All UIHandle::Preview() return same cursors, messages as HitTest...

... except TrackSelectHandle.  Cursor changes to a hand only after button-down.

HitTests give a UIHandle, whenever they also give any cursor or status, even
when it's unsafe to click and drag; Click override is reponsible for cancelling.

SelectHandle::Preview introduces much duplication, but the original in the hit
test will later be deleted.

src/tracks/playabletrack/notetrack/ui/StretchHandle.cpp

@@ -155,10 +155,12 @@ UIHandle::Result StretchHandle::Click
 {
    using namespace RefreshCode;
    const bool unsafe = pProject->IsAudioActive();
+   if ( unsafe )
+      return Cancelled;
+
    const wxMouseEvent &event = evt.event;
 
-   if (unsafe ||
-       event.LeftDClick() ||
+   if (event.LeftDClick() ||
        !event.LeftDown() ||
        evt.pCell == NULL)
       return Cancelled;

src/tracks/playabletrack/wavetrack/ui/CutlineHandle.cpp

@@ -50,12 +50,7 @@ HitTestPreview CutlineHandle::HitPreview(bool cutline, bool unsafe)
 HitTestResult CutlineHandle::HitAnywhere(const AudacityProject *pProject, bool cutline)
 {
    const bool unsafe = pProject->IsAudioActive();
-   return {
-      HitPreview(cutline, unsafe),
-      (unsafe
-      ? NULL
-      : &Instance())
-   };
+   return { HitPreview(cutline, unsafe), &Instance() };
 }
 
 namespace
@@ -131,6 +126,11 @@ CutlineHandle::~CutlineHandle()
 UIHandle::Result CutlineHandle::Click
 (const TrackPanelMouseEvent &evt, AudacityProject *pProject)
 {
+   using namespace RefreshCode;
+   const bool unsafe = pProject->IsAudioActive();
+   if ( unsafe )
+      return Cancelled;
+
    const wxMouseEvent &event = evt.event;
    ViewInfo &viewInfo = pProject->GetViewInfo();
    const auto pTrack = static_cast<Track*>(evt.pCell.get());
@@ -138,12 +138,8 @@ UIHandle::Result CutlineHandle::Click
    // Can affect the track by merging clips, expanding a cutline, or
    // deleting a cutline.
    // All the change is done at button-down.  Button-up just commits the undo item.
-   using namespace RefreshCode;
 
    /// Someone has just clicked the mouse.  What do we do?
-   const bool unsafe = pProject->IsAudioActive();
-   if (unsafe)
-      return Cancelled;
 
    WaveTrackLocation capturedTrackLocation;
 
@@ -222,9 +218,10 @@ UIHandle::Result CutlineHandle::Drag
 }
 
 HitTestPreview CutlineHandle::Preview
-(const TrackPanelMouseState &, const AudacityProject *)
+(const TrackPanelMouseState &, const AudacityProject *pProject)
 {
-   return HitPreview(mbCutline, false);
+   const bool unsafe = pProject->IsAudioActive();
+   return HitPreview( mbCutline, unsafe );
 }
 
 UIHandle::Result CutlineHandle::Release

src/tracks/playabletrack/wavetrack/ui/SampleHandle.cpp

@@ -67,12 +67,7 @@ HitTestResult SampleHandle::HitAnywhere
 (const wxMouseState &state, const AudacityProject *pProject)
 {
    const bool unsafe = pProject->IsAudioActive();
-   return {
-      HitPreview(state, pProject, unsafe),
-      (unsafe
-      ? NULL
-      : &Instance())
-   };
+   return { HitPreview(state, pProject, unsafe), &Instance() };
 }
 
 namespace {
@@ -206,17 +201,17 @@ namespace {
 UIHandle::Result SampleHandle::Click
 (const TrackPanelMouseEvent &evt, AudacityProject *pProject)
 {
+   using namespace RefreshCode;
+   const bool unsafe = pProject->IsAudioActive();
+   if ( unsafe )
+      return Cancelled;
+
    const wxMouseEvent &event = evt.event;
    const wxRect &rect = evt.rect;
    const ViewInfo &viewInfo = pProject->GetViewInfo();
    const auto pTrack = std::static_pointer_cast<WaveTrack>(evt.pCell);
 
-   using namespace RefreshCode;
-
    /// Someone has just clicked the mouse.  What do we do?
-   const bool unsafe = pProject->IsAudioActive();
-   if (unsafe)
-      return Cancelled;
    if (!IsSampleEditingPossible(
          event, rect, viewInfo, pTrack.get(), rect.width))
       return Cancelled;
@@ -419,7 +414,8 @@ UIHandle::Result SampleHandle::Drag
 HitTestPreview SampleHandle::Preview
 (const TrackPanelMouseState &st, const AudacityProject *pProject)
 {
-   return HitPreview(st.state, pProject, false);
+   const bool unsafe = pProject->IsAudioActive();
+   return HitPreview(st.state, pProject, unsafe);
 }
 
 UIHandle::Result SampleHandle::Release

src/tracks/ui/EnvelopeHandle.cpp

@@ -54,12 +54,7 @@ HitTestPreview EnvelopeHandle::HitPreview(const AudacityProject *pProject, bool
 HitTestResult EnvelopeHandle::HitAnywhere(const AudacityProject *pProject)
 {
    const bool unsafe = pProject->IsAudioActive();
-   return {
-      HitPreview(pProject, unsafe),
-      (unsafe
-       ? NULL
-       : &Instance())
-   };
+   return { HitPreview(pProject, unsafe), &Instance() };
 }
 
 namespace {
@@ -182,15 +177,15 @@ EnvelopeHandle::~EnvelopeHandle()
 UIHandle::Result EnvelopeHandle::Click
 (const TrackPanelMouseEvent &evt, AudacityProject *pProject)
 {
+   using namespace RefreshCode;
+   const bool unsafe = pProject->IsAudioActive();
+   if ( unsafe )
+      return Cancelled;
+
    const wxMouseEvent &event = evt.event;
    const ViewInfo &viewInfo = pProject->GetViewInfo();
    const auto pTrack = static_cast<Track*>(evt.pCell.get());
 
-   using namespace RefreshCode;
-   const bool unsafe = pProject->IsAudioActive();
-   if (unsafe)
-      return Cancelled;
-
    if (pTrack->GetKind() == Track::Wave) {
       WaveTrack *const wt = static_cast<WaveTrack*>(pTrack);
       if (wt->GetDisplay() != WaveTrack::Waveform)
@@ -257,7 +252,8 @@ UIHandle::Result EnvelopeHandle::Drag
 HitTestPreview EnvelopeHandle::Preview
 (const TrackPanelMouseState &, const AudacityProject *pProject)
 {
-   return HitPreview(pProject, false);
+   const bool unsafe = pProject->IsAudioActive();
+   return HitPreview(pProject, unsafe);
 }
 
 UIHandle::Result EnvelopeHandle::Release

src/tracks/ui/SelectHandle.cpp

@@ -49,6 +49,11 @@ enum {
 
 // #define SPECTRAL_EDITING_ESC_KEY
 
+bool SelectHandle::IsClicked() const
+{
+   return mSelectionStateChanger.get();
+}
+
 SelectHandle::SelectHandle()
 {
 }
@@ -888,14 +893,95 @@ UIHandle::Result SelectHandle::Drag
 }
 
 HitTestPreview SelectHandle::Preview
-(const TrackPanelMouseState &, const AudacityProject *pProject)
+(const TrackPanelMouseState &st, const AudacityProject *pProject)
 {
+   auto pTrack = mpTrack.lock();
+   if (!pTrack)
+      return {};
+
    wxString tip;
-   wxCursor *pCursor;
-   SetTipAndCursorForBoundary
-      (SelectionBoundary(mSelectionBoundary),
-       (mFreqSelMode == FREQ_SEL_SNAPPING_CENTER),
-       tip, pCursor);
+   wxCursor *pCursor = SelectCursor();
+   if ( IsClicked() )
+      // Use same cursor as at the clck
+      SetTipAndCursorForBoundary
+         (SelectionBoundary(mSelectionBoundary),
+          (mFreqSelMode == FREQ_SEL_SNAPPING_CENTER),
+          tip, pCursor);
+   else {
+      // Choose one of many cursors for mouse-over
+
+      const ViewInfo &viewInfo = pProject->GetViewInfo();
+
+      const bool bMultiToolMode =
+         pProject->GetToolsToolBar()->IsDown(multiTool);
+
+      //In Multi-tool mode, give multitool prompt if no-special-hit.
+      if (bMultiToolMode) {
+         // Look up the current key binding for Preferences.
+         // (Don't assume it's the default!)
+         wxString keyStr
+            (pProject->GetCommandManager()->GetKeyFromName(wxT("Preferences")));
+         if (keyStr.IsEmpty())
+            // No keyboard preference defined for opening Preferences dialog
+            /* i18n-hint: These are the names of a menu and a command in that menu */
+            keyStr = _("Edit, Preferences...");
+         else
+            keyStr = KeyStringDisplay(keyStr);
+         /* i18n-hint: %s is usually replaced by "Ctrl+P" for Windows/Linux, "Command+," for Mac */
+         tip = wxString::Format(
+            _("Multi-Tool Mode: %s for Mouse and Keyboard Preferences."),
+            keyStr.c_str());
+         // Later in this function we may point to some other string instead.
+         if (!pTrack->GetSelected() ||
+             !viewInfo.bAdjustSelectionEdges)
+            ;
+         else {
+            const auto &state = st.state;
+            const wxRect &rect = st.rect;
+            const bool bShiftDown = state.ShiftDown();
+            const bool bCtrlDown = state.ControlDown();
+            const bool bModifierDown = bShiftDown || bCtrlDown;
+
+            // If not shift-down and not snapping center, then
+            // choose boundaries only in snapping tolerance,
+            // and may choose center.
+            SelectionBoundary boundary =
+            ChooseBoundary(viewInfo, state, pTrack.get(), rect, !bModifierDown, !bModifierDown);
+
+            SetTipAndCursorForBoundary(boundary, !bShiftDown, tip, pCursor);
+         }
+      }
+
+#if 0
+      // This is a vestige of an idea in the prototype version.
+      // Center would snap without mouse button down, click would pin the center
+      // and drag width.
+#ifdef EXPERIMENTAL_SPECTRAL_EDITING
+      if ((mFreqSelMode == FREQ_SEL_SNAPPING_CENTER) &&
+         isSpectralSelectionTrack(pTrack)) {
+         // Not shift-down, but center frequency snapping toggle is on
+         tip = _("Click and drag to set frequency bandwidth.");
+         pCursor = &*envelopeCursor;
+         return {};
+      }
+#endif
+#endif
+
+      if (!pTrack->GetSelected() || !viewInfo.bAdjustSelectionEdges)
+         ;
+      else {
+         const auto &state = st.state;
+         const wxRect &rect = st.rect;
+         const bool bShiftDown = state.ShiftDown();
+         const bool bCtrlDown = state.ControlDown();
+         const bool bModifierDown = bShiftDown || bCtrlDown;
+         SelectionBoundary boundary = ChooseBoundary(
+            viewInfo, state, pTrack.get(), rect, !bModifierDown, !bModifierDown);
+         SetTipAndCursorForBoundary(boundary, !bShiftDown, tip, pCursor);
+      }
+
+      MaySetOnDemandTip(pTrack.get(), tip);
+   }
    if (tip == "") {
       const auto ttb = pProject->GetToolsToolBar();
       if (ttb)

src/tracks/ui/SelectHandle.h

@@ -45,6 +45,8 @@ public:
 
    virtual ~SelectHandle();
 
+   bool IsClicked() const;
+
    virtual Result Click
       (const TrackPanelMouseEvent &event, AudacityProject *pProject);
 

src/tracks/ui/TimeShiftHandle.cpp

@@ -54,12 +54,7 @@ HitTestResult TimeShiftHandle::HitAnywhere(const AudacityProject *pProject)
    // After all that, it still may be unsafe to drag.
    // Even if so, make an informative cursor change from default to "banned."
    const bool unsafe = pProject->IsAudioActive();
-   return {
-      HitPreview(pProject, unsafe),
-      (unsafe
-       ? NULL
-       : &Instance())
-   };
+   return { HitPreview(pProject, unsafe), &Instance() };
 }
 
 HitTestResult TimeShiftHandle::HitTest
@@ -413,18 +408,17 @@ void TimeShiftHandle::DoSlideHorizontal
 UIHandle::Result TimeShiftHandle::Click
 (const TrackPanelMouseEvent &evt, AudacityProject *pProject)
 {
+   using namespace RefreshCode;
+   const bool unsafe = pProject->IsAudioActive();
+   if ( unsafe )
+      return Cancelled;
+
    const wxMouseEvent &event = evt.event;
    const wxRect &rect = evt.rect;
    const ViewInfo &viewInfo = pProject->GetViewInfo();
 
    const auto pTrack = std::static_pointer_cast<Track>(evt.pCell);
 
-   using namespace RefreshCode;
-
-   const bool unsafe = pProject->IsAudioActive();
-   if (unsafe)
-      return Cancelled;
-
    TrackList *const trackList = pProject->GetTracks();
 
    mClipMoveState.clear();
@@ -771,7 +765,10 @@ UIHandle::Result TimeShiftHandle::Drag
 HitTestPreview TimeShiftHandle::Preview
 (const TrackPanelMouseState &, const AudacityProject *pProject)
 {
-   return HitPreview(pProject, false);
+   // After all that, it still may be unsafe to drag.
+   // Even if so, make an informative cursor change from default to "banned."
+   const bool unsafe = pProject->IsAudioActive();
+   return HitPreview(pProject, unsafe);
 }
 
 UIHandle::Result TimeShiftHandle::Release

src/tracks/ui/TrackSelectHandle.cpp

@@ -83,6 +83,9 @@ TrackSelectHandle::~TrackSelectHandle()
 UIHandle::Result TrackSelectHandle::Click
 (const TrackPanelMouseEvent &evt, AudacityProject *pProject)
 {
+   // If unsafe to drag, still, it does harmlessly change the selected track
+   // set on button down.
+
    using namespace RefreshCode;
    Result result = RefreshNone;
 
@@ -165,19 +168,30 @@ UIHandle::Result TrackSelectHandle::Drag
 HitTestPreview TrackSelectHandle::Preview
 (const TrackPanelMouseState &, const AudacityProject *project)
 {
-   // Note that this differs from HitPreview.
+   const auto trackCount = project->GetTrackPanel()->GetTrackCount();
+   if (mpTrack) {
+      // Has been clicked
+      static auto disabledCursor =
+         ::MakeCursor(wxCURSOR_NO_ENTRY, DisabledCursorXpm, 16, 16);
+      static wxCursor rearrangeCursor{ wxCURSOR_HAND };
 
-   static auto disabledCursor =
-      ::MakeCursor(wxCURSOR_NO_ENTRY, DisabledCursorXpm, 16, 16);
-   static wxCursor rearrangeCursor{ wxCURSOR_HAND };
-
-   const bool unsafe = GetActiveProject()->IsAudioActive();
-   return {
-      Message(project->GetTrackPanel()->GetTrackCount()),
-      (unsafe
-         ? &*disabledCursor
-         : &rearrangeCursor)
-   };
+      const bool unsafe = GetActiveProject()->IsAudioActive();
+      return {
+         Message(trackCount),
+         (unsafe
+          ? &*disabledCursor
+          : &rearrangeCursor)
+      };
+   }
+   else {
+      // Only mouse-over
+      // Don't test safety, because the click to change selection is allowed
+      static wxCursor arrowCursor{ wxCURSOR_ARROW };
+      return {
+         Message(trackCount),
+         &arrowCursor
+      };
+   }
 }
 
 UIHandle::Result TrackSelectHandle::Release