Class: ActionView::Component::Base

Inherits:
Base
  • Object
show all
Includes:
Previewable, ActiveModel::Validations, ActiveSupport::Configurable
Defined in:
lib/action_view/component/base.rb

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initializeBase

Returns a new instance of Base.



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# File 'lib/action_view/component/base.rb', line 69

def initialize(*); end

Class Method Details

.call_method_name(variant) ⇒ Object



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# File 'lib/action_view/component/base.rb', line 135

def call_method_name(variant)
  if variant.present? && variants.include?(variant)
    "call_#{variant}"
  else
    "call"
  end
end

.compile(validate: false) ⇒ Object

Compile templates to instance methods, assuming they haven’t been compiled already. We could in theory do this on app boot, at least in production environments. Right now this just compiles the first time the component is rendered.



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# File 'lib/action_view/component/base.rb', line 170

def compile(validate: false)
  return if compiled?

  if template_errors.present?
    raise ActionView::Component::TemplateError.new(template_errors) if validate
    return false
  end

  templates.each do |template|
    class_eval "      def \#{call_method_name(template[:variant])}\n        @output_buffer = ActionView::OutputBuffer.new\n        \#{compiled_template(template[:path])}\n      end\n    RUBY\n  end\n\n  @compiled = true\nend\n", __FILE__, __LINE__ + 1

.compile!Object



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# File 'lib/action_view/component/base.rb', line 163

def compile!
  compile(validate: true)
end

.compiled?Boolean

Returns:

  • (Boolean)


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# File 'lib/action_view/component/base.rb', line 159

def compiled?
  @compiled && ActionView::Base.cache_template_loading
end

.identifierObject



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# File 'lib/action_view/component/base.rb', line 199

def identifier
  source_location
end

.inherited(child) ⇒ Object



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# File 'lib/action_view/component/base.rb', line 129

def inherited(child)
  child.include Rails.application.routes.url_helpers unless child < Rails.application.routes.url_helpers

  super
end

.source_locationObject



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# File 'lib/action_view/component/base.rb', line 143

def source_location
  @source_location ||=
      begin
        # Require #initialize to be defined so that we can use
        # method#source_location to look up the file name
        # of the component.
        #
        # If we were able to only support Ruby 2.7+,
        # We could just use Module#const_source_location,
        # rendering this unnecessary.
        #
        initialize_method = instance_method(:initialize)
        initialize_method.source_location[0] if initialize_method.owner == self
      end
end

.typeObject

we’ll eventually want to update this to support other types



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# File 'lib/action_view/component/base.rb', line 195

def type
  "text/html"
end

.variantsObject



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# File 'lib/action_view/component/base.rb', line 190

def variants
  templates.map { |template| template[:variant] }
end

.with_content_areas(*areas) ⇒ Object



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# File 'lib/action_view/component/base.rb', line 203

def with_content_areas(*areas)
  if areas.include?(:content)
    raise ArgumentError.new ":content is a reserved content area name. Please use another name, such as ':body'"
  end
  attr_reader *areas
  self.content_areas = areas
end

Instance Method Details

#controllerObject



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# File 'lib/action_view/component/base.rb', line 79

def controller
  @controller ||= view_context.controller
end

#formatObject

:nodoc:



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# File 'lib/action_view/component/base.rb', line 97

def format # :nodoc:
  @variant
end

#helpersObject

Provides a proxy to access helper methods through



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# File 'lib/action_view/component/base.rb', line 84

def helpers
  @helpers ||= view_context
end

#render(options = {}, args = {}, &block) ⇒ Object



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# File 'lib/action_view/component/base.rb', line 71

def render(options = {}, args = {}, &block)
  if options.is_a?(String) || (options.is_a?(Hash) && options.has_key?(:partial))
    view_context.render(options, args, &block)
  else
    super
  end
end

#render?Boolean

Returns:

  • (Boolean)


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# File 'lib/action_view/component/base.rb', line 65

def render?
  true
end

#render_in(view_context, *args, &block) ⇒ Object

Entrypoint for rendering components. Called by ActionView::Base#render.

view_context: ActionView context from calling view args(hash): params to be passed to component being rendered block: optional block to be captured within the view context

returns HTML that has been escaped by the respective template handler

Example subclass:

app/components/my_component.rb: class MyComponent < ActionView::Component::Base

def initialize(title:)
  @title = title
end

end

app/components/my_component.html.erb <span title=“<%= @title %>”>Hello, <%= content %>!</span>

In use: <%= render MyComponent, title: “greeting” do %>world<% end %> returns: <span title=“greeting”>Hello, world!</span>



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# File 'lib/action_view/component/base.rb', line 42

def render_in(view_context, *args, &block)
  self.class.compile!
  @view_context = view_context
  @view_renderer ||= view_context.view_renderer
  @lookup_context ||= view_context.lookup_context
  @view_flow ||= view_context.view_flow
  @virtual_path ||= virtual_path
  @variant = @lookup_context.variants.first

  return "" unless render?

  old_current_template = @current_template
  @current_template = self

  @content = view_context.capture(self, &block) if block_given?

  validate!

  send(self.class.call_method_name(@variant))
ensure
  @current_template = old_current_template
end

#view_cache_dependenciesObject



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# File 'lib/action_view/component/base.rb', line 93

def view_cache_dependencies
  []
end

#virtual_pathObject

Removes the first part of the path and the extension.



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# File 'lib/action_view/component/base.rb', line 89

def virtual_path
  self.class.source_location.gsub(%r{(.*app/components)|(\.rb)}, "")
end

#with(area, content = nil, &block) ⇒ Object



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# File 'lib/action_view/component/base.rb', line 101

def with(area, content = nil, &block)
  unless content_areas.include?(area)
    raise ArgumentError.new "Unknown content_area '#{area}' - expected one of '#{content_areas}'"
  end

  if block_given?
    content = view_context.capture(&block)
  end

  instance_variable_set("@#{area}".to_sym, content)
  nil
end