title: extjs4 paging grid reloading store on paging event
body: <p>i have a paging grid and some function that load a new store to the grid, but when i click on the next page it reverts back to the initial store</p>
  
  <p>the grid:</p>
  
  <pre class="lang-js prettyprint-override"><code>Ext.define('Pedido', {
      extend: 'Ext.data.Model',
      fields: [{
          name: 'ID',
          type: 'int'
      }, {
          name: 'Nome',
          type: 'string'
      }, {
          name: 'CPF/CNPJ',
          type: 'string'
      }, {
          name: 'Data',
          type: 'datetime'
      }, {
          name: 'TipoPagamento',
          type: 'string'
      }, {
          name: 'StatusPagamento',
          type: 'string'
      }, {
          name: 'TipoPagamento',
          type: 'string'
      }, {
          name: 'Total',
          type: 'string'
      }],
      idProperty: 'ID'
  });
  
  var store = Ext.create('Ext.data.Store', {
      pageSize: 10,
      model: 'Pedido',
      remoteSort: true,
      proxy: {
          type: 'ajax',
          url: 'http://localhost:4904/Pedido/ObterPedidosPorInquilino',
          reader: {
              root: 'Items',
              totalProperty: 'TotalItemCount'
          }
      }
  });
  
  var grid = Ext.create('Ext.grid.Panel', {
      id: 'grid',
      width: 500,
      height: 250,
      title: 'Array Grid',
      store: store,
  
      loadMask: true,
      viewConfig: {
          id: 'gv',
          trackOver: false,
          stripeRows: false
      },
      columns: [{
          id: 'gridid',
          text: "ID",
          dataIndex: 'ID',
          width: 50
      }],
      bbar: Ext.create('Ext.PagingToolbar', {
          store: store,
          displayInfo: true,
          displayMsg: 'Exibindo {0} - {1} de {2}',
          emptyMsg: "Nenhum pedido"
      }),
      renderTo: 'pedidos'
  });
  
  store.load({
      params: {
          start: 0,
          limit: 10
      }
  });
  </code></pre>
  
  <p>and the function that set the new store</p>
  
  <pre><code>store.load({
      params: {
          param: newparam
      }
  });
  </code></pre>
  
  <p>also, when I call this function, I would like to set the label on the viewing page x of y back to 1, since setting a new store takes you back to the first page</p>
  
  <p>thanks again</p>