title: odoo many2many show selection Odoo10
body: <p>we have a list of items in one model named us_inventory_line. We have another model named ladings... </p>
  
  <pre class="lang-py prettyprint-override"><code>class inventory_line(models.Model):
      # ...
      lading_item = fields.Many2one('res.lading', ondelete='set null', string="lading", index=True)
  
  class Lading(models.Model):
      # ... 
      us_inventory_line_item = fields.One2many(comodel_name='rodals.us_inventory_line', string="shippments", inverse_name='lading_item')
  </code></pre>
  
  <p>In the form, we have just simply put the field that represent one2many:</p>
  
   <pre class="lang-xml prettyprint-override"><code>&lt;!-- Form --&gt;
  &lt;record model="ir.ui.view" id="us_inventory_line_form_view"&gt;
      &lt;field name="name"&gt;lading.form&lt;/field&gt;
      &lt;field name="model"&gt;rodals.lading&lt;/field&gt;
      &lt;field name="arch" type="xml"&gt;
          &lt;form string="Invetory Line Form"&gt;
              &lt;sheet&gt;
                  &lt;group&gt;
                      &lt;field name="delivery_date"/&gt;
                      &lt;field name="us_inventory_line_item"/&gt;
                  &lt;/group&gt;
              &lt;/sheet&gt;
          &lt;/form&gt;
      &lt;/field&gt;
  &lt;/record&gt;
  </code></pre>
  
  <p>When the application is opened, when the user opens the lading page, he is only able to add new us_inventory_line.  </p>
  
  <p>How do we go about in order to connect the tow ? Like the user need to choose, from a list of us_inventory_line that does not have a lading (because if its has lading, this means that its already shipped).</p>
  
  <p>Thank you very much for the help !</p>