apps/graphics/twm4nx: Icons can now be moved, but there are artifacts: Need to erase the old icon region on the background before drawing the new icon image during the move.

graphics/twm4nx/src/cbackground.cxx

@@ -178,7 +178,7 @@ bool CBackground::checkCollision(FAR const struct nxgl_rect_s &bounds,
 {
   // Is there a background image
 
-  if (m_backImage  != (NXWidgets::CImage *)0)
+  if (m_backImage != (NXWidgets::CImage *)0)
     {
       // Create a bounding box for the background image
 
@@ -510,6 +510,14 @@ void CBackground::cleanup(void)
       m_eventq = (mqd_t)-1;
     }
 
+  // Delete the background image
+
+  if (m_backImage != (NXWidgets::CImage *)0)
+    {
+      delete m_backImage;
+      m_backImage = (NXWidgets::CImage *)0;
+    }
+
   // Delete the background
 
   if (m_backWindow != (NXWidgets::CBgWindow *)0)
@@ -528,12 +536,4 @@ void CBackground::cleanup(void)
       delete m_backWindow;
       m_backWindow = (NXWidgets::CBgWindow *)0;
     }
-
-  // Delete the background image
-
-  if (m_backImage != (NXWidgets::CImage *)0)
-    {
-      delete m_backImage;
-      m_backImage = (NXWidgets::CImage *)0;
-    }
 }

graphics/twm4nx/src/ciconwidget.cxx

@@ -102,13 +102,16 @@ CIconWidget::CIconWidget(FAR CTwm4Nx *twm4nx,
 
   // Dragging
 
-  m_drag             = false;            // No drag in-progress */
+  m_dragging         = false;            // No drag in-progress */
   m_moved            = false;            // Icon has not been moved */
 
   // Configure the widget
 
-  m_flags.borderless = true;             // The widget is borderless (and transparent)
+  setBorderless(true);                   // The widget is borderless (and transparent)
-  m_flags.draggable  = true;             // This widget may be dragged
+  setDraggable(true);                    // This widget may be dragged
+  enable();                              // Enable the widget
+  setRaisesEvents(true);                 // Enable event firing
+  disableDrawing();                      // No drawing yet
 }
 
 /**
@@ -268,13 +271,13 @@ bool CIconWidget::initialize(FAR CWindow *parent,
       iconImagePos.x = (maxLabelWidth - iconImageSize.w) / 2;
     }
 
-  // Create a new CImage to hold the bitmap image
+  // Create a new CIconLabel to hold the bitmap image
 
-  FAR NXWidgets::CImage *image =
+  FAR CIconImage *image =
-    new NXWidgets::CImage(m_widgetControl, iconImagePos.x,
+    new CIconImage(m_widgetControl, iconImagePos.x,
-                          iconImagePos.y, iconImageSize.w, iconImageSize.h,
+                   iconImagePos.y, iconImageSize.w, iconImageSize.h,
-                          ibitmap, &m_style);
+                   ibitmap, &m_style);
-  if (image == (FAR NXWidgets::CImage *)0)
+  if (image == (FAR CIconImage *)0)
     {
       twmerr("ERROR: Failed to create image\n");
       return false;
@@ -286,8 +289,9 @@ bool CIconWidget::initialize(FAR CWindow *parent,
   image->enable();
   image->disableDrawing();
   image->setRaisesEvents(true);
+  image->setDraggable(true);
 
-  // Add the CImage to to the containing widget
+  // Add the CIconImage to to the containing widget
 
   image->addWidgetEventHandler(this);
   addWidget(image);
@@ -304,13 +308,13 @@ bool CIconWidget::initialize(FAR CWindow *parent,
       iconTopLabelPos.x = (iconWidgetSize.w - iconTopLabelSize.w) / 2;
     }
 
-  // Create a new CLabel to hold the upper icon title
+  // Create a new CIconLabel to hold the upper icon title
 
-  FAR NXWidgets::CLabel *topLabel =
+  FAR CIconLabel *topLabel =
-    new NXWidgets::CLabel(m_widgetControl, iconTopLabelPos.x,
+    new CIconLabel(m_widgetControl, iconTopLabelPos.x,
-                          iconTopLabelPos.y, iconTopLabelSize.w,
+                   iconTopLabelPos.y, iconTopLabelSize.w,
-                          iconTopLabelSize.h, topString, &m_style);
+                   iconTopLabelSize.h, topString, &m_style);
-  if (topLabel == (FAR NXWidgets::CLabel *)0)
+  if (topLabel == (FAR CIconLabel *)0)
     {
       twmerr("ERROR: Failed to create icon topLabel\n");
       delete image;
@@ -324,6 +328,7 @@ bool CIconWidget::initialize(FAR CWindow *parent,
   topLabel->enable();
   topLabel->disableDrawing();
   topLabel->setRaisesEvents(true);
+  topLabel->setDraggable(true);
 
   // Add the top label to to the containing widget
 
@@ -348,13 +353,13 @@ bool CIconWidget::initialize(FAR CWindow *parent,
           iconBottomLabelPos.x = (iconWidgetSize.w - iconBottomLabelSize.w) / 2;
         }
 
-      // Create a new CLabel to hold the lower icon title
+      // Create a new CIconLabel to hold the lower icon title
 
-      FAR NXWidgets::CLabel *bottomLabel =
+      FAR CIconLabel *bottomLabel =
-        new NXWidgets::CLabel(m_widgetControl, iconBottomLabelPos.x,
+        new CIconLabel(m_widgetControl, iconBottomLabelPos.x,
-                              iconBottomLabelPos.y, iconBottomLabelSize.w,
+                       iconBottomLabelPos.y, iconBottomLabelSize.w,
-                              iconBottomLabelSize.h, bottomString,&m_style);
+                       iconBottomLabelSize.h, bottomString,&m_style);
-      if (bottomLabel == (FAR NXWidgets::CLabel *)0)
+      if (bottomLabel == (FAR CIconLabel *)0)
         {
           twmerr("ERROR: Failed to create icon bottomLabel\n");
           delete topLabel;
@@ -369,6 +374,7 @@ bool CIconWidget::initialize(FAR CWindow *parent,
       bottomLabel->enable();
       bottomLabel->disableDrawing();
       bottomLabel->setRaisesEvents(true);
+      bottomLabel->setDraggable(true);
 
       // Add the top label to to the containing widget
 
@@ -452,10 +458,6 @@ bool CIconWidget::event(FAR struct SEventMsg *eventmsg)
 
 void CIconWidget::handleUngrabEvent(const NXWidgets::CWidgetEventArgs &e)
 {
-  // Exit the dragging state
-
-  m_drag = false;
-
   // Generate the un-grab event
 
   struct SEventMsg msg;
@@ -492,7 +494,7 @@ void CIconWidget::handleDragEvent(const NXWidgets::CWidgetEventArgs &e)
   // We don't care which component of the icon widget was clicked only that
   // we are not currently being dragged
 
-  if (m_drag)
+  if (m_dragging)
     {
       // Generate the event
 
@@ -532,7 +534,7 @@ void CIconWidget::handleDropEvent(const NXWidgets::CWidgetEventArgs &e)
   // When the Drop Event is received, both isClicked and isBeingDragged()
   // will return false.  No checks are performed.
 
-  if (m_drag)
+  if (m_dragging)
     {
       // Yes.. handle the drop event
 
@@ -551,7 +553,7 @@ void CIconWidget::handleClickEvent(const NXWidgets::CWidgetEventArgs &e)
   // We don't care which component of the icon widget was clicked only that
   // we are not currently being dragged
 
-  if (!m_drag)
+  if (!m_dragging)
     {
       // Generate the event
 
@@ -592,7 +594,7 @@ void CIconWidget::handleReleaseEvent(const NXWidgets::CWidgetEventArgs &e)
   // Handle the case where a release event was received, but the
   // window was not dragged.
 
-  if (m_drag)
+  if (m_dragging)
     {
       // Handle the non-drag drop event
 
@@ -612,7 +614,7 @@ void CIconWidget::handleReleaseOutsideEvent(const NXWidgets::CWidgetEventArgs &e
   // Handle the case where a release event was received, but the
   // window was not dragged.
 
-  if (m_drag)
+  if (m_dragging)
     {
       // Handle the non-drag drop event
 
@@ -634,8 +636,8 @@ bool CIconWidget::iconGrab(FAR struct SEventMsg *eventmsg)
   // Indicate that dragging has started but the icon has not
   // yet been moved.
 
-  m_drag  = true;
+  m_dragging = true;
-  m_moved = false;
+  m_moved    = false;
 
   // Get the icon position.
 
@@ -647,9 +649,11 @@ bool CIconWidget::iconGrab(FAR struct SEventMsg *eventmsg)
   m_dragOffset.x = widgetPos.x - eventmsg->pos.x;
   m_dragOffset.y = widgetPos.y - eventmsg->pos.y;
 
+#ifdef CONFIG_TWM4NX_MOUSE
   // Select the grab cursor image
 
   m_twm4nx->setCursorImage(&CONFIG_TWM4NX_GBCURSOR_IMAGE);
+#endif
 
   // Remember the grab cursor size
 
@@ -669,7 +673,7 @@ bool CIconWidget::iconGrab(FAR struct SEventMsg *eventmsg)
 
 bool CIconWidget::iconDrag(FAR struct SEventMsg *eventmsg)
 {
-  if (m_drag)
+ if (m_dragging)
     {
       // Calculate the new icon position
 
@@ -745,23 +749,27 @@ bool CIconWidget::iconUngrab(FAR struct SEventMsg *eventmsg)
       return false;
     }
 
+#ifdef CONFIG_TWM4NX_MOUSE
   // Restore the normal cursor image
 
   m_twm4nx->setCursorImage(&CONFIG_TWM4NX_CURSOR_IMAGE);
+#endif
 
   // There are two possibilities:  (1) The icon was moved.  In this case, we
   // leave the icon up and in its new position.  Or (2) the icon was simply
-  // clicked in which case we need to de-iconify the window.
+  // clicked in which case we need to de-iconify the window.  We also check
+  // that we still have m_dragging == true to handle multiple UNGRAB events.
+  // That happens when we get both the DROP and RELEASE events.
 
-  if (!m_moved)
+  if (m_dragging && !m_moved)
     {
       m_parent->deIconify();
     }
 
   // Indicate no longer dragging
 
-  m_drag = false;
+  m_dragging = false;
-  m_moved = false;
+  m_moved    = false;
 
   return true;
 }

graphics/twm4nx/src/ctwm4nx.cxx

@@ -367,7 +367,8 @@ bool CTwm4Nx::eventLoop(void)
 
       if (!dispatchEvent(&u.eventmsg))
         {
-          twmerr("ERROR: dispatchEvent failed\n");
+          twmerr("ERROR: dispatchEvent() failed, eventID=%u\n",
+                 u.eventmsg.eventID);
           cleanup();
           return false;
         }

include/graphics/twm4nx/ciconwidget.hxx

@@ -80,6 +80,90 @@ namespace Twm4Nx
   class CTwm4Nx;                        // Forward reference
   class CWindow;                        // Forward reference
 
+  /**
+   * Self-dragging versions of CLabel and CImage
+   */
+
+  class CIconLabel : public NXWidgets::CLabel
+  {
+    public:
+
+      /**
+       * Constructor for a label containing a string.
+       *
+       * @param pWidgetControl The controlling widget for the display
+       * @param x The x coordinate of the text box, relative to its parent.
+       * @param y The y coordinate of the text box, relative to its parent.
+       * @param width The width of the textbox.
+       * @param height The height of the textbox.
+       * @param text Pointer to a string to display in the textbox.
+       * @param style The style that the button should use.  If this is not
+       *        specified, the button will use the global default widget
+       *        style.
+       */
+
+      inline CIconLabel(NXWidgets::CWidgetControl *pWidgetControl,
+                        nxgl_coord_t x, nxgl_coord_t y,
+                        nxgl_coord_t width, nxgl_coord_t height,
+                        const NXWidgets::CNxString &text,
+                        NXWidgets::CWidgetStyle *style = (NXWidgets::CWidgetStyle *)0) :
+      NXWidgets::CLabel(pWidgetControl, x, y, width, height, text, style)
+      {
+      }
+
+      /**
+       * Called when the widget is clicked.
+       *
+       * @param x The x coordinate of the click.
+       * @param y The y coordinate of the click.
+       */
+
+      inline void onClick(nxgl_coord_t x, nxgl_coord_t y)
+      {
+        startDragging(x, y);
+      }
+  };
+
+  class CIconImage : public NXWidgets::CImage
+  {
+    public:
+
+      /**
+       * Constructor for an image.
+       *
+       * @param pWidgetControl The controlling widget for the display
+       * @param x The x coordinate of the image box, relative to its parent.
+       * @param y The y coordinate of the image box, relative to its parent.
+       * @param width The width of the textbox.
+       * @param height The height of the textbox.
+       * @param bitmap The source bitmap image.
+       * @param style The style that the widget should use.  If this is not
+       *        specified, the button will use the global default widget
+       *        style.
+       */
+
+      inline CIconImage(NXWidgets::CWidgetControl *pWidgetControl,
+                        nxgl_coord_t x, nxgl_coord_t y,
+                        nxgl_coord_t width, nxgl_coord_t height,
+                        FAR NXWidgets::IBitmap *bitmap,
+                        NXWidgets::CWidgetStyle *style = (NXWidgets::CWidgetStyle *)0) :
+      NXWidgets::CImage(pWidgetControl, x, y, width, height, bitmap, style)
+      {
+      }
+
+      /**
+       * Called when the widget is clicked.
+       *
+       * @param x The x coordinate of the click.
+       * @param y The y coordinate of the click.
+       */
+
+      inline void onClick(nxgl_coord_t x, nxgl_coord_t y)
+      {
+        startDragging(x, y);
+      }
+  };
+
   /**
    * Container class that holds the Icon image and table widgets
    */
@@ -98,9 +182,21 @@ namespace Twm4Nx
       struct nxgl_point_s            m_dragPos;        /**< Last mouse position */
       struct nxgl_point_s            m_dragOffset;     /**< Offset from mouse to window origin */
       struct nxgl_size_s             m_dragCSize;      /**< The grab cursor size */
-      bool                           m_drag;           /**< Drag in-progress */
+      bool                           m_dragging;       /**< Drag in-progress */
       bool                           m_moved;          /**< Icon has been moved */
 
+      /**
+       * Called when the widget is clicked.
+       *
+       * @param x The x coordinate of the click.
+       * @param y The y coordinate of the click.
+       */
+
+      inline void onClick(nxgl_coord_t x, nxgl_coord_t y)
+      {
+        startDragging(x, y);
+      }
+
       /**
        * After the widget has been grabbed, it may be dragged then dropped,
        * or it may be simply "un-grabbed".  Both cases are handled here.

include/graphics/twm4nx/cwindowevent.hxx

@@ -88,7 +88,9 @@ namespace Twm4Nx
        * one.
        */
 
-      virtual ~IDragEvent(void) { }
+      virtual ~IDragEvent(void)
+      {
+      }
 
       /**
        * This function is called when there is any moved of the mouse or

include/graphics/twm4nx/nxterm_config.hxx

@@ -59,9 +59,10 @@
 /**
  * Required settings:
  *
- * CONFIG_HAVE_CXX        : C++ support is required
+ * CONFIG_HAVE_CXX         : C++ support is required
- * CONFIG_NX              : NX must enabled
+ * CONFIG_NX               : NX must enabled
- * CONFIG_NXTERM=y        : For NxTerm support
+ * CONFIG_NXTERM=y         : For NxTerm support
+ * CONFIG_NXTERM_NXKBDIN=y : May be needed if Twm4Nx is managing the keyboard
  */
 
 #ifndef CONFIG_HAVE_CXX
@@ -76,6 +77,18 @@
 #  warning "NxTerm support is required (CONFIG_NXTERM)"
 #endif
 
+// Keyboard input can come from either /dev/console or via Twm4Nx.  If
+// keyboard input comes from Twm4Nx, then CONFIG_NXTERM_NXKBDIN must be
+// defined to support injection of keyboard input from applications.
+// Otherwise, CONFIG_NXTERM_NXKBDIN must not be defined to support use of
+// /dev/console for keyboard input.
+
+#if !defined(CONFIG_TWM4NX_NOKEYBOARD) && !defined(CONFIG_NXTERM_NXKBDIN)
+#  warning "Nxterm needs CONFIG_NXTERM_NXKBDIN for keyboard input"
+#elif defined(CONFIG_TWM4NX_NOKEYBOARD) && defined(CONFIG_NXTERM_NXKBDIN)
+#  warning "Nxterm has no keyboard input.  Undefine CONFIG_NXTERM_NXKBDIN
+#endif
+
 // NxTerm Window /////////////////////////////////////////////////////////////
 
 /**