title: Extjs 4.0 store - how to find fields in the store (or model)
body: <p>In Ext 3.x I could get an array of field names with this:</p>
  
  <pre><code>mystore.fields.keys
  </code></pre>
  
  <p>How can I do this in 4.0?   I can't even see how I can get the model that the store is using (no 'getModel' method).  Do I need to find a record and get the fields that way?  I define the store with :</p>
  
  <pre><code>Ext.define('AM.store.Equipments', {
      extend: 'Ext.data.Store',
      model: 'AM.model.Equipment',
  
      mycustFunc: function () {
              var myfields = this.fields.keys  (fails!)
  </code></pre>
  
  <p>EDIT:
  Thanks... looking in firebug more it seems like this gets what I want:</p>
  
  <pre><code>this.model.prototype.fields.keys
  </code></pre>