -7894,7 +7743,8 @@ void TrackPanel::OnToggle()
    if (!t)
       return;
 
-   SelectTrack( t, !t->GetSelected() );
+   GetSelectionState().SelectTrack
+      ( *mTracks, *t, !t->GetSelected(), true, GetMixerBoard() );
    EnsureVisible( t );
    MakeParentModifyState(false);
 

src/TrackPanel.h

@@ -25,6 +25,8 @@
 #include "Track.h"
 #include "widgets/OverlayPanel.h"
 
+#include "SelectionState.h"
+
 class wxMenu;
 class wxRect;
 
@@ -216,8 +218,6 @@ class AUDACITY_DLL_API TrackPanel final : public OverlayPanel {
    // Either argument may be NULL
    virtual void GetTracksUsableArea(int *width, int *height) const;
 
-   virtual void SelectNone();
-
    virtual void Refresh(bool eraseBackground = true,
                         const wxRect *rect = (const wxRect *) NULL);
    virtual void RefreshTrack(Track *trk, bool refreshbacking = true);
@@ -343,8 +343,6 @@ class AUDACITY_DLL_API TrackPanel final : public OverlayPanel {
 #endif
 
    // AS: Selection handling
-   void SelectTrack(Track *track, bool selected, bool updateLastPicked = true);
-   void SelectRangeOfTracks(Track *sTrack, Track *eTrack);
    size_t GetTrackCount();
    size_t GetSelectedTrackCount();
    virtual void HandleSelect(wxMouseEvent & event);
@@ -352,7 +350,6 @@ class AUDACITY_DLL_API TrackPanel final : public OverlayPanel {
 
 protected:
 
-   virtual void ChangeSelectionOnShiftClick(Track * pTrack);
    virtual void SelectionHandleClick(wxMouseEvent &event,
                                      Track* pTrack, wxRect rect);
    virtual void StartSelection (int mouseXCoordinate, int trackLeftEdge);
@@ -381,7 +378,6 @@ protected:
 #endif
 
    virtual void SelectTracksByLabel( LabelTrack *t );
-   virtual void SelectTrackLength(Track *t);
 
    // AS: Cursor handling
    virtual bool SetCursorByActivity( );
@@ -644,13 +640,13 @@ protected:
 
    SelectedRegion mInitialSelection;
    std::vector<bool> mInitialTrackSelection;
+   SelectionState mSelectionState{};
+   SelectionState &GetSelectionState() { return mSelectionState; }
    Track *mInitialLastPickedTrack {};
 
    bool mSelStartValid;
    double mSelStart;
 
-   Track *mLastPickedTrack {};
-
 #ifdef EXPERIMENTAL_SPECTRAL_EDITING
    enum eFreqSelMode {
       FREQ_SEL_INVALID,

win/Projects/Audacity/Audacity.vcxproj

@@ -197,6 +197,7 @@
     <ClCompile Include="..\..\..\src\SampleFormat.cpp" />
     <ClCompile Include="..\..\..\src\Screenshot.cpp" />
     <ClCompile Include="..\..\..\src\SelectedRegion.cpp" />
+    <ClCompile Include="..\..\..\src\SelectionState.cpp" />
     <ClCompile Include="..\..\..\src\Sequence.cpp" />
     <ClCompile Include="..\..\..\src\Shuttle.cpp" />
     <ClCompile Include="..\..\..\src\ShuttleGui.cpp" />
@@ -457,6 +458,7 @@
     <ClInclude Include="..\..\..\src\RealFFTf48x.h" />
     <ClInclude Include="..\..\..\src\RevisionIdent.h" />
     <ClInclude Include="..\..\..\src\SelectedRegion.h" />
+    <ClInclude Include="..\..\..\src\SelectionState.h" />
     <ClInclude Include="..\..\..\src\SseMathFuncs.h" />
     <ClInclude Include="..\..\..\src\toolbars\ScrubbingToolBar.h" />
     <ClInclude Include="..\..\..\src\toolbars\SpectralSelectionBar.h" />

win/Projects/Audacity/Audacity.vcxproj.filters

@@ -905,6 +905,9 @@
     <ClCompile Include="..\..\..\src\blockfile\NotYetAvailableException.cpp">
       <Filter>src\blockfile</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\..\src\SelectionState.cpp">
+      <Filter>src</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\..\..\src\AboutDialog.h">
@@ -1834,6 +1837,9 @@
     <ClInclude Include="..\..\..\src\blockfile\NotYetAvailableException.h">
       <Filter>src\blockfile</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\..\src\SelectionState.h">
+      <Filter>src</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <Image Include="..\..\audacity.ico">