title: How to set multiple value in select box using grails
body: <p>I am using grails 2.1.1. I have a table named audit firm. There are two types of firm. Audit review firm and ca firm. I am saving the value of audit review firm in parent table and ca firm in child table that's why ca firm is a multiple select box. But when I want to edit the audit review firm is selected but ca firms are not selected in the multiple select box. I have searched for it and applied some things but no luck. Can anyone please help me on this please ??!!! Here are my attempts below ::</p>
  
  <p>my parent domain >>></p>
  
  <pre><code>    class DistrictAssignToAuditReviewFirm {
      static mapping = {
          table('ADT_DIST_ASSN_TO_ADT_RV_FIRM')
          version(false)
  
          caFirm cascade: 'all'
      }
  
      AuditFirm auditReviewFirm
  
      long CREATED_BY=0
      Date CREATED_DATE=new Date()
      long UPDATED_BY=0
      Date UPDATED_DATE=new Date()
  
      static hasMany = [caFirm: DistrictAssignToAuditReviewFirmDetails]
  
  
      static constraints = {
          auditReviewFirm(nullable: false, blank: false)
  
          CREATED_BY(nullable:true)
          CREATED_DATE(nullable:true)
          UPDATED_BY(nullable: true)
          UPDATED_DATE(nullable: true)
      }
      String toString(){
          return auditReviewFirm
      }
  }
  </code></pre>
  
  <p>my child domain >>></p>
  
  <pre><code>    class DistrictAssignToAuditReviewFirmDetails {
      static mapping = {
          table('ADT_DIST_ASSN_TO_ADT_RV_DETL')
          version(false)
      }
  
      AuditFirm caFirmDetails
      DistrictAssignToAuditReviewFirm distAssnToAdtRevFirm
  
      static constraints = {
          caFirmDetails(nullable: false, blank: false)
          distAssnToAdtRevFirm(nullable: false, blank: false)
      }
      String toString(){
          return caFirmDetails
      }
  }
  </code></pre>
  
  <p>my view page >>></p>
  
  <pre><code>    &lt;div class="col-xs-6"&gt;
      &lt;div class="form-group"&gt;
          &lt;label for="auditReviewFirm"&gt;
              &lt;g:message code="dl" default="Audit Review Firm" /&gt;
          &lt;/label&gt;
          &lt;g:select id="auditReviewFirm" name="auditReviewFirm.id" from="${auditReviewFirm}" optionValue="auditFirmName" optionKey="id" noSelection="['':'Select One']" required="" value="${districtAssignToAuditReviewFirmInstance?.auditReviewFirm?.id}" class="form-control"/&gt;
      &lt;/div&gt;
  &lt;/div&gt;
  
  &lt;div class="col-xs-6"&gt;
      &lt;div class="form-group"&gt;
          &lt;label for="caFirm"&gt;
              &lt;g:message code="dl" default="CA Firm" /&gt;
          &lt;/label&gt;
          &lt;g:select id="caFirm" name="caFirm.id" from="${caFirm}" optionValue="auditFirmName" optionKey="id" multiple="true" required="" value="${districtAssignToAuditReviewFirmInstance?.caFirm?.caFirmDetails?.id}" class="form-control"/&gt;
      &lt;/div&gt;
  &lt;/div&gt;
  </code></pre>