some safenew, override, remove an unused function, better comment

src/widgets/Grid.cpp

@@ -81,16 +81,6 @@ void TimeEditor::BeginEdit(int row, int col, wxGrid *grid)
    GetTimeCtrl()->SetFocus();
 }
 
-bool TimeEditor::EndEdit(int row, int col, wxGrid *grid)
-{
-    wxString newvalue;
-    bool changed = EndEdit(row, col, grid, mOldString, &newvalue);
-    if (changed) {
-        ApplyEdit(row, col, grid);
-    }
-    return changed;
-}
-
 bool TimeEditor::EndEdit(int WXUNUSED(row), int WXUNUSED(col), const wxGrid *WXUNUSED(grid), const wxString &WXUNUSED(oldval), wxString *newval)
 {
    double newtime = GetTimeCtrl()->GetValue();
@@ -156,6 +146,10 @@ void TimeEditor::SetRate(double rate)
    mRate = rate;
 }
 
+TimeRenderer::~TimeRenderer()
+{
+}
+
 void TimeRenderer::Draw(wxGrid &grid,
                         wxGridCellAttr &attr,
                         wxDC &dc,
@@ -392,13 +386,15 @@ Grid::Grid(wxWindow *parent,
    GetGridWindow()->SetAccessible(mAx = safenew GridAx(this));
 #endif
 
+   // RegisterDataType takes ownership of renderer and editor
+
    RegisterDataType(GRID_VALUE_TIME,
-                    new TimeRenderer,
-                    new TimeEditor);
+                    safenew TimeRenderer,
+                    safenew TimeEditor);
 
    RegisterDataType(GRID_VALUE_CHOICE,
-                    new wxGridCellStringRenderer,
-                    new ChoiceEditor);
+                    safenew wxGridCellStringRenderer,
+                    safenew ChoiceEditor);
 }
 
 Grid::~Grid()

src/widgets/Grid.h

@@ -46,21 +46,19 @@ class TimeEditor final : public wxGridCellEditor
    ~TimeEditor();
 
    // Precondition: parent != NULL
-   void Create(wxWindow *parent, wxWindowID id, wxEvtHandler *handler);
+   void Create(wxWindow *parent, wxWindowID id, wxEvtHandler *handler) override;
 
-   bool IsAcceptedKey(wxKeyEvent &event);
+   bool IsAcceptedKey(wxKeyEvent &event) override;
 
-   void SetSize(const wxRect &rect);
+   void SetSize(const wxRect &rect) override;
 
-   void BeginEdit(int row, int col, wxGrid *grid);
+   void BeginEdit(int row, int col, wxGrid *grid) override;
 
-   bool EndEdit(int row, int col, wxGrid *grid);
+   bool EndEdit(int row, int col, const wxGrid *grid, const wxString &oldval, wxString *newval) override;
 
-   bool EndEdit(int row, int col, const wxGrid *grid, const wxString &oldval, wxString *newval);
+   void ApplyEdit(int row, int col, wxGrid *grid) override;
 
-   void ApplyEdit(int row, int col, wxGrid *grid);
-
-   void Reset();
+   void Reset() override;
 
    wxString GetFormat();
    double GetRate();
@@ -68,7 +66,7 @@ class TimeEditor final : public wxGridCellEditor
    void SetRate(double rate);
 
    wxGridCellEditor *Clone() const override;
-   wxString GetValue() const;
+   wxString GetValue() const override;
 
    NumericTextCtrl *GetTimeCtrl() const { return (NumericTextCtrl *)m_control; }
 
@@ -89,20 +87,22 @@ class TimeEditor final : public wxGridCellEditor
 
 class TimeRenderer final : public wxGridCellRenderer
 {
- public:
+public:
+   ~TimeRenderer() override;
+
    void Draw(wxGrid &grid,
              wxGridCellAttr &attr,
              wxDC &dc,
              const wxRect &rect,
              int row,
              int col,
-              bool isSelected);
+             bool isSelected) override;
 
    wxSize GetBestSize(wxGrid &grid,
                       wxGridCellAttr &attr,
                       wxDC &dc,
                       int row,
-                      int col);
+                      int col) override;
 
    wxGridCellRenderer *Clone() const override;
 };

src/widgets/NumericTextCtrl.h

@@ -160,7 +160,7 @@ class NumericTextCtrl final : public wxControl, public NumericConverter
    void SetReadOnly(bool readOnly = true);
    void EnableMenu(bool enable = true);
 
-   // The text control permits typing '-' to make the value invalid only if this
+   // The text control permits typing DELETE to make the value invalid only if this
    // function has previously been called.
    // Maybe you want something other than the default of -1 to indicate the invalid value
    // this control returns to the program, so you can specify.