cedar-component

Cedar

Cedar allows you to render view_component without a sidecar template. It leverages ActiveAdmin's arbre to provide a pure ruby DSL for creating markup. In addition Cedar provides convenience methods for rendering components and component collections.

Installation

Add this line to your application's Gemfile:

gem 'cedar-component'

And then execute:

$ bundle install

Or install it yourself as:

$ gem install cedar

Usage

To use Cedar, you need to extend your components with Cedar::Component. The most straight forward way to do this is right in your base ApplicationComponent class.

class ApplicationComponent < ViewComponent::Base
  extend Cedar::Component
end

Cedar provides 3 key pieces of functionality:

Rendering an arbre tree

render is now available to you as a class level method, which renders the contained arbre tree.

class FoobarComponent < ApplicationComponent
  render do
    div do
      para "Wow this is kind of neat"
    end
  end
end

Rendering components

We provide a shortcut for rendering components themselves. If you have a component called MyCoolButtonComponent, you can render this by simply calling my_cool_button within your arbre tree.

class FoobarComponent < ApplicationComponent
  class MyCoolButtonComponent < ApplicationComponent
    def initialize(label:)
      @label = label  
    end

    render { button_tag "Click me!", class: "btn btn-primary" } 
  end

  render do
    div do
      para "We're going to render our cool button below"
      my_cool_button label: "Click me!"
    end
  end
end

Rendering collections

Suffixing your component tag with _collection will render a collection of your components.

class FoobarComponent < ApplicationComponent
  class MyCoolButtonComponent < ApplicationComponent
    with_collection_param :label
    def initialize(label:)
      @label = label
    end
    render { button_tag "Click me!", class: "btn btn-primary" } 
  end

  render do
    my_cool_button_collection %w[One Two Three Four]
  end
end

ActionView helpers

If you need to access the underlying rails helpers instead of the arbre helpers, use the helpers object. For example, if you were making a compatible wrapper around label:

class LabelComponenent < ApplicationComponent
  def initialize(object_name, method, text = nil, options = {})
    @object_name = object_name
    @method = method
    @text = text
    @options = options
    @options[:class] ||= "label"
  end

  render do
    helpers.label @object_name, @method, @text, @options
  end
end