title: How to add paging to extjs 4 grid?
body: <p>I have a store like this which i used for a extjs grid</p>
  
  <pre><code>Ext.create('Ext.data.Store', {
      autoLoad : true,
      fields   : [
          {name: 'item_code', mapping: 'item_code', type: 'string'},
          {name: 'quantity', mapping: 'quantity', type: 'string'},
          {name: 'description', mapping: 'description', type: 'string'},
          {name: 'selling_price', mapping: 'selling_price', type: 'string'},
          {name: 'discount', mapping: 'discount', type: 'string'}
      ],
      storeId  : 'available_products',
      proxy    : {
          type            : 'ajax',
          actionMethods   : 'POST',
          url             : 'http://192.168.1.6/transactions/distribution_store',
          reader: {
              type: 'json',
              root: 'data'
          }
      }
  });
  </code></pre>
  
  <p>I want to add a paging to grid but i want it like this</p>
  
  <p>first load all the data with json and paging those results at client side without sending server requests.</p>
  
  <p>is it possible?
  how to do this?</p>
  
  <p>Regards</p>