NAME HTML::Menu::Hierarchical - HTML Hierarchical Menu Generator SYNOPSIS my $menu_obj = HTML::Menu::Hierarchical->new($conf, \&callback, $params); my $html = $menu_obj->generateMenu($menu_item); or my $menu_obj = HTML::Menu::Hierarchical->new($conf, [ $obj, $method ]); my $html = $menu_obj->generateMenu($menu_item); or my $menu_obj = HTML::Menu::Hierarchical->new($conf, $std_callback_name); my $html = $menu_obj->generateMenu($menu_item); In the first case, the callback is a function. In the second, the callback is a method called on the given object. In the third example, the callback is the name of a standard callback defined by HTML::Menu::Hierarchical itself (see the section on callback functions/methods). The $conf parameter is a navigation configuration data structure (described below). The $params parameter is an optional hash reference containing parameters pertaining to the menu as a whole. Recognized parameters are: first_with_url If this is set to a true value and you are using the 'url' field in the info hash (see below) in the configuration to specify the url for the menu item, then if a menu item is chosen that does not have a url configured, the url for that menu item will be changed to the url of the first child menu item that has a url configured. This works by looking at the items first child, then at that child's first child, and so on. It does not look at the second child. open_all This has the same effect as the open_all parameter in the menu configuration structure mentioned below, except that it affects the entire menu hierarchy. old_style_url When using the utilities urlEncodeVars() and addArgsToUrl(), this parameter controls which separator is used to separate key/value pairs in the generated query string. Setting old_style_url to a true value will cause an ampersand ('&') to be used as the separator. new_style_url When using the utilities urlEncodeVars() and addArgsToUrl(), this parameter controls which separator is used to separate key/value pairs in the generated query string. Setting new_style_url to a true value will cause a semicolon (';') to be used as the separator, as recommended by the W3C. This will become the default in a later release. DESCRIPTION HTML::Menu::Hierarchical provides a way to easily generate a hierarchical HTML menu without forcing a specific layout. All output is provided by your own callbacks (subroutine refs) and your own navigation configuration. configuration data structure A navigation configuration is a reference to an array whose elements are hashrefs. Each hash contains configuration information for one menu item and its children, if any. Consider the following example: my $conf = [ { name => 'top_button_1', info => { text => 'Top Level Button 1', url => '/' }, open => 1, # force this item's children to be displayed children => [ { name => 'button_1_level_2', info => { text => "Child 1 of Button 1", url => '/child1.cgi' }, }, ] }, { name => 'top_button_2', info => { text => 'Top Level Button 2', url => '/top2.cgi' }, callback => [ $obj, 'my_callback' ] }, ]; In each hash, the 'name' parameter should correspond to the $menu_item parameter passed to the generateMenu() method. This is how the module computes which menu item is selected. This is generally passed via a CGI parameter, which can be tacked onto the end of the url in your callback function. Note that this parameter must be unique among all the array entries. Otherwise, the module will not be able to decide which menu item is selected. The value of the 'info' parameter is available to your callback function via the getInfo() method called on the HTML::Menu::Hierarchical::ItemInfo object passed to the callback function. In the above example, the 'info' parameter contains text to be displayed as the menu item, and a url the user is sent to when clicking on the menu item. The 'children' parameter is a reference to another array containing configuration information for child menu items. This is where the Hierarchical part comes in. There is no limit to depth of the hierarchy (until you run out of RAM, anyway). If a 'callback' parameter is specified that callback will be used for that menu item instead of the global callback passed to new(). An 'open' parameter can be specified to force an item's children to be displayed. This can be a scalar value that indicates true or false. Or it can be a subroutine reference that returns a true or false value. It can also be an array, in which case the first element is expected to be an object, the second element the name of a method to call on that object, and the rest of the elements will be passed as arguments to the method. If an 'open_all' parameter is passed, the current item and all items under it in the hierarchy will be forced open. callback functions/methods Callback functions are passed a single parameter: an HTML::Menu::Hierarchical::ItemInfo object. See the documentation on this object for available methods. The callback function should return the HTML necessary for the corresponding menu item. METHODS new() my $menu_obj = HTML::Menu::Hierarchical->new($conf, \&callback); generateMenu($menu_item) my $html = $menu_obj->generateMenu($menu_item); $menu_item is the 'name' parameter of the selected item, typically passed as a CGI parameter. addChildConf($conf, $menu_item_name) Adds another configuration tree into the current configuration at the specified node (name of the menu item). addChildConfToChildren($conf, $menu_item_name) Like addChildConf(), except add this conf to the list of children of the parent with name $menu_item_name. If $conf is an array, each element of the array will be added to the list of children. getSelectedItemInfo($menu_item) Returns the ItemInfo object corresponding to the selected menu item. getSelectedPath($menu_item) Returns an array of InfoItem objects representing the path from the top level menu item to the selected menu item. There are also underscore_separated versions of these methods. E.g., unescapeHtml($html) becomes unescape_html($html) EXAMPLES See the scripts in the examples subdirectory for example usages. See the documentation for HTML::Menu::Hierarchical::ItemInfo for methods available via the $info_obj parameter passed to the menu_callback function below. sub menu_callback { my ($info_obj) = @_; my $info_hash = $info_obj->getInfo; my $level = $info_obj->getLevel; my $text = $$info_hash{text}; $text = ' ' if $text eq ''; my $item_arg = $info_obj->getName; # Add a cgi parameter m_i to url so we know which menu # item was chosen my $url = $info_obj->addArgsToUrl($$info_hash{url}, { m_i => $item_arg }); my $dpy_text = $info_obj->isSelected ? "<$text>" : $text; my $spacer = '  ' x $level; my $str = qq{\n}; $str .= qq{}; $str .= $spacer . $dpy_text; $str .= qq{}; $str .= qq{\n}; return $str; } BUGS Please send bug reports/feature requests to don@owensnet.com. There are currently no checks for loops in the configuration data structure passed to the module. AUTHOR Don Owens COPYRIGHT Copyright (c) 2003 Don Owens All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. VERSION 0.13 NAME HTML::Menu::Hierarchical::ItemInfo - Used by HTML::Menu::Hierarchical. Provides information about the menu item being processed. SYNOPSIS Created by HTML::Menu::Hierarchical objects. DESCRIPTION Information holder/gatherer representing one menu item. METHODS Getting back information hasChildren() Returns true if the current item has child items in the configuration. False otherwise. isSelected() Returns true if the current item is the selected one. isInSelectedPath() Returns true if the current item is in the path from the root of the hierarchy to the selected item. getSelectedItem() Returns the ItemInfo object corresponding to the selected menu item. getSelectedLevel() Returns the level in the hierarchy where the selected menu item is located. Levels start at zero. getMaxDisplayedLevel() Returns the maximum level in the hierarchy to currently be displayed. isOpen() Returns true if the current menu item is open, i.e., the current item has child items and is also in the open path. Return false otherwise. isFirstDisplayed() Returns true if the current menu item is the first one to be displayed. isLastDisplayed() Returns true if the current menu item is the last to be displayed. isFirstSiblingDisplayed() Returns true if the current menu item is the first of its siblings to be displayed, false otherwise. isLastSiblingDisplayed() Returns true if the current menu item is the last of its siblings to be displayed, false otherwise. getInfo() Returns the value of the 'info' field for the current menu item in the navigation configuration. Instead of getting the 'info' hash and then accessing a field within it, you may call a method to get that field directly. This is implemented with AUTOLOAD, so if you do something like my $text = $info_obj->getText; my $image_src = $info_obj->getImageSrc; or my $text = $info_obj->getText; my $image_src = $info_obj->get_image_src; you will be given back the corresponding values in the 'info' hash. getName() Returns the 'name' field for the current menu item in the navigation configuration. This is used to determine which menu item has been selected. getNextItem() Returns the ItemInfo object corresponding to the next displayed menu item. getPreviousItem() Returns the ItemInfo object corrsponding to the previously displayed menu item. getLevel() Returns the level in the menu hierarchy where the current menu item is located. Levels start at zero. getParent() Returns the info object for the current item's parent. Utilities my $encoded = $info->urlEncode($plain_text) URL encodes the given string. This does full url-encoding, so a space is %20, not a '+'. my $query = $info->urlEncodeVars($var_hash) Takes a hash containing key/value pairs and returns a url-encoded query string appropriate for adding to the end of a url. If a value is an array, it is assumed to be a multivalued input field and is added to the query string as such. If you want to encode the query stirng in the new style recommended by the W3C (use a semicolon as a separator in place of ampersand), pass a true value for the new_style_url parameter when creating the HTML::Menu::Hierarchical object. This will become the default in a later release. my $plain_text = $info->urlDecode($url_enc_str) Decodes the given url-encoded string. my $var_hash = $info->urlDecodeVars($url_enc_str) Decodes the url-encoded query string and returns a hash contain key/value pairs from the query string. If a field appears more than once in the query string, it's value will be returned as a reference to an array of values. my $modified_url = $info->addArgsToUrl($url, $var_hash) Takes the key/value pairs in $var_hash and tacks them onto the end of $url as a query string. my $html = $info->escapeHtml($text) Escapes the given text so that it is not interpreted as HTML. my $text = $info->unescapeHtml($html) Unescape the escaped text. There are also underscore_separated versions of these methods. E.g., unescapeHtml($html) becomes unescape_html($html) TODO hasChildrenDisplayed() - tell whether or not the current item's children will be displayed BUGS Please send bug reports/feature requests to don@owensnet.com. AUTHOR Don Owens COPYRIGHT Copyright (c) 2003 Don Owens All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. VERSION $Id: README,v 1.15 2005/06/16 15:31:06 don Exp $