Decoupling the FWidget and FWindow classes from FVTerm

ChangeLog

@@ -1,3 +1,8 @@
+2021-04-18 Markus Gans  <guru.mail@muenster.de>
+	* Decoupling the FWidget and FWindow classes from FVTerm
+	* Avoid redrawing widgets when show() is called multiple times
+	* Readjustment of the root widget when the terminal size is changed
+
 2021-04-11 Markus Gans  <guru.mail@muenster.de>
 	* Better support for kitty terminals
 

src/fdialog.cpp

@@ -766,8 +766,11 @@ void FDialog::onWindowLowered (FEvent*)
   if ( getWindowList()->empty() )
     return;
 
-  for (auto&& win : *getWindowList())
+  for (auto&& window : *getWindowList())
+  {
+    const auto win = static_cast<FWidget*>(window);
     putArea (win->getTermPos(), win->getVWin());
+  }
 }
 
 
@@ -1216,8 +1219,10 @@ void FDialog::restoreOverlaidWindows()
 
   bool overlaid{false};
 
-  for (auto&& win : *getWindowList())
+  for (auto&& window : *getWindowList())
   {
+    const auto win = static_cast<FWidget*>(window);
+
     if ( overlaid )
       putArea (win->getTermPos(), win->getVWin());
 

src/flistbox.cpp

@@ -599,18 +599,15 @@ void FListBox::adjustSize()
   hbar->setWidth (width, false);
   hbar->resize();
 
-  if ( isShown() )
+  if ( isHorizontallyScrollable() )
-  {
+    hbar->show();
-    if ( isHorizontallyScrollable() )
+  else
-      hbar->show();
+    hbar->hide();
-    else
-      hbar->hide();
 
-    if ( isVerticallyScrollable() )
+  if ( isVerticallyScrollable() )
-      vbar->show();
+    vbar->show();
-    else
+  else
-      vbar->hide();
+    vbar->hide();
-  }
 }
 
 

src/flistview.cpp

@@ -1368,18 +1368,15 @@ void FListView::adjustScrollbars (const std::size_t element_count) const
   hbar->setWidth (width, false);
   hbar->resize();
 
-  if ( isShown() )
+  if ( isHorizontallyScrollable() )
-  {
+    hbar->show();
-    if ( isHorizontallyScrollable() )
+  else
-      hbar->show();
+    hbar->hide();
-    else
-      hbar->hide();
 
-    if ( isVerticallyScrollable() )
+  if ( isVerticallyScrollable() )
-      vbar->show();
+    vbar->show();
-    else
+  else
-      vbar->hide();
+    vbar->hide();
-  }
 }
 
 //----------------------------------------------------------------------

src/fscrollview.cpp

@@ -638,11 +638,8 @@ void FScrollView::adjustSize()
   vbar->setValue (yoffset);
   vbar->resize();
 
-  if ( isShown() )
+  setHorizontalScrollBarVisibility();
-  {
+  setVerticalScrollBarVisibility();
-    setHorizontalScrollBarVisibility();
-    setVerticalScrollBarVisibility();
-  }
 }
 
 //----------------------------------------------------------------------

src/ftermdetection.cpp

@@ -457,28 +457,14 @@ bool FTermDetection::get256colorEnvString()
   color_env.string7 = std::getenv("COLORFGBG");
   color_env.string7 = std::getenv("KITTY_WINDOW_ID");
 
-  if ( color_env.string1 != nullptr )
+  if ( color_env.string1 != nullptr
-    return true;
+    || color_env.string2 != nullptr
-
+    || color_env.string3 != nullptr
-  if ( color_env.string2 != nullptr )
+    || color_env.string4 != nullptr
-    return true;
+    || color_env.string5 != nullptr
-
+    || color_env.string6 != nullptr
-  if ( color_env.string3 != nullptr )
+    || color_env.string7 != nullptr
-    return true;
+    || color_env.string8 != nullptr )
-
-  if ( color_env.string4 != nullptr )
-    return true;
-
-  if ( color_env.string5 != nullptr )
-    return true;
-
-  if ( color_env.string6 != nullptr )
-    return true;
-
-  if ( color_env.string7 != nullptr )
-    return true;
-
-  if ( color_env.string8 != nullptr )
     return true;
 
   return false;

src/ftextview.cpp

@@ -526,18 +526,15 @@ void FTextView::adjustSize()
   hbar->setValue (xoffset);
   hbar->resize();
 
-  if ( isShown() )
+  if ( isHorizontallyScrollable() )
-  {
+    hbar->show();
-    if ( isHorizontallyScrollable() )
+  else
-      hbar->show();
+    hbar->hide();
-    else
-      hbar->hide();
 
-    if ( isVerticallyScrollable() )
+  if ( isVerticallyScrollable() )
-      vbar->show();
+    vbar->show();
-    else
+  else
-      vbar->hide();
+    vbar->hide();
-  }
 }
 
 

src/fvterm.cpp

@@ -48,8 +48,6 @@
 #include "final/ftermcap.h"
 #include "final/ftypes.h"
 #include "final/fvterm.h"
-#include "final/fwidget.h"
-#include "final/fwindow.h"
 
 namespace finalcut
 {
@@ -96,6 +94,7 @@ FVTerm::FVTerm()
     fterm = std::shared_ptr<FTerm>(init_object->fterm);
     term_pos = std::shared_ptr<FPoint>(init_object->term_pos);
     output_buffer = std::shared_ptr<OutputBuffer>(init_object->output_buffer);
+    window_list = std::shared_ptr<FVTermList>(init_object->window_list);
   }
 }
 
@@ -651,7 +650,7 @@ void FVTerm::createArea ( const FRect& box
     return;
   }
 
-  area->widget = reinterpret_cast<FWidget*>(this);
+  area->setOwner<FVTerm*>(this);
   resizeArea (box, shadow, area);
 }
 
@@ -1082,6 +1081,28 @@ void FVTerm::putArea (const FPoint& pos, const FTermArea* area)
   vterm->has_changes = true;
 }
 
+//----------------------------------------------------------------------
+int FVTerm::getLayer (FVTerm* obj)
+{
+  // returns the layer from the FVTerm object
+
+  if ( ! getWindowList() || getWindowList()->empty() )
+    return -1;
+
+  auto iter = getWindowList()->begin();
+  const auto end = getWindowList()->end();
+
+  while ( iter != end )
+  {
+    if ( *iter == obj )
+      break;
+
+    ++iter;
+  }
+
+  return int(std::distance(getWindowList()->begin(), iter) + 1);
+}
+
 //----------------------------------------------------------------------
 void FVTerm::scrollAreaForward (FTermArea* area) const
 {
@@ -1389,11 +1410,11 @@ FVTerm::CoveredState FVTerm::isCovered ( const FPoint& pos
 
   auto is_covered = CoveredState::None;
 
-  if ( FWidget::getWindowList() && ! FWidget::getWindowList()->empty() )
+  if ( getWindowList() && ! getWindowList()->empty() )
   {
     bool found{ area == vdesktop };
 
-    for (auto& win_obj : *FWidget::getWindowList())
+    for (auto& win_obj : *getWindowList())
     {
       const auto& win = win_obj->getVWin();
 
@@ -1590,13 +1611,10 @@ void FVTerm::updateVTerm() const
     vdesktop->has_changes = false;
   }
 
-  const FWidget* widget = vterm->widget;
+  if ( ! getWindowList() || getWindowList()->empty() )
-
-  if ( ! widget || ! widget->getWindowList()
-    || widget->getWindowList()->empty() )
     return;
 
-  for (auto&& window : *(widget->getWindowList()))
+  for (auto&& window : *getWindowList())
   {
     auto v_win = window->getVWin();
 
@@ -1686,10 +1704,10 @@ FChar FVTerm::generateCharacter (const FPoint& pos)
   const int y = pos.getY();
   auto sc = &vdesktop->data[y * vdesktop->width + x];  // shown character
 
-  if ( ! FWidget::getWindowList() || FWidget::getWindowList()->empty() )
+  if ( ! getWindowList() || getWindowList()->empty() )
     return *sc;
 
-  for (auto& win_obj : *FWidget::getWindowList())
+  for (auto& win_obj : *getWindowList())
   {
     const auto& win = win_obj->getVWin();
 
@@ -1767,24 +1785,26 @@ FChar FVTerm::getCharacter ( CharacterType char_type
 
   auto cc = &vdesktop->data[yy * vdesktop->width + xx];  // covered character
 
-  if ( ! area || ! FWidget::getWindowList() || FWidget::getWindowList()->empty() )
+  if ( ! area || ! getWindowList() || getWindowList()->empty() )
     return *cc;
 
   // Get the window layer of this widget object
-  const int layer = FWindow::getWindowLayer(area->widget);
+  const auto has_an_owner = area->hasOwner();
+  const auto area_owner = area->getOwner<FVTerm*>();
+  const int layer = has_an_owner ? getLayer(area_owner) : 0;
 
-  for (auto&& win_obj : *FWidget::getWindowList())
+  for (auto&& win_obj : *getWindowList())
   {
     bool significant_char{false};
 
     // char_type can be "overlapped_character"
     // or "covered_character"
     if ( char_type == CharacterType::Covered )
-      significant_char = bool(layer >= FWindow::getWindowLayer(win_obj));
+      significant_char = bool(layer >= getLayer(win_obj));
     else
-      significant_char = bool(layer < FWindow::getWindowLayer(win_obj));
+      significant_char = bool(layer < getLayer(win_obj));
 
-    if ( area->widget && area->widget != win_obj && significant_char )
+    if ( has_an_owner && area_owner != win_obj && significant_char )
     {
       const auto& win = win_obj->getVWin();
 
@@ -1832,6 +1852,7 @@ void FVTerm::init()
     fterm         = std::make_shared<FTerm>();
     term_pos      = std::make_shared<FPoint>(-1, -1);
     output_buffer = std::make_shared<OutputBuffer>();
+    window_list   = std::make_shared<FVTermList>();
   }
   catch (const std::bad_alloc&)
   {

src/fwidget.cpp

@@ -54,7 +54,6 @@ FStatusBar*           FWidget::statusbar{nullptr};
 FMenuBar*             FWidget::menubar{nullptr};
 FWidget*              FWidget::show_root_widget{nullptr};
 FWidget*              FWidget::redraw_root_widget{nullptr};
-FWidget::FWidgetList* FWidget::window_list{nullptr};
 FWidget::FWidgetList* FWidget::dialog_list{nullptr};
 FWidget::FWidgetList* FWidget::always_on_top_list{nullptr};
 FWidget::FWidgetList* FWidget::close_widget{nullptr};
@@ -665,15 +664,16 @@ bool FWidget::setCursorPos (const FPoint& pos)
 
   const auto& area = getPrintArea();
 
-  if ( area->widget )
+  if ( area->hasOwner() )
   {
-    int woffsetX = getTermX() - area->widget->getTermX();
+    const auto object = area->getOwner<FWidget*>();
-    int woffsetY = getTermY() - area->widget->getTermY();
+    int woffsetX = getTermX() - object->getTermX();
+    int woffsetY = getTermY() - object->getTermY();
 
     if ( isChildPrintArea() )
     {
-      woffsetX += (1 - area->widget->getLeftPadding());
+      woffsetX += (1 - object->getLeftPadding());
-      woffsetY += (1 - area->widget->getTopPadding());
+      woffsetY += (1 - object->getTopPadding());
     }
 
     bool visible = ! isCursorHideable() || flags.visible_cursor;
@@ -959,7 +959,7 @@ void FWidget::show()
 {
   // Make the widget visible and draw it
 
-  if ( ! isVisible() || FApplication::isQuit() )
+  if ( ! isVisible() || isShown() || FApplication::isQuit() )
     return;
 
   // Initialize desktop on first call
@@ -1352,10 +1352,12 @@ void FWidget::adjustSizeGlobal()
     return;
   }
 
-  if ( window_list && ! window_list->empty() )
+  adjustSize();  // Root widget / FApplication object
+
+  if ( getWindowList() && ! getWindowList()->empty() )
   {
-    for (auto&& window : *window_list)
+    for (auto&& window : *getWindowList())
-      window->adjustSize();
+      static_cast<FWidget*>(window)->adjustSize();
   }
 }
 
@@ -1749,7 +1751,6 @@ void FWidget::initRootWidget()
   try
   {
     // Initialize widget lists
-    window_list        = new FWidgetList();
     dialog_list        = new FWidgetList();
     always_on_top_list = new FWidgetList();
     close_widget       = new FWidgetList();
@@ -1813,12 +1814,6 @@ void FWidget::finish()
     delete always_on_top_list;
     always_on_top_list = nullptr;
   }
-
-  if ( window_list )
-  {
-    delete window_list;
-    window_list = nullptr;
-  }
 }
 
 //----------------------------------------------------------------------
@@ -1946,7 +1941,7 @@ void FWidget::setWindowFocus (bool enable)
   if ( ! window->isWindowActive() )
   {
     bool has_raised = window->raiseWindow();
-    FWindow::setActiveWindow(window);
+    window->setActiveWindow(window);
 
     if ( has_raised && window->isVisible() && window->isShown() )
       window->redraw();
@@ -2012,18 +2007,20 @@ void FWidget::drawWindows() const
   default_char.attr.byte[0] = 0;
   default_char.attr.byte[1] = 0;
 
-  if ( ! window_list || window_list->empty() )
+  if ( ! getWindowList() || getWindowList()->empty() )
     return;
 
-  for (auto&& window : *window_list)
+  for (auto&& window : *getWindowList())
   {
-    if ( window->isShown() )
+    const auto win = static_cast<FWidget*>(window);
+
+    if ( win->isShown() )
     {
-      auto v_win = window->getVWin();
+      auto v_win = win->getVWin();
       const int w = v_win->width  + v_win->right_shadow;
       const int h = v_win->height + v_win->bottom_shadow;
       std::fill_n (v_win->data, w * h, default_char);
-      window->redraw();
+      win->redraw();
     }
   }
 }

src/fwindow.cpp

@@ -3,7 +3,7 @@
 *                                                                      *
 * This file is part of the FINAL CUT widget toolkit                    *
 *                                                                      *
-* Copyright 2015-2020 Markus Gans                                      *
+* Copyright 2015-2021 Markus Gans                                      *
 *                                                                      *
 * FINAL CUT is free software; you can redistribute it and/or modify    *
 * it under the terms of the GNU Lesser General Public License as       *
@@ -129,7 +129,7 @@ void FWindow::setActiveWindow (FWindow* window)
       {
         w->deactivateWindow();
         FEvent ev(Event::WindowInactive);
-        FApplication::sendEvent(win, &ev);
+        FApplication::sendEvent(static_cast<FWidget*>(win), &ev);
       }
     }
   }
@@ -365,12 +365,10 @@ void FWindow::setHeight (std::size_t h, bool adjust)
 //----------------------------------------------------------------------
 void FWindow::setSize (const FSize& size, bool adjust)
 {
-  const std::size_t old_width = getWidth();
+  const FSize old_size{getSize()};
-  const std::size_t old_height = getHeight();
   FWidget::setSize (size, adjust);
 
-  if ( isVirtualWindow()
+  if ( isVirtualWindow() && getSize() != old_size )
-    && (getWidth() != old_width || getHeight() != old_height) )
   {
     FRect geometry {getTermGeometry()};
     geometry.move(-1, -1);
@@ -429,6 +427,7 @@ void FWindow::move (const FPoint& pos)
 FWindow* FWindow::getWindowWidgetAt (int x, int y)
 {
   // returns the window object to the corresponding coordinates
+
   if ( getWindowList() && ! getWindowList()->empty() )
   {
     auto iter = getWindowList()->end();
@@ -482,56 +481,6 @@ void FWindow::delWindow (const FWidget* obj)
   }
 }
 
-//----------------------------------------------------------------------
-FWindow* FWindow::getWindowWidget (FWidget* obj)
-{
-  // returns the window object to the given widget obj
-  auto p_obj = obj->getParentWidget();
-
-  while ( ! obj->isWindowWidget() && p_obj )
-  {
-    obj = p_obj;
-    p_obj = p_obj->getParentWidget();
-  }
-
-  if ( obj->isWindowWidget() )
-    return static_cast<FWindow*>(obj);
-  else
-    return nullptr;
-}
-
-//----------------------------------------------------------------------
-int FWindow::getWindowLayer (FWidget* obj)
-{
-  // returns the window layer from the widget obj
-
-  const FWidget* window;
-
-  if ( ! getWindowList() || getWindowList()->empty() )
-    return -1;
-
-  if ( ! obj->isWindowWidget() )
-  {
-    if ( (window = getWindowWidget(obj)) == nullptr )
-      return -1;
-  }
-  else
-    window = obj;
-
-  auto iter = getWindowList()->begin();
-  const auto end  = getWindowList()->end();
-
-  while ( iter != end )
-  {
-    if ( *iter == window )
-      break;
-
-    ++iter;
-  }
-
-  return int(std::distance(getWindowList()->begin(), iter) + 1);
-}
-
 //----------------------------------------------------------------------
 void FWindow::swapWindow (const FWidget* obj1, const FWidget* obj2)
 {
@@ -582,18 +531,19 @@ bool FWindow::raiseWindow (FWidget* obj)
   if ( ! obj->isWindowWidget() )
     return false;
 
-  if ( getWindowList()->back() == obj )
+  const auto last = static_cast<FWidget*>(getWindowList()->back());
+
+  if ( last == obj )
     return false;
 
-  if ( getWindowList()->back()->getFlags().modal
+  if ( last->getFlags().modal && ! obj->isMenuWidget() )
-    && ! obj->isMenuWidget() )
     return false;
 
   auto iter = getWindowList()->begin();
 
   while ( iter != getWindowList()->end() )
   {
-    if ( *iter == obj )
+    if ( static_cast<FWidget*>(*iter) == obj )
     {
       getWindowList()->erase (iter);
       getWindowList()->push_back (obj);
@@ -686,8 +636,7 @@ void FWindow::switchToPrevWindow (const FWidget* widget)
   const bool is_activated = activatePrevWindow();
   auto active_win = static_cast<FWindow*>(getActiveWindow());
 
-  if ( ! is_activated
+  if ( ! is_activated && getWindowList() && getWindowList()->size() > 1 )
-    && getWindowList() && getWindowList()->size() > 1 )
   {
     // no previous window -> looking for another window
     auto iter = getWindowList()->end();
@@ -716,7 +665,7 @@ void FWindow::switchToPrevWindow (const FWidget* widget)
     auto focus = active_win->getWindowFocusWidget();
 
     if ( ! active_win->isWindowActive() )
-      setActiveWindow(active_win);
+      active_win->setActiveWindow(active_win);
 
     if ( focus )
     {
@@ -745,7 +694,7 @@ bool FWindow::activatePrevWindow()
 
     if ( ! w->isWindowHidden() )
     {
-      setActiveWindow(w);
+      w->setActiveWindow(w);
       return true;
     }
   }
@@ -885,6 +834,42 @@ void FWindow::processAlwaysOnTop()
   }
 }
 
+//----------------------------------------------------------------------
+FWindow* FWindow::getWindowWidgetImpl (FWidget* obj)
+{
+  // returns the window object to the given widget obj
+  auto p_obj = obj->getParentWidget();
+
+  while ( ! obj->isWindowWidget() && p_obj )
+  {
+    obj = p_obj;
+    p_obj = p_obj->getParentWidget();
+  }
+
+  if ( obj->isWindowWidget() )
+    return static_cast<FWindow*>(obj);
+  else
+    return nullptr;
+}
+
+//----------------------------------------------------------------------
+int FWindow::getWindowLayerImpl (FWidget* obj)
+{
+  // returns the window layer from the widget obj
+
+  FWidget* window;
+
+  if ( ! obj->isWindowWidget() )
+  {
+    if ( (window = getWindowWidget(obj)) == nullptr )
+      return -1;
+  }
+  else
+    window = obj;
+
+  return FVTerm::getLayer(window);
+}
+
 // non-member functions
 //----------------------------------------------------------------------
 void closeDropDown (const FWidget* widget, const FPoint& mouse_position)

src/include/final/fdata.h

@@ -165,6 +165,8 @@ class FData : public FDataAccess
       , value_ref{value}
     { }
 
+    ~FData() noexcept override = default;  // Destructor
+
     FData (const FData& d)  // Copy constructor
       : value{d.value}
       , value_ref{d.isInitializedCopy() ? std::ref(value) : d.value_ref}

src/include/final/fvterm.h

@@ -58,6 +58,7 @@
 #include <vector>
 
 #include "final/fc.h"
+#include "final/fdata.h"
 #include "final/fstringstream.h"
 #include "final/fterm.h"
 
@@ -79,7 +80,7 @@ class FTerm;
 class FTermBuffer;
 class FTermDebugData;
 class FStyle;
-class FWidget;
+
 
 //----------------------------------------------------------------------
 // class FVTerm
@@ -102,6 +103,7 @@ class FVTerm
     using FPreprocessingHandler = void (FVTerm::*)();
     using FPreprocessingFunction = std::function<void()>;
     using FPreprocessing = std::vector<std::unique_ptr<FVTermPreprocessing>>;
+    using FVTermList = std::vector<FVTerm*>;
 
     // Enumerations
     enum class CoveredState
@@ -149,6 +151,7 @@ class FVTerm
     const FTermArea*      getVWin() const;
     FPoint                getPrintCursor();
     static FChar          getAttribute();
+    static FVTermList*    getWindowList();
     FTerm&                getFTerm() const;
 
     // Mutators
@@ -278,6 +281,7 @@ class FVTerm
     static void           getArea (const FRect&, const FTermArea*);
     void                  putArea (const FTermArea*) const;
     static void           putArea (const FPoint&, const FTermArea*);
+    static int            getLayer (FVTerm*);
     void                  scrollAreaForward (FTermArea*) const;
     void                  scrollAreaReverse (FTermArea*) const;
     void                  clearArea (FTermArea*, wchar_t = L' ') const;
@@ -438,16 +442,17 @@ class FVTerm
     FTermArea*                    child_print_area{nullptr};  // print area for children
     FTermArea*                    vwin{nullptr};              // virtual window
     std::shared_ptr<FTerm>        fterm{};
-    std::shared_ptr<FPoint>       term_pos{};  // terminal cursor position
+    std::shared_ptr<FPoint>       term_pos{};     // terminal cursor position
     std::shared_ptr<OutputBuffer> output_buffer{};
-    static const FVTerm*          init_object;  // Global FVTerm object
+    std::shared_ptr<FVTermList>   window_list{};  // List of all window owner
-    static FTermArea*             vterm;        // virtual terminal
+    static const FVTerm*          init_object;    // Global FVTerm object
-    static FTermArea*             vdesktop;     // virtual desktop
+    static FTermArea*             vterm;          // virtual terminal
-    static FTermArea*             active_area;  // active area
+    static FTermArea*             vdesktop;       // virtual desktop
+    static FTermArea*             active_area;    // active area
     static FChar                  term_attribute;
     static FChar                  next_attribute;
-    static FChar                  s_ch;      // shadow character
+    static FChar                  s_ch;  // shadow character
-    static FChar                  i_ch;      // inherit background character
+    static FChar                  i_ch;  // inherit background character
     static timeval                time_last_flush;
     static timeval                last_term_size_check;
     static bool                   draw_completed;
@@ -473,6 +478,9 @@ class FVTerm
 
 struct FVTerm::FTermArea  // define virtual terminal character properties
 {
+  // Using-declaration
+  using FDataAccessPtr = std::shared_ptr<FDataAccess>;
+
   // Constructor
   FTermArea() = default;
 
@@ -485,18 +493,35 @@ struct FVTerm::FTermArea  // define virtual terminal character properties
   // Disable copy assignment operator (=)
   FTermArea& operator = (const FTermArea&) = delete;
 
+  template <typename T>
+  clean_fdata_t<T>& getOwner() const
+  {
+    return static_cast<FData<clean_fdata_t<T>>&>(*owner).get();
+  }
+
+  template <typename T>
+  void setOwner (T&& obj)
+  {
+    owner.reset(makeFData(std::forward<T>(obj)));
+  }
+
+  bool hasOwner() const
+  {
+    return owner.get() != nullptr;
+  }
+
   // Data members
-  int offset_left{0};        // Distance from left terminal side
+  int offset_left{0};             // Distance from left terminal side
-  int offset_top{0};         // Distance from top of the terminal
+  int offset_top{0};              // Distance from top of the terminal
-  int width{-1};             // Window width
+  int width{-1};                  // Window width
-  int height{-1};            // Window height
+  int height{-1};                 // Window height
-  int right_shadow{0};       // Right window shadow
+  int right_shadow{0};            // Right window shadow
-  int bottom_shadow{0};      // Bottom window shadow
+  int bottom_shadow{0};           // Bottom window shadow
-  int cursor_x{0};           // X-position for the next write operation
+  int cursor_x{0};                // X-position for the next write operation
-  int cursor_y{0};           // Y-position for the next write operation
+  int cursor_y{0};                // Y-position for the next write operation
-  int input_cursor_x{-1};    // X-position input cursor
+  int input_cursor_x{-1};         // X-position input cursor
-  int input_cursor_y{-1};    // Y-position input cursor
+  int input_cursor_y{-1};         // Y-position input cursor
-  FWidget* widget{nullptr};  // Widget that owns this FTermArea
+  FDataAccessPtr owner{nullptr};  // Object that owns this FTermArea
   FPreprocessing preproc_list{};
   FLineChanges* changes{nullptr};
   FChar* data{nullptr};      // FChar data of the drawing area
@@ -617,6 +642,14 @@ inline const FVTerm::FTermArea* FVTerm::getVWin() const
 inline FChar FVTerm::getAttribute()
 { return next_attribute; }
 
+//----------------------------------------------------------------------
+inline FVTerm::FVTermList* FVTerm::getWindowList()
+{
+  return (init_object && init_object->window_list)
+        ? init_object->window_list.get()
+        : nullptr;
+}
+
 //----------------------------------------------------------------------
 inline FTerm& FVTerm::getFTerm() const
 { return *fterm; }

src/include/final/fwidget.h

@@ -183,7 +183,6 @@ class FWidget : public FVTerm, public FObject
     static FWidget*&         getClickedWidget();
     static FWidget*&         getOpenMenu();
     static FWidget*&         getMoveSizeWidget();
-    static FWidgetList*&     getWindowList();
     static FMenuBar*         getMenuBar();
     static FStatusBar*       getStatusBar();
     static auto              getColorTheme() -> std::shared_ptr<FWidgetColors>&;
@@ -480,7 +479,6 @@ class FWidget : public FVTerm, public FObject
     static FWidget*          move_size_widget;
     static FWidget*          show_root_widget;
     static FWidget*          redraw_root_widget;
-    static FWidgetList*      window_list;
     static FWidgetList*      dialog_list;
     static FWidgetList*      always_on_top_list;
     static FWidgetList*      close_widget;
@@ -555,10 +553,6 @@ inline FWidget*& FWidget::getOpenMenu()
 inline FWidget*& FWidget::getMoveSizeWidget()
 { return move_size_widget; }
 
-//----------------------------------------------------------------------
-inline FWidget::FWidgetList*& FWidget::getWindowList()
-{ return window_list; }
-
 //----------------------------------------------------------------------
 inline FMenuBar* FWidget::getMenuBar()
 { return menubar; }

src/include/final/fwindow.h

@@ -84,8 +84,10 @@ class FWindow : public FWidget
 
     // Accessors
     FString             getClassName() const override;
-    static FWindow*     getWindowWidget (FWidget*);
+    template<typename WidgetT>
-    static int          getWindowLayer (FWidget*);
+    static FWindow*     getWindowWidget (WidgetT*);
+    template<typename WidgetT>
+    static int          getWindowLayer (WidgetT*);
     FWidget*            getWindowFocusWidget() const;
 
     // Mutators
@@ -159,6 +161,8 @@ class FWindow : public FWidget
     // Methods
     static void         deleteFromAlwaysOnTopList (const FWidget*);
     static void         processAlwaysOnTop();
+    static FWindow*     getWindowWidgetImpl (FWidget*);
+    static int          getWindowLayerImpl (FWidget*);
 
     // Data members
     FWidget*            win_focus_widget{nullptr};
@@ -178,6 +182,21 @@ void closeDropDown (const FWidget*, const FPoint&);
 inline FString FWindow::getClassName() const
 { return "FWindow"; }
 
+//----------------------------------------------------------------------
+
+template<typename WidgetT>
+inline FWindow* FWindow::getWindowWidget (WidgetT* obj)
+{
+  return getWindowWidgetImpl (static_cast<FWidget*>(obj));
+}
+
+//----------------------------------------------------------------------
+template<typename WidgetT>
+inline int FWindow::getWindowLayer (WidgetT* obj)
+{
+  return getWindowLayerImpl (static_cast<FWidget*>(obj));
+}
+
 //----------------------------------------------------------------------
 inline bool FWindow::unsetWindowWidget()
 { return setWindowWidget(false); }