/**

 \page development Developer Information

This chapter describes FLTK development and documentation.

\note	documentation with doxygen will be described here.


<H2>Example</H2>

\note

In the following code example(s) "*" will be replaced by "#"
as a temporary solution.

\code


/## \file
   Fl_Clock, Fl_Clock_Output widgets . #/


/##
  \class Fl_Clock_Output
  \brief This widget can be used to display a program-supplied time.
  
  The time shown on the clock is not updated. To display the current time,
  use Fl_Clock instead.

  \image html clock.gif 
  \image latex clock.eps "" width=10cm 
  \image html round_clock.gif
  \image latex clock.eps "" width=10cm 
  \image html round_clock.eps "" width=10cm #/

  /##
    Returns the displayed time.
    Returns the time in seconds since the UNIX epoch (January 1, 1970).
    \see value(ulong)
   #/
  ulong value() const {return value_;}

/##
  Set the displayed time.
  Set the time in seconds since the UNIX epoch (January 1, 1970).
  \param[in] v seconds since epoch
  \see value()
 #/
void Fl_Clock_Output::value(ulong v) {
 [...]
}

/##
  Create an Fl_Clock widget using the given position, size, and label string.
  The default boxtype is \c FL_NO_BOX.
  \param[in] X, Y, W, H position and size of the widget
  \param[in] L widget label, default is no label
 #/
Fl_Clock::Fl_Clock(int X, int Y, int W, int H, const char #L)
  : Fl_Clock_Output(X, Y, W, H, L) {}

/##
  Create an Fl_Clock widget using the given boxtype, position, size, and
  label string.
  \param[in] t boxtype
  \param[in] X, Y, W, H position and size of the widget
  \param[in] L widget label, default is no label
 #/
Fl_Clock::Fl_Clock(uchar t, int X, int Y, int W, int H, const char #L)
  : Fl_Clock_Output(X, Y, W, H, L) {
  type(t);
  box(t==FL_ROUND_CLOCK ? FL_NO_BOX : FL_UP_BOX);
}


\endcode


\note

From Duncan: (will be removed later, just for now as a reminder)

5. I've just added comments for the fl_color_chooser() functions, and
   in order to keep them and the general Function Reference information
   for them together, I created a new doxygen group, and used \\ingroup
   in the three comment blocks. This creates a new Modules page (which
   may not be what we want) with links to it from the File Members and
   Fl_Color_Chooser.H pages. It needs a bit more experimentation on my
   part unless someone already knows how this should be handled. (Maybe
   we can add it to a functions.dox file that defines a functions group
   and do that for all of the function documentation?)

\b Update: the trick is not to create duplicate entries in a new group, but
   to move the function information into the doxygen comments for the
   class, and use the navigation links provided. Simply using \\relatesalso
   as the first doxygen command in the function's comment puts it in the
   appropriate place. There is no need to have \\defgroup and \\ingroup as
   well, and indeed they don't work. So, to summarize:
\code
Gizmo.H
  /## \class Gizmo
      A gizmo that does everything
    #/
  class Gizmo {
    etc
  };
  extern int popup_gizmo(...);

Gizmo.cxx:
  /## \relatesalso Gizmo
      Pops up a gizmo dialog with a Gizmo in it
    #/
  int popup_gizmo(...);
\endcode

<H3>Example comment:</H3>

You can use HTML comment statements to embed comments in doxygen comment blocks.
These comments will not be visible in the generated document.

    The following text is a developer comment.
    <!-- *** This *** is *** invisible *** -->
    This will be visible again.

\code
    The following text is a developer comment.
    <!-- *** This *** is *** invisible *** -->
    This will be visible again.
\endcode


<H3>Different Headlines:</H3>

\code
    <H1>Headline in big text (H1)</H1>
    <H2>Headline in big text (H2)</H2>
    <H3>Headline in big text (H3)</H3>
    <H4>Headline in big text (H4)</H4>
\endcode

    <H1>Headline in big text (H1)</H1>
    <H2>Headline in big text (H2)</H2>
    <H3>Headline in big text (H3)</H3>
    <H4>Headline in big text (H4)</H4>


\section development_non-ascii Non-ASCII characters

	if you came here from below: back to \ref development_links

\code
    Doxygen understands many HTML quoting characters like
    &quot;, &uuml;, &ccedil;, &Ccedil;, but not all HTML quoting characters.
\endcode

This will appear in the document:

    Doxygen understands many HTML quoting characters like
    &quot;, &uuml;, &ccedil;, &Ccedil;, but not all HTML quoting characters.

For further informations about quoting see 
    \b http://www.stack.nl/~dimitri/doxygen/htmlcmds.html

<H3>Example with UTF-8 encoded text</H3>

\code

    <P>Assuming that the following source code was written on MS Windows, 
    this example will output the correct label on OS X and X11 as well.
    Without the conversion call, the label on OS X would read 
    <tt>Fahrvergn¸gen</tt> with a deformed umlaut u ("cedille",
    html "&cedil;").
    \#code
      btn = new Fl_Button(10, 10, 300, 25);
      btn->copy_label(fl_latin1_to_local("Fahrvergnügen"));
    \#endcode

    \note   If your application uses characters that are not part of both
	    encodings, or it will be used in areas that commonly use different
	    code pages, you might consider upgrading to FLTK 2 which supports
	    UTF-8 encoding. 

    \todo   This is an example todo entry, please ignore !

\endcode

This will appear in the document:

    <P>Assuming that the following source code was written on MS Windows, 
    this example will output the correct label on OS X and X11 as well.
    Without the conversion call, the label on OS X would read 
    <tt>Fahrvergn¸gen</tt> with a deformed umlaut u ("cedille",
    html "&cedil;").
    \#code
      btn = new Fl_Button(10, 10, 300, 25);
      btn->copy_label(fl_latin1_to_local("Fahrvergnügen"));
    \#endcode

    \note   If your application uses characters that are not part of both
	    encodings, or it will be used in areas that commonly use different
	    code pages, you might consider upgrading to FLTK 2 which supports
	    UTF-8 encoding. 

    \todo   This is an example todo entry, please ignore !

\section development_structure Document Structure

  \li	\b \\page	creates a named page
  \li	\b \\section	creates a named section within that page
  \li	\b \\subsection	creates a named subsection within the current section
  \li	\b \\subsubsection creates a named subsubsection within the current subsection

All these statements take a "name" as their first argument, and a title
as their second argument. The title can contain spaces.

The page, section, and subsection titles are formatted in blue color and
a size like \b "<H1>", \b "<H2>", and \b "<H3>", and \b "<H4>", respectively.

By <b>FLTK documentation convention</b>, a file like this one with a doxygen
documentation chapter has the name <b>"<chapter>.dox".</b>
The \b \\page statement at the top of the page is 
<b>"\page <chapter> This is the title"</b>.
Sections within a documentation page must be called \b "<chapter>_<section>",
where \b "<chapter>" is the name part of the file, and \b "<section>" is a
unique section name within the page that can be referenced in links. The
same for subsections and subsubsections.

These doxygen page and section commands work only in special documentation
chapters, not within normal source or header documentation blocks. However,
links \b from normal (e.g. class) documentation \b to documentation sections
\b do \b work.

This page has
  \code
	\page development I - Developer Information
  \endcode
at its top.

This section is
  \code
	\section development_structure Document structure
  \endcode

The following section is
  \code
	\section development_links Creating Links
  \endcode


\section development_links Creating Links

Links to other documents and external links can be embedded with
  \li	normal HTML links
  \li	HTML links without markup - doxygen creates "http://..."
  	links automatically
  \li	links to other doxygen chapters with the \\ref statments
  \li	links to named sections within the same or other doxygen chapters,
  	if they are defined there with a \\section statement

\code
    see chapter \ref unicode creates a link to the named chapter unicode
    that has been created with a \subpage statement.

    see <a href="drawing.html#character_encoding">chapter 5</a> creates
    a link to a named html anchor "character_encoding" within the same file.

    For further informations about quoting see
    http://www.stack.nl/~dimitri/doxygen/htmlcmds.html

    Bold link text: you can see the <b>online documentation</b>
    of FLTK 1.3 at \b http://www.fltk.org/doc-1.3/index.html
    
    see section \ref development_non-ascii
\endcode

appears as:

    see chapter \ref unicode creates a link to the named chapter unicode
    that has been created with a \\subpage statement.

    see <a href="drawing.html#character_encoding">chapter 5</a> creates
    a link to a named html anchor "character_encoding" within the same file.

    For further informations about quoting see
    http://www.stack.nl/~dimitri/doxygen/htmlcmds.html

    Bold link text: you can see the <b>online documentation</b>
    of FLTK 1.3 at \b http://www.fltk.org/doc-1.3/index.html
    
    see section \ref development_non-ascii

\section development_old-links Changing Old Links

Old HTML links and anchors in text documentation pages should be changed
as follows:

\code
<H2><A name="event_xxx">Fl::event_*() methods</A></H2>

becomes:

<A NAME="event_xxx"></A> <!-- For old HTML links only ! -->
\section events_event_xxx Fl::event_*() methods
\endcode

The additional HTML "<A NAME=...>" statement is temporary needed, until
all links (references) are modified, then:

\code
<H2><A name="event_xxx">Fl::event_*() methods</A></H2>

becomes:

\section events_event_xxx Fl::event_*() methods
\endcode

The "\section" statement can also be a "\subsection" or "\subsubsection"
statement.

The references (in this example from index.dox) are changed as follows:

\code

 \subpage events

    <B>
      <UL>
	<LI><A HREF="events.html#event_xxx">Fl::event_*() methods</A></LI>
	<LI><A HREF="events.html#propagation">Event Propagation</A></LI>
      </UL>
    </B>

becomes:

 \subpage events

    <b>
	\li \ref events_event_xxx
	\li \ref events_propagation
    </b>

\endcode


\section development_paragraphs Paragraph Layout

There is no real need to use HTML \<P\> and \</P\> tags within the text
to tell doxygen to start or stop a paragraph. In most cases, when doxygen
encounters a blank line or some, but not all, \b \\commands in the text it
knows that it as reached the start or end of a paragraph. Doxygen also
offers the \b \\par command for special paragraph handling. It can be used
to provide a paragraph title and also to indent a paragraph. Unfortunately
\b \\par won't do what you expect if you want to have doxygen links and
sometimes html tags don't work either.

  <!-- use verbatim rather than code to avoid links to code reference -->
  \verbatim
    \par Normal Paragraph with title

    This paragraph will have a title, but because there is a blank line
    between the \par and the text, it will have the normal layout.

    \par Indented Paragraph with title
    This paragraph will also have a title, but because there is no blank
    line between the \par and the text, it will be indented.

    \par
    It is also possible to have an indented paragraph without title.
    This is how you indent subsequent paragraphs.

    \par No link to Fl_Widget::draw()
    Note that the paragraph title is treated as plain text.
    Doxygen type links will not work.
    HTML characters and tags may or may not work.

    Fl_Widget::draw() links and &quot;html&quot; tags work<br>
    \par
    Use a single line ending with <br> for complicated paragraph titles.
  \endverbatim

The above code produces the following paragraphs:

    \par Normal Paragraph with title

    This paragraph will have a title, but because there is a blank line
    between the \\par and the text, it will have the normal layout.

    \par Indented Paragraph with title
    This paragraph will also have a title, but because there is no blank
    line between the \\par and the text, it will be indented.

    \par
    It is also possible to have an indented paragraph without title.
    This is how you indent subsequent paragraphs.

    \par No link to Fl_Widget::draw()
    Note that the paragraph title is treated as plain text.
    Doxygen type links will not work.
    HTML characters and tags may or may not work.

    Fl_Widget::draw() links and &quot;html&quot; tags work<br>
    \par
    Use a single line ending with \<br\> for complicated paragraph titles.


\section development_html_footer Hack for missing "tiny.gif" file

  \todo
	*HACK* : include image file for footer. Doxygen does not include
  	the file "tiny.gif" from "html_footer" in its output html dir.
	Find out, how this can be done, or avoid using an image in
	the HTML footer.

  \image html tiny.gif
  \image latex tiny.eps "" width=2cm	

\section development_navigation_test Navigation Elements

Each introduction (tutorial) page ends with navigation elements. These
elements must only be included in the html documentation, therefore
they must be separated with \\htmlonly and \\endhtmlonly.

Example navigation links:

\verbatim
\htmlonly
<hr>
<a class="el" href="index.html">[Index]</a> &nbsp;&nbsp;
<a class="el" href="migration_1_3.html">[Previous] Migrating Code from FLTK 1.1 to 1.3</a>&nbsp;&nbsp;
<a class="el" href="license.html">[Next] Software License</a>
\endhtmlonly
\endverbatim

Now replaced by:
\verbatim
\htmlonly
<hr>
<table summary="navigation bar" width="100%" border="0">
<tr>
  <td width="45%" align="LEFT">
    <a class="el" href="migration_1_3.html">
    [Prev]
    Migrating Code from FLTK 1.1 to 1.3
    </a>
  </td>
  <td width="10%" align="CENTER">
    <a class="el" href="main.html">[Index]</a>
  </td>
  <td width="45%" align="RIGHT">
    <a class="el" href="license.html">
    Software License
    [Next]
    </a>
  </td>
</tr>
</table>
\endhtmlonly
\endverbatim


\htmlonly
<hr>
<table summary="navigation bar" width="100%" border="0">
<tr>
  <td width="45%" align="LEFT">
    <a class="el" href="migration_1_3.html">
    [Prev]
    Migrating Code from FLTK 1.1 to 1.3
    </a>
  </td>
  <td width="10%" align="CENTER">
    <a class="el" href="main.html">[Index]</a>
  </td>
  <td width="45%" align="RIGHT">
    <a class="el" href="license.html">
    Software License
    [Next]
    </a>
  </td>
</tr>
</table>
\endhtmlonly

*/
