mongoid dynamic_fields demo base on bbtangcms(recommend_other depend on other_column)

_form.html.erb

<%= simple_form_for(@recommend_recommend_other, :html => {id: "recommend_recommend_other"}) do |f| %>
  <%= f.error_notification %>

  <div class="form-inputs">
    <%= f.input :_id, as: :hidden %>
    <%= f.input :recommend_other_type, as: :select, collection: Recommend::OtherColumn.all.map(&:recommend_type) %>
    <%# f.input :created_at %>
    <%# f.input :updated_at %>
    <% dynamic_feilds = @recommend_recommend_other.dynamic_attribute_names %>
    <% if dynamic_feilds.present? %>
      <% dynamic_feilds.each do |dynamic_feild|%>
        <%= f.input dynamic_feild, :label => "#{@recommend_recommend_other.dynamic_attribute_human(dynamic_feild)}"  %>
      <% end %>
    <% end %>
  </div>

  <div class="form-actions">
    <%= f.button :submit, :class => 'btn-primary', :disable_with => 'loading...' %>
    <%= link_to t('.cancel', :default => t("helpers.links.cancel")),
                recommend_recommend_others_path, :class => 'btn' %>
  </div>
<% end %>

other_column.rb

# encoding: utf-8
class Recommend::OtherColumn
  include Mongoid::Document
  #include Mongoid::Timestamps::Created
  include Mongoid::Timestamps

  field :recommend_type, type: String
  #field :other_column_hash, type: Array#[human_name , colmun_name]
  field :human_names, type: Array #[human_name1 , human_name2, human_name3]
  field :column_names, type: Array #[colmun_name1 , colmun_name2, colmun_name3]
  before_validation :set_array

  validates_uniqueness_of :recommend_type


  def set_array
    self.human_names = convert_array(self.human_names)
    self.column_names = convert_array(self.column_names)
  end

  def convert_array(str=nil)
    if str.present?
     str = str.to_s.split(/，|,|;|；|\ +|\||\r\n/).collect {|t| t if t.present?}.uniq.compact
    else
      []
    end
  end

=begin
  def dynamic_attributes
    self.attributes.delete_if { |attribute|
      self.fields.keys.member? attribute
    }
  end
=end
end

recommend_other.rb

# encoding: utf-8
class Recommend::RecommendOther
  include Mongoid::Document
  #include Mongoid::Timestamps::Created
  include Mongoid::Timestamps

  before_validation :auto_update_feild

  field :recommend_other_type, type: String
  #dynamic_fields Recommend::OtherColumn.where(:recommend_type => "index_foucus").entries

  def dynamic_attributes
    #update feild
    auto_update_feild

    #attr_hash = self.attributes
    attr_hash = self.attributes.clone
    attr_hash.delete_if { |attribute|
      self.fields.keys.member? attribute
    }
  end

  def other_columns
    Recommend::OtherColumn.where(:recommend_type => self.recommend_other_type).entries.first
  end

  def dynamic_attribute_names
    dynamic_attributes.keys
  end

  def dynamic_attribute_human(col = nil)
    if col.present? and other_columns.present?
      col_index = other_columns.column_names.index(col)
      human_name = other_columns.human_names.send("[]",col_index)
      if col_index.present? and human_name.present?
        human_name
      else
        col
      end
    end
  end

  def new
    if self.recommend_other_type.present? and other_columns.present?
      columns = other_columns.column_names
      if columns.present?
        #can not work
        #columns.collect{|col| self.send("[]=",col.to_sym,nil) unless self.fields.keys.include? col.to_s}
        columns.collect{|col| self.send("[]=",col.to_sym,nil) unless self.respond_to? col.to_s}
      end
      return self
    else
      super
    end
  end

  def auto_update_feild
    if self.recommend_other_type.present? and other_columns.present?
      columns = other_columns.column_names
      if columns.present?
        columns.collect{|col| self.send("[]=",col.to_sym,nil) unless self.respond_to? col.to_s}
      end
      return self
    end
  end

  def to_s
    "#{self.recommend_other_type}" if self.recommend_other_type.present?
  end
end

recommend_others_controller.rb

class Recommend::RecommendOthersController < ApplicationController
  load_and_authorize_resource  :class =>"Recommend::RecommendOther", :except => :update_field
  Model_class = Recommend::RecommendOther.new.class
  # GET /recommend/recommend_others
  # GET /recommend/recommend_others.json
  def index
    @recommend_recommend_others = Recommend::RecommendOther.all.desc(:recommend_other_type).entries

    breadcrumbs.add I18n.t("helpers.titles.#{current_action}", :model => Model_class.model_name.human), recommend_recommend_others_path

    respond_to do |format|
      format.html # index.html.erb
      format.json { render json: @recommend_recommend_others }
    end
  end

  # GET /recommend/recommend_others/1
  # GET /recommend/recommend_others/1.json
  def show
    @recommend_recommend_other = Recommend::RecommendOther.find(params[:id])

    breadcrumbs.add I18n.t("helpers.titles.#{current_action}", :model => Model_class.model_name.human), recommend_recommend_other_path(@recommend_recommend_other)

    respond_to do |format|
      format.html # show.html.erb
      format.json { render json: @recommend_recommend_other }
    end
  end

  # GET /recommend/recommend_others/new
  # GET /recommend/recommend_others/new.json
  def new
    @recommend_recommend_other = Recommend::RecommendOther.new

    breadcrumbs.add I18n.t("helpers.titles.#{current_action}", :model => Model_class.model_name.human), new_recommend_recommend_other_path

    respond_to do |format|
      format.html # new.html.erb
      format.json { render json: @recommend_recommend_other }
    end
  end

  # GET /recommend/recommend_others/1/edit
  def edit
    @recommend_recommend_other = Recommend::RecommendOther.find(params[:id])

    breadcrumbs.add I18n.t("helpers.titles.#{current_action}", :model => Model_class.model_name.human), edit_recommend_recommend_other_path(@recommend_recommend_other)
  end

  # POST /recommend/recommend_others
  # POST /recommend/recommend_others.json
  def create
    @recommend_recommend_other = Recommend::RecommendOther.new(params[:recommend_recommend_other])

    respond_to do |format|
      if @recommend_recommend_other.save
        format.html { redirect_to @recommend_recommend_other, notice: 'Recommend other was successfully created.' }
        format.json { render json: @recommend_recommend_other, status: :created, location: @recommend_recommend_other }
      else
        format.html { render action: "new" }
        format.json { render json: @recommend_recommend_other.errors, status: :unprocessable_entity }
      end
    end
  end

  def update_field
    recommend_other_type = params[:recommend_other_type]

    if recommend_other_type.present? and params[:recommend_other_id].present? and Recommend::RecommendOther.find(params[:recommend_other_id])
      @recommend_recommend_other = Recommend::RecommendOther.find(params[:recommend_other_id])
    end
    @recommend_recommend_other ||= Recommend::RecommendOther.new
    @recommend_recommend_other.recommend_other_type = recommend_other_type
    @recommend_recommend_other.auto_update_feild
  end

  # PUT /recommend/recommend_others/1
  # PUT /recommend/recommend_others/1.json
  def update
    @recommend_recommend_other = Recommend::RecommendOther.find(params[:id])

    respond_to do |format|
      if @recommend_recommend_other.update_attributes(params[:recommend_recommend_other])
        format.html { redirect_to @recommend_recommend_other, notice: 'Recommend other was successfully updated.' }
        format.json { head :no_content }
      else
        format.html { render action: "edit" }
        format.json { render json: @recommend_recommend_other.errors, status: :unprocessable_entity }
      end
    end
  end

  # DELETE /recommend/recommend_others/1
  # DELETE /recommend/recommend_others/1.json
  def destroy
    @recommend_recommend_other = Recommend::RecommendOther.find(params[:id])
    @recommend_recommend_other.destroy

    respond_to do |format|
      format.html { redirect_to recommend_recommend_others_url }
      format.json { head :no_content }
    end
  end
end

recommend_recommend_other.js

$(function($) {
  $("#recommend_recommend_other_recommend_other_type").live("change",function() {
    $.ajax({url: '/recommend/recommend_others/update_field',
    data : {
      recommend_other_type : this.value,
      recommend_other_id : $("#recommend_recommend_other_id").val()
    },
    dataType: 'script'})

  });
});

show.html.erb

<%- model_class = Recommend::RecommendOther.new.class -%>
  <h1><%=t '.title', :default => t('helpers.titles.show', :model => model_class.model_name.human,
                                 :default => "Show #{model_class.model_name.human}") %></h1>
<%= show_for @recommend_recommend_other do |s| %>
  <%= s.attribute :recommend_other_type %>
    <% dynamic_feilds = @recommend_recommend_other.dynamic_attribute_names %>
    <% if dynamic_feilds.present? %>
      <% dynamic_feilds.each do |dynamic_feild|%>
        <%= s.label @recommend_recommend_other.dynamic_attribute_human(dynamic_feild) %>
        <%= s.value dynamic_feild%>
      <% end %>
    <% end %>
  <%= s.attribute :created_at %>
  <%= s.attribute :updated_at %>
<% end %>

<% if can? :update, @recommend_recommend_other %>
  <%= link_to t('.edit', :default => t("helpers.links.edit", :model => model_class.model_name.human)), edit_recommend_recommend_other_path(@recommend_recommend_other), :class => 'btn' %> |
<% end %>
<% if can? :read, @recommend_recommend_other %>
  <%= link_to t('.back', :default => t("helpers.links.back", :model => model_class.model_name.human)), recommend_recommend_others_path, :class => 'btn' %> |
<% end %>
<% if can? :destroy, @recommend_recommend_other %>
  <%= link_to t('.destroy', :default => t("helpers.links.destroy", :model => model_class.model_name.human)), recommend_recommend_other_path(@recommend_recommend_other),
              :method => 'delete',
              :confirm => t('.confirm',
              :default => t("helpers.links.confirm", :default => 'Are you sure?')),
              :class => 'btn btn-danger' %>
<% end %>

update_field.js.erb

$("#recommend_recommend_other").replaceWith("<%= escape_javascript(render 'form') %>");