Module: Alchemy::ElementsHelper

Includes:
ElementsBlockHelper, UrlHelper
Included in:
PagesHelper
Defined in:
app/helpers/alchemy/elements_helper.rb

Overview

This helpers are useful to render elements from pages.

The most important helper for frontend developers is the #render_elements helper.

Instance Method Summary collapse

Methods included from ElementsBlockHelper

#element_view_for

Methods included from UrlHelper

#download_alchemy_attachment_path, #download_alchemy_attachment_url, #full_url_for_element, #show_alchemy_page_path, #show_alchemy_page_url, #show_page_path_params

Instance Method Details

#element_dom_id(element) ⇒ Object

Returns a string for the id attribute of a html element for the given element



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# File 'app/helpers/alchemy/elements_helper.rb', line 174

def element_dom_id(element)
  return "" if element.nil?

  "#{element.name}_#{element.id}".html_safe
end

#element_preview_code(element) ⇒ Object

Renders the HTML tag attributes required for preview mode.



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# File 'app/helpers/alchemy/elements_helper.rb', line 181

def element_preview_code(element)
  tag_builder.tag_options(element_preview_code_attributes(element))
end

#element_preview_code_attributes(element) ⇒ Object

Returns a hash containing the HTML tag attributes required for preview mode.



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# File 'app/helpers/alchemy/elements_helper.rb', line 186

def element_preview_code_attributes(element)
  return {} unless element.present? && @preview_mode && element.page == @page

  { "data-alchemy-element" => element.id }
end

#element_tags(element, options = {}) ⇒ String

Returns the element’s tags information as a string. Parameters and options are equivalent to #element_tags_attributes.

Returns:

  • (String) —

    HTML tag attributes containing the element’s tag information.

See Also:



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# File 'app/helpers/alchemy/elements_helper.rb', line 200

def element_tags(element, options = {})
  tag_builder.tag_options(element_tags_attributes(element, options))
end

#element_tags_attributes(element, options = {}) ⇒ Hash

Returns the element’s tags information as an attribute hash.

Parameters:

Options Hash (options):

  • :formatter (Proc) — default: 'lambda { |tags| tags.join(' ') }' —

    Lambda converting array of tags to a string.

Returns:

  • (Hash) —

    HTML tag attributes containing the element’s tag information.



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# File 'app/helpers/alchemy/elements_helper.rb', line 215

def element_tags_attributes(element, options = {})
  options = {
    formatter: lambda { |tags| tags.join(" ") },
  }.merge(options)

  return {} if !element.taggable? || element.tag_list.blank?

  { "data-element-tags" => options[:formatter].call(element.tag_list) }
end

#render_element(element, options = {}, counter = 1) ⇒ Object

Note:

If the view partial is not found alchemy/elements/_view_not_found.html.erb gets rendered.

This helper renders a Alchemy::Element view partial.

A element view partial is the html snippet presented to the website visitor.

The partial is located in app/views/alchemy/elements.

View partial naming

The partial has to be named after the name of the element as defined in the elements.yml file.

Example

Given a headline element

# elements.yml
- name: headline
  contents:
  - name: text
    type: EssenceText

Then your element view partial has to be named like:

app/views/alchemy/elements/_headline.html.{erb|haml|slim}

Element partials generator

You can use this handy generator to let Alchemy generate the partials for you:

$ rails generate alchemy:elements --skip

Usage

<%= render_element(Alchemy::Element.available.named(:headline).first) %>

Parameters:

  • element (Alchemy::Element) —

    The element you want to render the view for

  • options (Hash) (defaults to: {}) —

    Additional options

  • counter (Number) (defaults to: 1) —

    a counter



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# File 'app/helpers/alchemy/elements_helper.rb', line 151

def render_element(element, options = {}, counter = 1)
  if element.nil?
    warning("Element is nil")
    render "alchemy/elements/view_not_found", {name: "nil"}
    return
  end

  element.store_page(@page)

  render element, {
    element: element,
    counter: counter,
    options: options,
  }.merge(options.delete(:locals) || {})
rescue ActionView::MissingTemplate => e
  warning(%(
    Element view partial not found for #{element.name}.\n
    #{e}
  ))
  render "alchemy/elements/view_not_found", name: element.name
end

#render_elements(options = {}) ⇒ Object

Renders elements from given page

Examples:

Render only certain elements:

<header>
  <%= render_elements only: ['header', 'claim'] %>
</header>
<section id="content">
  <%= render_elements except: ['header', 'claim'] %>
</section>

Render elements from global page:

<footer>
  <%= render_elements from_page: 'footer' %>
</footer>

Fallback to elements from global page:

You can use the fallback option as an override for elements that are stored on another page. So you can take elements from a global page and only if the user adds an element on current page the local one gets rendered.

  1. You have to pass the the name of the element the fallback is for as for key.

  2. You have to pass a page_layout name or Page from where the fallback elements is taken from as from key.

  3. You can pass the name of element to fallback with as with key. This is optional (the element name from the for key is taken as default).

<%= render_elements(fallback: {
  for: 'contact_teaser',
  from: 'sidebar',
  with: 'contact_teaser'
}) %>

Custom elements finder:

Having a custom element finder class:

class MyCustomNewsArchive
  def elements(page:)
    news_page.elements.named('news').order(created_at: :desc)
  end

  private

  def news_page
    Alchemy::Page.where(page_layout: 'news-archive')
  end
end

In your view:

<div class="news-archive">
  <%= render_elements finder: MyCustomNewsArchive.new %>
</div>

Parameters:

  • options (Hash) (defaults to: {}) —

    a customizable set of options

Options Hash (options):

  • :from_page (Alchemy::Page|String) — default: @page —

    The page the elements are rendered from. You can pass a page_layout String or a Page object.

  • :only (Array<String>|String) —

    A list of element names only to be rendered.

  • :except (Array<String>|String) —

    A list of element names not to be rendered.

  • :count (Number) —

    The amount of elements to be rendered (begins with first element found)

  • :offset (Number) —

    The offset to begin loading elements from

  • :fallback (Hash) —

    Define elements that are rendered from another page.

  • :random (Boolean) — default: false —

    Randomize the output of elements

  • :reverse (Boolean) — default: false —

    Reverse the rendering order

  • :separator (String) —

    A string that will be used to join the element partials.

  • :finder (Class) — default: Alchemy::ElementsFinder —

    A class instance that will return elements that get rendered. Use this for your custom element loading logic in views.



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# File 'app/helpers/alchemy/elements_helper.rb', line 91

def render_elements(options = {})
  options = {
    from_page: @page,
    render_format: "html",
  }.update(options)

  finder = options[:finder] || Alchemy::ElementsFinder.new(options)
  elements = finder.elements(page: options[:from_page])

  buff = []
  elements.each_with_index do |element, i|
    buff << render_element(element, options, i + 1)
  end
  buff.join(options[:separator]).html_safe
end