title: How can I resolve error 'ext-all.js Uncaught TypeError: Cannot call method 'getProxy' of undefined' ?
body: <p>I tried to use ExtJS with a JSON database but I keep getting the same error: <code>ext-all.js Uncaught TypeError: Cannot call method 'getProxy' of undefined</code>.</p>
  
  <p>My script is :</p>
  
  <pre><code> Ext.onReady(function(
      var store=new Ext.data.Store( 
        reader=new Ext.data.JsonReader(        
                              {name: 'name'},
              {name: 'category' },
              {name: 'address'},                   
              {name: 'lat'},
              {name: 'long'},
                              {name: 'tel'},
                              {name: 'opening'},
              {name: 'closing'}),
                  proxy=new Ext.data.HttpProxy({
              url : 'http://localhost/progetto/descrittore/json.php'}))
              // method : 'GET'
            })
  </code></pre>
  
  <p>In my HTML I included :</p>
  
  <pre><code>&lt;script type="text/javascript" src="extjs/ext-all.js"&gt;&lt;/script&gt;
  &lt;script type="text/javascript" src="extjs/prova.js"&gt;&lt;/script&gt;
  </code></pre>
  
  <p>What's causing this error, and how can I resolve it?</p>