ruby on rails - (How) Can I use a form object for the edit/update routines? -

couldn't resist try out relaunched railsforum , crossposted question here.

i have following form object (in rails 4)

class stationform     include virtus      include activemodel::model     # think unnecessary     #   extend activemodel::naming     #   include activemodel::conversion     #   include activemodel::validations   # station     attr_reader :station      attribute :station_name, string     attribute :station_description, string  # address     attr_reader :address      attribute :address_url, string     attribute :address_priority, integer     attribute :address_is_active, boolean      def persisted?         false     end      def save         if valid?             persist             true         else             false         end     end  private      def persist         @station = station.create(name: station_name, description: station_description)         @address = @station.addresses.create(url: address_url, priority: address_priority, is_active: address_is_active)     end end 

i can use form object in new/create methods

class stationscontroller < applicationcontroller     def new         @station_form = stationform.new     end      def create         @station_form = stationform.new(station_form_params)         @station_form.save          redirect_to station_path(@station)     end  private      def station_form_params         params.require(:station_form).permit(:station_name, :station_description, :address_url, :address_priority, :address_is_active)     end end 

however, don't succeed use edit/update procedures...

is possible use form object edit/update , if yes, how done?

you have use "initialize" method in stationform object use editing. if pass id, assume, object exist , there can treat persisted object. add "update" method update attributes of object.

class stationform include virtus.model  include activemodel::model # think unnecessary #   extend activemodel::naming #   include activemodel::conversion #   include activemodel::validations   attr_reader :station  attribute :station_name, string attribute :station_description, string  attr_reader :address  attribute :address_url, string attribute :address_priority, integer attribute :address_is_active, boolean  def initialize(attr = {})  if !attr["id"].nil?     @station = station.find(attr["id"])     @address = @station.addresses.first     self[:station_name] = attr[:station_name].nil? ? @station.name : attr[:station_name]     self[:station_description] = attr[:station_description].nil? ? @station.description : attr[:station_description]     self[:address_url] =  attr[:address_url].nil? ? @address.url : attr[:address_url]     self[:address_priority] = attr[:address_priority].nil? ? @address.priority : attr[:address_priority]     self[:address_is_active] = attr[:address_is_active].nil? ? @address.is_active : attr[:address_is_active]  else    super(attr)  end end  def persisted?     @station.nil? ? false : @station.persisted? end  def id    @station.nil? ? nil : @station.id end  def save     if valid?         persist         true     else         false     end end  def update     if valid?         update_form         true     else         false     end end  private   def persist     @station = station.create(name: station_name, description: station_description)     @address = @station.addresses.create(url: address_url, priority: address_priority, is_active: address_is_active)  end   def update_form     @station.update_attributes(         :name => self[:station_name],         :description => self[:station_description]         )     @address.update_attributes(         :url => self[:address_url],         :priority => self[:address_priority],         :is_active=> self[:address_is_active]         )  end end 

and controller like

def new  @station = stationform.new end  def edit  @station = stationform.new("id" => params[:id]) end  def create   @station = stationform.new(station_params)   respond_to |format|    if @station.save      format.html { redirect_to  stations_path, notice: 'station  created.' }      format.json { render :show, status: :created, location: @station }    else      format.html { render :new }      format.json { render json: @station.errors, status: :unprocessable_entity  }     end  end end  def update  @station = stationform.new(station_params.merge("id" => params[:id]))  respond_to |format|    if @station.update      format.html { redirect_to stations_path, notice: 'station  updated.' }      format.json { render :show, status: :ok, location: @station }    else      format.html { render :edit }      format.json { render json: @station.errors, status: :unprocessable_entity  }    end  end end 

use "persisted" , "id" method stationform in _form.html.erb

    <%= form_for(@station, :url => @station.persisted? ? station_path(@station.id) : stations_path, :method => @station.persisted? ? "put": "post") |f| %>   <% if @station.errors.any? %>     <div id="error_explanation">       <h2><%= pluralize(@station.errors.count, "error") %> prohibited station being saved:</h2>        <ul>       <% @station.errors.full_messages.each |message| %>         <li><%= message %></li>       <% end %>       </ul>     </div>   <% end %>    <div class="field">     <%= f.label :station_name %><br>     <%= f.text_field :station_name %>   </div>   <div class="field">     <%= f.label :station_description %><br>     <%= f.text_field :station_description %>   </div>   <div class="field">     <%= f.label :address_url%><br>     <%= f.text_field :address_url %>   </div>   <div class="field">     <%= f.label :address_priority%><br>     <%= f.text_field :address_priority%>   </div>   <div class="field">     <%= f.label :address_is_active %><br>     <%= f.text_field :address_is_active %>   </div>    <div class="actions">     <%= f.submit %>   </div> <% end %>