title: Extjs - passing specific params thru ajax to another script
body: <p>I have a chart located in a panel. I want to pass the title of the panel to a php script using ajax.  I already use ajax proxy for my store. I would like to know the title of the panel so that I can query for the correct data, for example. Here's what I've done so far.</p>
  
  <pre><code>var store = Ext.create('Ext.data.JsonStore', {
      fields: ['project', 'accepted', 'rejected', 'deleted', 'undefined'],
      proxy: {
          type: 'ajax',
          url: 'generate_proj.php',
          extraParams: {foo: this.idname},
          reader: {
              type: 'json'
          }
      },
      autoLoad: true,
      listeners:  { 
          load: function(obj,records) {
              var text = Ext.decode(obj.responseText);
              console.log(this.idname);
              Ext.each(records,function(rec) {});
          }
      }
  });  
  </code></pre>
  
  <p>In my php script I use <code>$value = $_GET['foo'];</code>.</p>
  
  <p>I'm sure I'm close but I can't find any examples or documentation about how to take better advantage of params.  Any help or ideas?</p>