Module: Cell::ClassMethods

Defined in:
lib/cell.rb

Instance Method Summary collapse

Instance Method Details

#build(&block) ⇒ Object

Adds a builder to the cell class. Builders are used in #render_cell to find out the concrete class for rendering. This is helpful if you frequently want to render subclasses according to different circumstances (e.g. login situations) and you don’t want to place these deciders in your view code.

Passes the opts hash from #render_cell into the block. The block is executed in controller context. Multiple build blocks are ORed, if no builder matches the building cell is used.

Example:

Consider two different user box cells in your app.

class AuthorizedUserBox < UserInfoBox
end

class AdminUserBox < UserInfoBox
end

Now you don’t want to have deciders all over your views - use a declarative builder.

UserInfoBox.build do |opts|
  AuthorizedUserBox if user_signed_in?
  AdminUserBox if admin_signed_in?
end

In your view #render_cell will instantiate the right cell for you now.



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# File 'lib/cell.rb', line 58

def build(&block)
  builders << block
end

#build_class_for(controller, target_class, *args) ⇒ Object 



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# File 'lib/cell.rb', line 62

def build_class_for(controller, target_class, *args)
  target_class.builders.each do |blk|
    res = controller.instance_exec(*args, &blk) and return res
  end
  target_class
end

#builders ⇒ Object 



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# File 'lib/cell.rb', line 69

def builders
  @builders ||= []
end

#class_from_cell_name(cell_name) ⇒ Object

The cell class constant for cell_name.



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# File 'lib/cell.rb', line 74

def class_from_cell_name(cell_name)
  "#{cell_name}_cell".classify.constantize
end

#create_cell_for(controller, name, *args) ⇒ Object

Creates a cell instance. Note that this method calls builders which were attached to the class with Cell::Base.build - this might lead to a different cell being returned.



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# File 'lib/cell.rb', line 27

def create_cell_for(controller, name, *args)
  build_class_for(controller, class_from_cell_name(name), *args).
  new(controller, *args)
end

#render_cell_for(controller, name, state, *args) {|cell| ... } ⇒ Object

Yields:

  • (cell) 


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# File 'lib/cell.rb', line 17

def render_cell_for(controller, name, state, *args)
  cell = create_cell_for(controller, name, *args)  # DISCUSS: we always save options.
  yield cell if block_given?
  
  return cell.render_state(state, *args) if cell.state_accepts_args?(state)
  cell.render_state(state)  # backward-compat.
end

#setup_view_paths! ⇒ Object

Called in Railtie at initialization time.



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# File 'lib/cell.rb', line 13

def setup_view_paths!
  self.view_paths = self::DEFAULT_VIEW_PATHS
end