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POAdding relationships with Has_Many Through. undefined local variable but everything works
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  1. POAdding relationships with Has_Many Through. undefined local variable but everything works
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    copied!<p>I've seen the undefined local variable in many threads, also I have seen adding relationships a lot, so please read the problem before suggesting it's answered elsewhere. (of course, if you do find an answer elsewhere, I will be just as grateful)</p> <p>The tables are <strong>Services</strong> and <strong>Checks</strong> (in the context of a garage, the service is the type and the checks are what need to be carried out for any particular service). This is many to many, so I've got a has many through relationship set up.</p> <p>The <strong>problem</strong> is, although everything is working fine, I am still getting the error:</p> <blockquote> <p>undefined local variable or method `check_ids'</p> </blockquote> <p>Line:</p> <pre><code>@service.service_checks.build(check_id: check_ids, service_id: @service.id ) </code></pre> <p>Any attempt I make to define the variable seems to stop the relationships from working. Which leaves me clueless as to how to get everything working in harmony.</p> <p>Models:</p> <pre><code>class Service &lt; ActiveRecord::Base has_many :service_checks, :dependent =&gt; :destroy has_many :checks, :through =&gt; :service_checks #attr_accessor :check_ids accepts_nested_attributes_for :checks accepts_nested_attributes_for :service_checks end class Check &lt; ActiveRecord::Base has_many :service_checks has_many :services, :through =&gt; :service_checks belongs_to :check_cat end class ServiceCheck &lt; ActiveRecord::Base belongs_to :service, dependent: :destroy belongs_to :check, dependent: :destroy accepts_nested_attributes_for :check, :reject_if =&gt; :all_blank self.primary_key = [:service_id, :check_id] end </code></pre> <p>My update function in Service looks like this:</p> <pre><code> def update respond_to do |format| if @service.update(service_params) # This builds the relationships @service.service_checks.build(check_id: check_ids, service_id: @service.id ) format.html { redirect_to @service, notice: 'Service was successfully updated.' } format.json { head :no_content } else format.html { render action: 'edit' } format.json { render json: @service.errors, status: :unprocessable_entity } end end end # Never trust parameters from the scary internet, only allow the white list through. def service_params params.require(:service).permit(:name, :price, :check_ids =&gt; []) end </code></pre> <p>And my form is simply:</p> <pre><code>&lt;%= f.association :checks, as: :check_boxes, label_method: :name, value_method: :id, label: 'Checks' %&gt; </code></pre>
 

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