+@page overview_html wxHTML Overview
+
+The wxHTML library provides classes for parsing and displaying HTML.
+It is not intended to be a high-end HTML browser. If you are looking for
+something like that try <http://www.mozilla.org/>.
+
+wxHTML can be used as a generic rich text viewer - for example to display
+a nice About Box (like those of GNOME apps) or to display the result of
+database searching. There is a wxFileSystem class which allows you to use
+your own virtual file systems.
+
+wxHtmlWindow supports tag handlers. This means that you can easily
+extend wxHtml library with new, unsupported tags. Not only that,
+you can even use your own application-specific tags!
+
+See @c src/html/m_*.cpp files for details.
+
+There is a generic wxHtmlParser class, independent of wxHtmlWindow.
+
+@li @ref overview_html_quickstart
+@li @ref overview_html_printing
+@li @ref overview_html_helpformats
+@li @ref overview_html_filters
+@li @ref overview_html_cells
+@li @ref overview_html_handlers
+@li @ref overview_html_supptags
+
+
+<hr>
+
+
+@section overview_html_quickstart wxHTML quick start
+
+@subsection overview_html_quickstart_disphtml Displaying HTML
+
+First of all, you must include @c wx/wxhtml.h.
+
+Class wxHtmlWindow (derived from ::wxScrolledWindow) is used to display HTML documents.
+
+It has two important methods: wxHtmlWindow::LoadPage and wxHtmlWindow::SetPage.
+LoadPage loads and displays HTML file while SetPage displays directly the
+passed @b string. See the example:
+
+@code
+ mywin -> LoadPage("test.htm");
+ mywin -> SetPage("htmlbody"
+ "h1Error/h1"
+ "Some error occurred :-H)"
+ "/body/hmtl");
+@endcode
+
+@subsection overview_html_quickstart_disphelp Displaying Help
+
+See wxHtmlHelpController.
+
+@subsection overview_html_quickstart_settingup Setting up wxHtmlWindow
+
+Because wxHtmlWindow is derived from ::wxScrolledWindow and not from
+wxFrame, it doesn't have visible frame. But the user usually wants to see
+the title of HTML page displayed somewhere and the frame's titlebar is
+the ideal place for it.
+
+wxHtmlWindow provides 2 methods in order to handle this:
+wxHtmlWindow::SetRelatedFrame and wxHtmlWindow::SetRelatedStatusBar.
+See the example:
+
+@code
+ html = new wxHtmlWindow(this);
+ html -> SetRelatedFrame(this, "HTML : %%s");
+ html -> SetRelatedStatusBar(0);
+@endcode
+
+The first command associates the HTML object with its parent frame
+(this points to wxFrame object there) and sets the format of the title.
+Page title "Hello, world!" will be displayed as "HTML : Hello, world!"
+in this example.
+
+The second command sets which frame's status bar should be used to display
+browser's messages (such as "Loading..." or "Done" or hypertext links).
+
+@subsection overview_html_quickstart_custom Customizing wxHtmlWindow
+
+You can customize wxHtmlWindow by setting font size, font face and
+borders (space between border of window and displayed HTML). Related functions:
+
+@li wxHtmlWindow::SetFonts
+@li wxHtmlWindow::SetBorders
+@li wxHtmlWindow::ReadCustomization
+@li wxHtmlWindow::WriteCustomization
+
+The last two functions are used to store user customization info wxConfig stuff
+(for example in the registry under Windows, or in a dotfile under Unix).
+
+
+
+@section overview_html_printing HTML Printing
+
+The wxHTML library provides printing facilities with several levels of complexity.
+The easiest way to print an HTML document is to use the wxHtmlEasyPrinting class.
+
+It lets you print HTML documents with only one command and you don't have to worry
+about deriving from the wxPrintout class at all. It is only a simple wrapper around the
+wxHtmlPrintout, normal wxWidgets printout class.
+
+And finally there is the low level class wxHtmlDCRenderer which you can use to
+render HTML into a rectangular area on any DC.
+
+It supports rendering into multiple rectangles with the same
+width. (The most common use of this is placing one rectangle on each page or
+printing into two columns.)
+
+
+@section overview_html_helpformats Help Files Format
+
+wxHTML library uses a reduced version of MS HTML Workshop format.
+Tex2RTF can produce these files when generating HTML, if you set
+@b htmlWorkshopFiles to @true in your tex2rtf.ini file.
+(See wxHtmlHelpController for help controller description.)
+
+A @b book consists of three files: the header file, the contents file
+and the index file.
+
+You can make a regular zip archive of these files, plus the HTML and any
+image files, for wxHTML (or helpview) to read; and the @c .zip file can
+optionally be renamed to @c .htb.
+
+@subsection overview_html_helpformats_hhp Header file (.hhp)
+
+The header file must contain these lines (and may contain additional lines
+which are ignored):
+
+@code
+Contents file=filename.hhc
+Index file=filename.hhk
+Title=title of your book
+Default topic=default page to be displayed.htm
+@endcode
+
+All filenames (including the Default topic) are relative to the
+location of the @c .hhp file.
+
+@note For localization, in addition the @c .hhp file may contain the line
+ @code
+ Charset=rfc_charset
+ @endcode
+ which specifies what charset (e.g. "iso8859_1") was used in contents
+ and index files. Please note that this line is incompatible with
+ MS HTML Help Workshop and it would either silently remove it or complain
+ with some error. See also @ref overview_nonenglish.
+
+@subsection overview_html_helpformats_hhc Contents file (.hhc)
+
+Contents file has HTML syntax and it can be parsed by regular HTML parser.
+It contains exactly one list (@c <ul>....@c </ul> statement):
+
+@code
+<ul>
+
+<li><object type="text/sitemap">
+ <param name="Name" value="@topic name@">
+ <param name="ID" value=@numeric_id@>
+ <param name="Local" value="@filename.htm@">
+ </object>
+<li><object type="text/sitemap">
+ <param name="Name" value="@topic name@">
+ <param name="ID" value=@numeric_id@>
+ <param name="Local" value="@filename.htm@">
+ </object>
+...
+</ul>
+@endcode
+
+You can modify value attributes of param tags.
+The <em>topic name</em> is name of chapter/topic as is displayed in
+contents, <em>filename.htm</em> is the HTML page name (relative to the @c .hhp file)
+and <em>numeric_id</em> is optional - it is used only when you use wxHtmlHelpController::Display(int).
+
+Items in the list may be nested - one @c <li> statement may contain a @c <ul> sub-statement:
+
+@code
+<ul>
+
+<li><object type="text/sitemap">
+ <param name="Name" value="Top node">
+ <param name="Local" value="top.htm">
+ </object>
+ <ul>
+ <li><object type="text/sitemap">
+ <param name="Name" value="subnode in topnode">
+ <param name="Local" value="subnode1.htm">
+ </object>
+ ...
+ </ul>
+
+<li><object type="text/sitemap">
+ <param name="Name" value="Another Top">
+ <param name="Local" value="top2.htm">
+ </object>
+...
+
+</ul>
+@endcode
+
+@subsection overview_html_helpformats_hhk Index file (.hhk)
+
+Index files have same format as contents file except that ID params are ignored
+and sublists are @b not allowed.
+
+
+@section overview_html_filters Input Filters
+
+The wxHTML library provides a mechanism for reading and displaying
+files of many different file formats.
+
+wxHtmlWindow::LoadPage can load not only HTML files but any known file.
+To make a file type known to wxHtmlWindow you must create a wxHtmlFilter filter and
+register it using wxHtmlWindow::AddFilter.
+
+
+@section overview_html_cells Cells and Containers
+
+This article describes mechanism used by wxHtmlWinParser and
+wxHtmlWindow to parse and display HTML documents.
+
+@subsection overview_html_cells_cells Cells
+
+You can divide any text (or HTML) into small fragments. Let's call these
+fragments @b cells. Cell is for example one word, horizontal line, image
+or any other part of document. Each cell has width and height (except special
+"magic" cells with zero dimensions - e.g. colour changers or font changers).
+See wxHtmlCell.
+
+@subsection overview_html_cells_containers Containers
+
+Container is kind of cell that may contain sub-cells. Its size depends
+on number and sizes of its sub-cells (and also depends on width of window).
+See wxHtmlContainerCell, wxHtmlCell::Layout. This image shows the cells and
+containers:
+
+@image html overview_html_contbox.png
+
+@subsection overview_html_cells_conttaghandler Using Containers in Tag Handler
+
+wxHtmlWinParser provides a user-friendly way of managing containers.
+It is based on the idea of opening and closing containers.
+
+Use wxHtmlWinParser::OpenContainer to open new a container @e within an already
+opened container.
+This new container is a @e sub-container of the old one. (If you want to create a
+new container with the same depth level you can call @c CloseContainer(); OpenContainer();.)
+
+Use wxHtmlWinParser::CloseContainer to close the container.
+This doesn't create a new container with same depth level but it returns "control"
+to the parent container. See explanation:
+
+@image html overview_html_cont.png
+
+There clearly must be same number of calls to OpenContainer as to
+CloseContainer.
+
+@subsubsection overview_html_cells_conttaghandler_example Example
+
+This code creates a new paragraph (container at same depth level)
+with "Hello, world!":
+
+@code
+m_WParser -> CloseContainer();
+c = m_WParser -> OpenContainer();
+
+m_WParser -> AddText("Hello, ");
+m_WParser -> AddText("world!");
+
+m_WParser -> CloseContainer();
+m_WParser -> OpenContainer();
+@endcode
+
+and here is image of the situation:
+
+@image html overview_html_hello.png
+
+You can see that there was an opened container before the code was executed.
+We closed it, created our own container, then closed our container and opened
+new container.
+
+The result was that we had @e same depth level after executing.
+This is general rule that should be followed by tag handlers:
+leave depth level of containers unmodified (in other words, number of
+OpenContainer and CloseContainer calls should be same within
+wxHtmlTagHandler::HandleTag's body).
+
+Notice that it would be usually better to use wxHtmlContainerCell::InsertCell instead
+of adding text to the parser directly.
+
+
+@section overview_html_handlers Tag Handlers
+
+The wxHTML library provides architecture of pluggable @e tag handlers.
+Tag handler is class that understands particular HTML tag (or tags) and is
+able to interpret it.
+
+wxHtmlWinParser has a static table of @b modules.
+Each module contains one or more tag handlers. Each time a new wxHtmlWinParser
+object is constructed all modules are scanned and handlers are added
+to wxHtmlParser's list of available handlers (note: wxHtmlParser's list
+is non-static).
+
+@subsection overview_html_handlers_howworks How it works
+
+Common tag handler's wxHtmlTagHandler::HandleTag method works in four steps:
+
+@li Save state of parent parser into local variables
+@li Change parser state according to tag's params
+@li Parse text between the tag and paired ending tag (if present)
+@li Restore original parser state
+
+See wxHtmlWinParser for methods for modifying parser's state.
+In general you can do things like opening/closing containers, changing colors, fonts etc.
+
+@subsection overview_html_handlers_custom Providing own tag handlers
+
+You should create a new .cpp file and place the following lines into it:
+
+@code
+#include <mod_templ.h>
+#include <forcelink.h>
+FORCE_LINK_ME(yourmodulefilenamewithoutcpp)
+@endcode
+
+Then you must define handlers and one module.
+
+@subsection overview_html_handlers_tag Tag handlers
+
+The handler is derived from wxHtmlWinTagHandler (or directly from wxHtmlTagHandler).
+
+You can use set of macros to define the handler (see src/html/m_*.cpp files
+for details). Handler definition must start with @b TAG_HANDLER_BEGIN macro
+and end with @b TAG_HANDLER_END macro.
+
+I strongly recommend to have a look at @e include/wxhtml/mod_templ.h file.
+Otherwise you won't understand the structure of macros.
+
+See macros reference:
+@li @b TAG_HANDLER_BEGIN(@e name, @e tags):
+ Starts handler definition. @e name is handler identifier (in fact
+ part of class name), @e tags is string containing list of tags
+ supported by this handler (in uppercase). This macro derives new class from
+ wxHtmlWinTagHandler and implements it is wxHtmlTagHandler::GetSupportedTags method.
+ Example: TAG_HANDLER_BEGIN(FONTS, "B,I,U,T")
+
+@li @b TAG_HANDLER_VARS:
+ This macro starts block of variables definitions. (Variables are identical
+ to class attributes.) Example:
+
+ @code
+ TAG_HANDLER_BEGIN(VARS_ONLY, "CRAZYTAG")
+ TAG_HANDLER_VARS
+ int my_int_var;
+ wxString something_else;
+ TAG_HANDLER_END(VARS_ONLY)
+ @endcode
+
+ This macro is used only in rare cases.
+
+@li @b TAG_HANDLER_CONSTR(@e name):
+ This macro supplies object constructor. @e name is same name as the one
+ from TAG_HANDLER_BEGIN macro. Body of constructor follow after
+ this macro (you must use { and } ). Example:
+
+ @code
+ TAG_HANDLER_BEGIN(VARS2, "CRAZYTAG")
+ TAG_HANDLER_VARS
+ int my_int_var;
+ TAG_HANDLER_CONSTR(vars2)
+ { // !!!!!!
+ my_int_var = 666;
+ } // !!!!!!
+ TAG_HANDLER_END(VARS2)
+ @endcode
+
+ Never used in wxHTML :-)
+
+@li @b TAG_HANDLER_PROC(@e varib):
+ This is very important macro. It defines wxHtmlTagHandler::HandleTag
+ method. @e varib is name of parameter passed to the method, usually
+ @e tag. Body of method follows after this macro.
+ Note than you must use { and } !
+ Example:
+
+ @code
+ TAG_HANDLER_BEGIN(TITLE, "TITLE")
+ TAG_HANDLER_PROC(tag)
+ {
+ printf("TITLE found...\n");
+ }
+ TAG_HANDLER_END(TITLE)
+ @endcode
+
+@li @b TAG_HANDLER_END(@e name):
+ Ends definition of tag handler @e name.
+
+@subsection overview_html_handlers_modules Tags Modules
+
+You can use set of 3 macros TAGS_MODULE_BEGIN, TAGS_MODULE_ADD and
+TAGS_MODULE_END to inherit new module from
+wxHtmlTagsModule and to create instance of it.
+
+See macros reference:
+
+@li @b TAGS_MODULE_BEGIN(@e modname):
+ Begins module definition. @e modname is part of class name and must be unique.
+@li @b TAGS_MODULE_ADD(@e name):
+ Adds the handler to this module. @e name is the identifier from TAG_HANDLER_BEGIN.
+@li @b TAGS_MODULE_END(@e modname):
+ Ends the definition of module.
+ Example:
+
+ @code
+ TAGS_MODULE_BEGIN(Examples)
+ TAGS_MODULE_ADD(VARS_ONLY)
+ TAGS_MODULE_ADD(VARS2)
+ TAGS_MODULE_ADD(TITLE)
+ TAGS_MODULE_END(Examples)
+ @endcode
+
+
+@section overview_html_supptags Tags supported by wxHTML
+
+wxHTML is not full implementation of HTML standard. Instead, it supports most
+common tags so that it is possible to display @e simple HTML documents with it.
+(For example it works fine with pages created in Netscape Composer or generated by tex2rtf).
+
+Following tables list all tags known to wxHTML, together with supported parameters.
+
+A tag has general form of @c tagname param_1 param_2 ... param_n where param_i is
+either @c paramname="paramvalue" or @c paramname=paramvalue - these two are equivalent.
+Unless stated otherwise, wxHTML is case-insensitive.
+
+@subsection overview_html_supptags_commonvalues Table of common parameter values
+
+We will use these substitutions in tags descriptions:
+
+@code
+[alignment] CENTER
+ LEFT
+ RIGHT
+ JUSTIFY
+
+[v_alignment] TOP
+ BOTTOM
+ CENTER
+
+[color] HTML 4.0-compliant colour specification
+
+[fontsize] -2
+ -1
+ +0
+ +1
+ +2
+ +3
+ +4
+ 1
+ 2
+ 3
+ 4
+ 5
+ 6
+ 7
+
+[pixels] integer value that represents dimension in pixels
+
+[percent] i%
+ where i is integer
+
+[url] an URL
+
+[string] text string
+
+[coords] c(1),c(2),c(3),...,c(n)
+ where c(i) is integer
+@endcode
+
+
+@subsection overview_html_supptags_list List of supported tags
+
+@code
+A NAME=[string]
+ HREF=[url]
+ TARGET=[target window spec]
+ADDRESS
+AREA SHAPE=POLY
+ SHAPE=CIRCLE
+ SHAPE=RECT
+ COORDS=[coords]
+ HREF=[url]
+B
+BIG
+BLOCKQUOTE
+BODY TEXT=[color]
+ LINK=[color]
+ BGCOLOR=[color]
+BR ALIGN=[alignment]
+CENTER
+CITE
+CODE
+DD
+DIV ALIGN=[alignment]
+DL
+DT
+EM
+FONT COLOR=[color]
+ SIZE=[fontsize]
+ FACE=[comma-separated list of facenames]
+HR ALIGN=[alignment]
+ SIZE=[pixels]
+ WIDTH=[percent|pixels]
+ NOSHADE
+H1
+H2
+H3
+H4
+H5
+H6
+I
+IMG SRC=[url]
+ WIDTH=[pixels]
+ HEIGHT=[pixels]
+ ALIGN=TEXTTOP
+ ALIGN=CENTER
+ ALIGN=ABSCENTER
+ ALIGN=BOTTOM
+ USEMAP=[url]
+KBD
+LI
+MAP NAME=[string]
+META HTTP-EQUIV="Content-Type"
+ CONTENT=[string]
+OL
+P ALIGN=[alignment]
+PRE
+SAMP
+SMALL
+STRIKE
+STRONG
+SUB
+SUP
+TABLE ALIGN=[alignment]
+ WIDTH=[percent|pixels]
+ BORDER=[pixels]
+ VALIGN=[v_alignment]
+ BGCOLOR=[color]
+ CELLSPACING=[pixels]
+ CELLPADDING=[pixels]
+TD ALIGN=[alignment]
+ VALIGN=[v_alignment]
+ BGCOLOR=[color]
+ WIDTH=[percent|pixels]
+ COLSPAN=[pixels]
+ ROWSPAN=[pixels]
+ NOWRAP
+TH ALIGN=[alignment]
+ VALIGN=[v_alignment]
+ BGCOLOR=[color]
+ WIDTH=[percent|pixels]
+ COLSPAN=[pixels]
+ ROWSPAN=[pixels]
+TITLE
+TR ALIGN=[alignment]
+ VALIGN=[v_alignment]
+ BGCOLOR=[color]
+TT
+U
+UL
+@endcode
+
+*/
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