ExtJS 4 Grid Update

Sorry if this is a stupid question, but I'm trying to learn ExtJS ;)

Im create model.

Ext.regModel('item',{

Create data store.

var store = Ext.create('Ext.data.Store', {
        model: 'pitem',

Create Grid

var grid = new Ext.grid.GridPanel({
        store: store,

Work good and load data on document load succcessful. But now I ne开发者_开发知识库ed to update grid every 30 minutes or by clicking the refresh button. How can I execute the update action?

The part with upgrading store every 30 minutes :

var task = 
{
   run : function() 
   {
      store.load();
   },
   interval: 1800000 //(1 second = 1000)
}

Ext.TaskManager.start(task);

To reload the data of your Store, just call store.load().

you can load data directly using store.loadData() function.