Documentation updates for STR #2142 (protected draw methods).

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3@6665 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

CHANGES

@@ -1,5 +1,6 @@
 CHANGES IN FLTK 1.3.0
 
+	- All draw() methods of widgets are now protected (STR #2142).
 	- The new configure option --enable-x11 (lowercase 'x') enables
 	  cygwin builds under Windows (with --enable-cygwin) to use X11
 	  instead of GDI drawing (STR #2147) and is ignored otherwise.

FL/Fl_Widget.H

@@ -179,6 +179,15 @@ public:
       instead.
 
       Override this function to draw your own widgets.
+
+      If you ever need to call another widget's draw method <I>from within your
+      own draw method</I>, e.g. for an embedded scrollbar, you must downcast the
+      embedded widget's pointer to Fl_Widget* and call the virtual draw() method.
+
+      \code
+        Fl_Widget *s = &scroll;		// scroll is an embedded Fl_Scrollbar
+	s->draw();			// calls Fl_Scrollbar::draw()
+      \endcode
    */
   virtual void draw() = 0;
 

documentation/src/drawing.dox

@@ -13,17 +13,12 @@ Calling these functions at other places will result in undefined behavior!
     To write code here, you must subclass one of the existing Fl_Widget
     classes and implement your own version of draw().
 
-\li The most common place is inside the virtual method
-    <A href="subclassing.html#draw"><tt>Fl_Widget::draw()</tt></A>. 
-    To write code here, you must subclass one of the existing Fl_Widget
-    classes and implement your own version of draw().
-
 \li You can also write <A href="common.html#boxtypes">boxtypes</A> and
     <A href="common.html#labeltypes">labeltypes</A>. These are small
     procedures that can be called by existing
-    <A HREF="subclassing.html#draw"><tt>Fl_Widget::draw()</tt></A>
-    methods. These "types" are identified by an 8-bit index that is stored
-    in the widget's box(), labeltype(), and possibly other properties.
+    Fl_Widget::draw() methods. These "types" are identified by an 8-bit
+    index that is stored in the widget's box(), labeltype(), and possibly
+    other properties.
 
 \li You can call Fl_Window::make_current() to do incremental update of a
     widget. Use Fl_Widget::window() to find the window.