Bug 1837 - Unable to set empty track name

Also AudacityCommand dialogs now only show help button if there is help.
Also Track only shows track name over it, if there is a track name.

src/TrackArtist.cpp

@@ -486,7 +486,9 @@ void TrackArtist::DrawTrack(TrackPanelDrawingContext &context,
 
       if (mbShowTrackNameInWaveform &&
           // Exclude right channel of stereo track 
-          !(!wt->GetLinked() && wt->GetLink())) {
+          !(!wt->GetLinked() && wt->GetLink()) && 
+          // Exclude empty name.
+          !wt->GetName().IsEmpty()) {
          wxBrush Brush;
          wxCoord x,y;
          wxFont labelFont(12, wxSWISS, wxNORMAL, wxNORMAL);

src/commands/AudacityCommand.cpp

@@ -274,7 +274,9 @@ AudacityCommandDialog::AudacityCommandDialog(wxWindow * parent,
    mType = type;
    wxASSERT( pCommand );
    mpCommand = pCommand;
-   mAdditionalButtons = additionalButtons |eCancelButton | eHelpButton;
+   mAdditionalButtons = additionalButtons |eCancelButton;
+   if( !pCommand->ManualPage().IsEmpty() )
+      mAdditionalButtons |= eHelpButton;
 }
 
 bool AudacityCommandDialog::Init()

src/tracks/ui/TrackControls.cpp

@@ -20,6 +20,10 @@ Paul Licameli split from TrackPanel.cpp
 #include "../../TrackPanelMouseEvent.h"
 #include "../../Track.h"
 #include <wx/textdlg.h>
+#include "../../commands/CommandType.h"
+#include "../../commands/Command.h"
+#include "../../ShuttleGui.h"
+
 
 TrackControls::TrackControls( std::shared_ptr<Track> pTrack )
    : mwTrack{ pTrack }
@@ -153,6 +157,42 @@ BEGIN_POPUP_MENU(TrackMenuTable)
       OnMoveTrack)
 END_POPUP_MENU()
 
+
+
+
+#define SET_TRACK_NAME_PLUGIN_SYMBOL XO("Set Track Name")
+
+// An example of using an AudacityCommand simply to create a dialog.
+// We can add additional functions later, if we want to make it
+// available to scripting.
+// However there is no reason to, as SetTrackStatus is already provided.
+class SetTrackNameCommand : public AudacityCommand
+{
+public:
+   // CommandDefinitionInterface overrides
+   wxString GetSymbol() override {return SET_TRACK_NAME_PLUGIN_SYMBOL;};
+   //wxString GetDescription() override {return _("Sets the track name.");};
+   //bool DefineParams( ShuttleParams & S ) override;
+   void PopulateOrExchange(ShuttleGui & S) override;
+   //bool Apply(const CommandContext & context) override;
+
+   // Provide an override, if we want the help button.
+   // wxString ManualPage() override {return wxT("");};
+public:
+   wxString mName;
+};
+
+void SetTrackNameCommand::PopulateOrExchange(ShuttleGui & S)
+{
+   S.AddSpace(0, 5);
+
+   S.StartMultiColumn(2, wxALIGN_CENTER);
+   {
+      S.TieTextBox(_("Name:"),mName);
+   }
+   S.EndMultiColumn();
+}
+
 void TrackMenuTable::OnSetName(wxCommandEvent &)
 {
    Track *const pTrack = mpData->pTrack;
@@ -160,11 +200,14 @@ void TrackMenuTable::OnSetName(wxCommandEvent &)
    {
       AudacityProject *const proj = ::GetActiveProject();
       const wxString oldName = pTrack->GetName();
-      const wxString newName =
+
-         wxGetTextFromUser(_("Change track name to:"),
+      SetTrackNameCommand Command;
-         _("Track Name"), oldName);
+      Command.mName = oldName;
-      if (newName != wxT("")) // wxGetTextFromUser returns empty string on Cancel.
+      // Bug 1837 : We need an OK/Cancel result if we are to enter a blank string.
+      bool bResult = Command.PromptUser( proj );
+      if (bResult) 
       {
+         wxString newName = Command.mName;
          pTrack->SetName(newName);
          // if we have a linked channel this name should change as well
          // (otherwise sort by name and time will crash).