NAME
    HTML::Prototype - Generate HTML and Javascript for the Prototype library

SYNOPSIS
        use HTML::Prototype;

        my $prototype = HTML::Prototype->new;
        print $prototype->auto_complete_field(...);
        print $prototype->auto_complete_result(...);
        print $prototype->auto_complete_stylesheet(...);
        print $prototype->content_tag(...);
        print $prototype->define_javascript_functions;
        print $prototype->draggable_element(...);
        print $prototype->drop_receiving_element(...);
        print $prototype->evaluate_remote_response(...);
        print $prototype->form_remote_tag(...);
        print $prototype->javascript_tag(...);
        print $prototype->link_to_function(...);
        print $prototype->link_to_remote(...);
        print $prototype->observe_field(...);
        print $prototype->observe_form(...);
        print $prototype->periodically_call_remote(...);
        print $prototype->sortable_element(...);
        print $prototype->submit_to_remote(...);
        print $prototype->tag(...);
        print $ptototype->update_element_function(...);
        print $prototype->visual_effect(...);

DESCRIPTION
    The module contains some code generators for Prototype, the famous
    JavaScript OO library and the script.aculous extensions.

    The Prototype library (http://prototype.conio.net/) is designed to make
    AJAX easy. Catalyst::Plugin::Prototype makes it easy to connect to the
    Prototype library.

    This is mostly a port of the Ruby on Rails helper tags for JavaScript
    for use in Catalyst.

  METHODS
    $prototype->auto_complete_field( $field_id, \%options )
        Adds Ajax autocomplete functionality to the text input field with
        the DOM ID specified by "field_id".

        This function expects that the called action returns a HTML <ul>
        list, or nothing if no entries should be displayed for
        autocompletion.

        Required options are:

        "url": Specifies the URL to be used in the AJAX call.

        Addtional options are:

        "update": Specifies the DOM ID of the element whose innerHTML should
        be updated with the autocomplete entries returned by the Ajax
        request. Defaults to field_id + '_auto_complete'.

        "with": A Javascript expression specifying the parameters for the
        XMLHttpRequest. This defaults to 'value', which in the evaluated
        context refers to the new field value.

        "indicator": Specifies the DOM ID of an elment which will be
        displayed while autocomplete is running.

    $prototype->auto_complete_result(\@items)
        Returns a list, to communcate with the Autocompleter.

        Here's an example for Catalyst:

            sub autocomplete : Global {
                my ( $self, $c ) = @_;
                my @items = qw/foo bar baz/;
                $c->res->body( $c->prototype->auto_complete_result(\@items) );
            }

    $prototype->auto_complete_stylesheet
        Returns the auto_complete stylesheet.

    $prototype->content_tag( $name, $content, \%html_options )
        Returns a block with opening tag, content, and ending tag. Useful
        for autogenerating tags like <a
        href="http://catalyst.perl.org"Catalyst Homepage</a>>. The first
        parameter is the tag name, i.e. 'a' or 'img'.

    $prototype->define_javascript_functions
        Returns the library of JavaScript functions and objects, in a script
        block.

        Notes for Catalyst users:

        You can use "script/myapp_create.pl Prototype" to generate a static
        JavaScript file which then can be included via remote "script" tag.

    $prototype->draggable_element( $element_id, \%options )
        Makes the element with the DOM ID specified by "element_id"
        draggable.

        Example:

            $prototype->draggable_element( 'my_image', { revert => 'true' } );

        The available options are:

        handle
            Default: none. Sets whether the element should only be draggable
            by an embedded handle. The value is a string referencing a CSS
            class. The first child/grandchild/etc. element found within the
            element that has this CSS class will be used as the handle.

        revert
            Default: false. If set to true, the element returns to its
            original position when the drags ends.

        constraint
            Default: none. If set to 'horizontal' or 'vertical' the drag
            will be constrained to take place only horizontally or
            vertically.

        change
            Javascript callback function called whenever the Draggable is
            moved by dragging. It should be a string whose contents is a
            valid JavaScript function definition. The called function gets
            the Draggable instance as its parameter. It might look something
            like this:

                'function (element) { // do something with dragged element }'

        See http://script.aculo.us for more documentation.

    $prototype->drop_receiving_element( $element_id, \%options )
        Makes the element with the DOM ID specified by "element_id" receive
        dropped draggable elements (created by draggable_element).

        And make an AJAX call.

        By default, the action called gets the DOM ID of the element as
        parameter.

        Example: $prototype->drop_receiving_element( 'my_cart', { url =>
        'http://foo.bar/add' } );

        Required options are:

        url The URL for the AJAX call.

        Additional options are:

        accept
            Default: none. Set accept to a string or an array of strings
            describing CSS classes. The Droppable will only accept
            Draggables that have one or more of these CSS classes.

        containment
            Default: none. The droppable will only accept the Draggable if
            the Draggable is contained in the given elements (or element
            ids). Can be a single element or an array of elements. This is
            option is used by Sortables to control Drag-and-Drop between
            Sortables.

        overlap
            Default: none. If set to 'horizontal' or 'vertical' the
            droppable will only react to a Draggable if it overlaps by more
            than 50% in the given direction. Used by Sortables.

            Additionally, the following JavaScript callback functions can be
            used in the option parameter:

        onHover
            Javascript function called whenever a Draggable is moved over
            the Droppable and the Droppable is affected (would accept it).
            The callback gets three parameters: the Draggable, the Droppable
            element, and the percentage of overlapping as defined by the
            overlap option. Used by Sortables. The function might look
            something like this:

                'function (draggable, droppable, pcnt) { // do something }'

        See http://script.aculo.us for more documentation.

    $prototype->evaluate_remote_response
        Returns 'eval(request.responseText)' which is the Javascript
        function that form_remote_tag can call in :complete to evaluate a
        multiple update return document using update_element_function calls.

    $prototype->form_remote_tag(\%options)
        Returns a form tag that will submit in the background using
        XMLHttpRequest, instead of the regular reloading POST arrangement.

        Even though it is using JavaScript to serialize the form elements,
        the form submission will work just like a regular submission as
        viewed by the receiving side.

        The options for specifying the target with "url" and defining
        callbacks are the same as "link_to_remote".

    $prototype->javascript_tag( $content, \%html_options )
        Returns a javascript block with opening tag, content and ending tag.

    $prototype->link_to_function( $name, $function, \%html_options )
        Returns a link that will trigger a JavaScript function using the
        onClick handler and return false after the fact.

        Examples:

            $prototype->link_to_function( "Greeting", "alert('Hello world!') )
            $prototype->link_to_function( '<img src="really.png"/>', 'do_delete()' )

    $prototype->link_to_remote( $content, \%options, \%html_options )
        Returns a link to a remote action defined by options "url" that's
        called in the background using XMLHttpRequest.

        The result of that request can then be inserted into a DOM object
        whose id can be specified with options->{update}.

        Examples:

            $prototype->link_to_remote( 'Delete', {
                update => 'posts',
                url    => 'http://localhost/posts/'
            } )

            $prototype->link_to_remote( '<img src="refresh.png"/>', {
                update => 'emails',
                url    => 'http://localhost/refresh/'
            } )

        By default, these remote requests are processed asynchronously,
        during which various callbacks can be triggered (e.g. for progress
        indicators and the like).

        Example:

            $prototype->link_to_remote( 'count', {
                url => 'http://localhost/count/',
                complete => 'doStuff(request)'
            } )

        The callbacks that may be specified are:

        "loading": Called when the remote document is being loaded with data
        by the browser.

        "loaded": Called when the browser has finished loading the remote
        document.

        "interactive": Called when the user can interact with the remote
        document, even though it has not finished loading.

        "complete": Called when the XMLHttpRequest is complete.

        If you do need synchronous processing (this will block the browser
        while the request is happening), you can specify $options->{type} =
        'synchronous'.

        You can customize further browser side call logic by passing in
        Javascript code snippets via some optional parameters. In their
        order of use these are:

        "confirm": Adds confirmation dialog.

        "condition": Perform remote request conditionally by this
        expression. Use this to describe browser-side conditions when
        request should not be initiated.

        "before": Called before request is initiated.

        "after": Called immediately after request was initiated and before
        "loading".

    $prototype->observe_field( $id, \%options)
        Observes the field with the DOM ID specified by $id and makes an
        Ajax when its contents have changed.

        Required options are:

        "frequency": The frequency (in seconds) at which changes to this
        field will be detected.

        "url": url to be called when field content has changed.

        Additional options are:

        "update": Specifies the DOM ID of the element whose innerHTML should
        be updated with the XMLHttpRequest response text.

        "with": A JavaScript expression specifying the parameters for the
        XMLHttpRequest. This defaults to value, which in the evaluated
        context refers to the new field value.

        Additionally, you may specify any of the options documented in
        "link_to_remote".

        Example TT2 template in Catalyst:

            [% c.prototype.define_javascript_functions %]
            <h1>[% page.title %]</h1>
            <div id="view"></div>
            <textarea id="editor" rows="24" cols="80">[% page.body %]</textarea>
            [% url = base _ 'edit/' _ page.title %]
            [% c.prototype.observe_field( 'editor', {
                url    => url,
                with   => "'body='+value",
                update => 'view'
            } ) %]

    $prototype->observe_form( $id, \%options )
        Like "observe_field", but operates on an entire form identified by
        the DOM ID $id.

        Options are the same as "observe_field", except the default value of
        the "with" option evaluates to the serialized (request string) value
        of the form.

    $prototype->periodically_call_remote( \%options )
        Periodically calls the specified url $options->{url} every
        $options->{frequency} seconds (default is 10).

        Usually used to update a specified div $options->{update} with the
        results of the remote call.

        The options for specifying the target with "url" and defining
        callbacks is the same as "link_to_remote".

    $prototype->sortable_element( $element_id, \%options )
        Makes the element with the DOM ID specified by +element_id+ sortable
        by drag-and-drop and make an Ajax call whenever the sort order has
        changed. By default, the action called gets the serialized sortable
        element as parameters.

        Example: $ptototype->sortable_element( 'my_list', { url =>
        'http://foo.bar/baz' } );

        In the example, the action gets a "my_list" array parameter
        containing the values of the ids of elements the sortable consists
        of, in the current order.

        You can change the behaviour with various options, see
        http://script.aculo.us for more documentation.

    $prototype->submit_to_remote( $name, $value, \%options )
        Returns a button input tag that will submit a form using
        XMLHttpRequest in the background instead of a typical reloading via
        POST.

        "options" argument is the same as in "form_remote_tag"

    $prototype->tag( $name, \%options, $starttag );
        Returns a opening tag.

    $prototype->update_element_function( $element_id, \%options, \&code )
        Returns a Javascript function (or expression) that'll update a DOM
        element according to the options passed.

        "content": The content to use for updating. Can be left out if using
        block, see example.

        "action": Valid options are "update" (assumed by default), :empty,
        :remove

        "position": If the :action is :update, you can optionally specify
        one of the following positions: :before, :top, :bottom, :after.

        Example: $prototype->javascript_tag(
        $prototype->update_element_function( 'products', { position =>
        'bottom', content => '<p>New product!</p>' ) );

        This method can also be used in combination with remote method call
        where the result is evaluated afterwards to cause multiple updates
        on a page.

        Example: # View $prototype->form_remote_tag( { url => {
        "http://foo.bar/buy" }, complete =>
        $prototype->evaluate_remote_response } );

            # Returning view
            $prototype->update_element_function( 'cart', {
                action   => 'update',
                position => 'bottom', 
                content  => "<p>New Product: $product_name</p>"
            } );
            $prototype->update_element_function( 'status',
                { binding => "You've bought a new product!" } );

    $prototype->visual_effect( $name, $element_id, \%js_options )
        Returns a JavaScript snippet to be used on the Ajax callbacks for
        starting visual effects.

            $prototype->link_to_remote( 'Reload', {
                update   => 'posts',
                url      => 'http://foo.bar/baz',
                complete => $prototype->visual_effect( 'highlight', 'posts', {
                    duration => '0.5'
                } )
            } );

SEE ALSO
    Catalyst::Plugin::Prototype, Catalyst. <http://prototype.conio.net/>

AUTHOR
    Sebastian Riedel, "sri@oook.de" Marcus Ramberg, "mramberg@cpan.org"

    Built around Prototype by Sam Stephenson. Much code is ported from Ruby
    on Rails javascript helpers.

THANK YOU
    Drew Taylor, Leon Brocard, Andreas Marienborg

LICENSE
    This library is free software. You can redistribute it and/or modify it
    under the same terms as perl itself.