Module | ActionView::Helpers::AssetTagHelper
In: | lib/action_view/helpers/asset_tag_helper.rb

Provides methods for linking a HTML page together with other assets, such as javascripts, stylesheets, and feeds.

### Methods

auto_discovery_link_tag image_path image_tag javascript_include_tag javascript_path register_javascript_include_default stylesheet_link_tag stylesheet_path

### Constants

JAVASCRIPT_DEFAULT_SOURCES | = | ['prototype', 'effects', 'dragdrop', 'controls'] unless const_defined?(:JAVASCRIPT_DEFAULT_SOURCES)

### Public Class methods

register_javascript_include_default(*sources)

Register one or more additional JavaScript files to be included when

      javascript_include_tag :defaults

is called. This method is intended to be called only from plugin initialization to register extra .js files the plugin installed in `public/javascripts`.

### Public Instance methods

auto_discovery_link_tag(type = :rss, url_options = {}, tag_options = {})

Returns a link tag that browsers and news readers can use to auto-detect a RSS or ATOM feed for this page. The `type` can either be `:rss` (default) or `:atom` and the `options` follow the url_for style of declaring a link target.

Examples:

      auto_discovery_link_tag # =>
        <link rel="alternate" type="application/rss+xml" title="RSS" href="http://www.curenthost.com/controller/action" />
      auto_discovery_link_tag(:atom) # =>
        <link rel="alternate" type="application/atom+xml" title="ATOM" href="http://www.curenthost.com/controller/action" />
      auto_discovery_link_tag(:rss, {:action => "feed"}) # =>
        <link rel="alternate" type="application/rss+xml" title="RSS" href="http://www.curenthost.com/controller/feed" />
      auto_discovery_link_tag(:rss, {:action => "feed"}, {:title => "My RSS"}) # =>
        <link rel="alternate" type="application/rss+xml" title="My RSS" href="http://www.curenthost.com/controller/feed" />

image_path(source)

Returns path to an image asset. Example:

The `src` can be supplied as a…

- full path, like "/my_images/image.gif"
- file name, like "rss.gif", that gets expanded to "/images/rss.gif"
- file name without extension, like "logo", that gets expanded to "/images/logo.png"

image_tag(source, options = {})

Returns an image tag converting the `options` into html options on the tag, but with these special cases:

- `:alt` - If no alt text is given, the file name part of the `src` is used (capitalized and without the extension)
- `:size` - Supplied as "XxY", so "30x45" becomes width="30" and height="45"

The `src` can be supplied as a…

- full path, like "/my_images/image.gif"
- file name, like "rss.gif", that gets expanded to "/images/rss.gif"
- file name without extension, like "logo", that gets expanded to "/images/logo.png"

javascript_include_tag(*sources)

Returns a script include tag per source given as argument. Examples:

      javascript_include_tag "xmlhr" # =>
        <script type="text/javascript" src="/javascripts/xmlhr.js"></script>

      javascript_include_tag "common.javascript", "/elsewhere/cools" # =>
        <script type="text/javascript" src="/javascripts/common.javascript"></script>
        <script type="text/javascript" src="/elsewhere/cools.js"></script>

      javascript_include_tag :defaults # =>
        <script type="text/javascript" src="/javascripts/prototype.js"></script>
        <script type="text/javascript" src="/javascripts/effects.js"></script>
        ...
        <script type="text/javascript" src="/javascripts/application.js"></script> *see below

If there’s an `application.js` file in your `public/javascripts` directory, `javascript_include_tag :defaults` will automatically include it. This file facilitates the inclusion of small snippets of JavaScript code, along the lines of `controllers/application.rb` and `helpers/application_helper.rb`.

javascript_path(source)

Returns path to a javascript asset. Example:

      javascript_path "xmlhr" # => /javascripts/xmlhr.js

stylesheet_link_tag(*sources)

Returns a css link tag per source given as argument. Examples:

      stylesheet_link_tag "style" # =>
        <link href="/stylesheets/style.css" media="screen" rel="Stylesheet" type="text/css" />

      stylesheet_link_tag "style", :media => "all" # =>
        <link href="/stylesheets/style.css" media="all" rel="Stylesheet" type="text/css" />

      stylesheet_link_tag "random.styles", "/css/stylish" # =>
        <link href="/stylesheets/random.styles" media="screen" rel="Stylesheet" type="text/css" />
        <link href="/css/stylish.css" media="screen" rel="Stylesheet" type="text/css" />

stylesheet_path(source)

Returns path to a stylesheet asset. Example:

      stylesheet_path "style" # => /stylesheets/style.css

[Validate]