title: Odoo 12: How to use form values in @api.model methods
body: <p>I am new in the forum.<br>
  I am currently working with Odoo 12 and I'm having some problems communicating Odoo Model with my Javascript Widget. Step by step...<br>
  1. I am creating a widget that shows some Google Charts and the only way I've found was to show the QWeb code in a custom view and assign the Widget to a Char field.<br>
  2. I've achieved a nice approach using rpc in my start: function using rpc and getting the data from the module.<br>
  3. THE PROBLEM:<br>
  I need to show two Date fields in the form and use that dates as an interval for my Google Charts: How can I get the date values in my @api.model<br>
   function??<br>
  The function can only read a resultset of all the table, when I try to get the result (self.init_date) set in the field, I always receive "False"<br>
  Sorry, I can't post the code today, but on Monday I will post it if nobody can give me the answer.<br>
  Thank you very much!</p>