Final refactoring and implementation of delayed window deletion logic. Works worse now, but the changes are important and need to be checked in now

git-svn-id: https://nuttx.svn.sourceforge.net/svnroot/nuttx/trunk@4747 7fd9a85b-ad96-42d3-883c-3090e2eb8679

NxWidgets/libnxwidgets/include/ibitmap.hxx

@@ -102,6 +102,15 @@ namespace NXWidgets
   class IBitmap
   {
   public:
+    /**
+     * A virtual destructor is required in order to override the IBitmap
+     * destructor.  We do this because if we delete IBitmap, we want the
+     * destructor of the class that inherits from IBitmap to run, not this
+     * one.
+     */
+
+    virtual ~IBitmap(void) { }
+
     /**
      * Get the bitmap's color format.
      *

NxWidgets/libnxwidgets/include/ilistbox.hxx

@@ -102,6 +102,14 @@ namespace NXWidgets
   class IListBox
   {
   public:
+    /**
+     * A virtual destructor is required in order to override the IListBox
+     * destructor.  We do this because if we delete IListBox, we want the
+     * destructor of the class that inherits from IListBox to run, not this
+     * one.
+     */
+
+    virtual ~IListBox(void) { }
 
     /**
      * Add a new option to the widget using default colors.

NxWidgets/libnxwidgets/include/ilistdataeventhandler.hxx

@@ -103,6 +103,15 @@ namespace NXWidgets
   class IListDataEventHandler
   {
   public:
+    /**
+     * A virtual destructor is required in order to override the IListDataEventHandler
+     * destructor.  We do this because if we delete IListDataEventHandler, we want the
+     * destructor of the class that inherits from IListDataEventHandler to run, not this
+     * one.
+     */
+
+    virtual ~IListDataEventHandler(void) { }
+
     /**
      * Handle data changes.
      *

NxWidgets/libnxwidgets/include/inxwindow.hxx

@@ -79,6 +79,14 @@ namespace NXWidgets
   class INxWindow
   {
   public:
+    /**
+     * A virtual destructor is required in order to override the INxWindow
+     * destructor.  We do this because if we delete INxWindow, we want the
+     * destructor of the class that inherits from INxWindow to run, not this
+     * one.
+     */
+
+    virtual ~INxWindow(void) { }
 
     /**
      * Creates a new window.  Window creation is separate from

NxWidgets/libnxwidgets/include/iscrollable.hxx

@@ -102,6 +102,15 @@ namespace NXWidgets
   class IScrollable
   {
   public:
+    /**
+     * A virtual destructor is required in order to override the IScrollable
+     * destructor.  We do this because if we delete IScrollable, we want the
+     * destructor of the class that inherits from IScrollable to run, not this
+     * one.
+     */
+
+    virtual ~IScrollable(void) { }
+
     /**
      * Gets the x coordinate of the virtual canvas.
      *

NxWidgets/libnxwidgets/include/islider.hxx

@@ -99,6 +99,14 @@ namespace NXWidgets
   class ISlider
   {
   public:
+    /**
+     * A virtual destructor is required in order to override the ISlider
+     * destructor.  We do this because if we delete ISlider, we want the
+     * destructor of the class that inherits from ISlider to run, not this
+     * one.
+     */
+
+    virtual ~ISlider(void) { }
 
     /**
      * Get the smallest value that the slider can represent.

NxWidgets/libnxwidgets/include/itextbox.hxx

@@ -115,6 +115,14 @@ namespace NXWidgets
   class ITextBox
   {
   public:
+    /**
+     * A virtual destructor is required in order to override the ITextBox
+     * destructor.  We do this because if we delete ITextBox, we want the
+     * destructor of the class that inherits from ITextBox to run, not this
+     * one.
+     */
+
+    virtual ~ITextBox(void) { }
 
     /**
      * Sets the cursor display mode.