This is the code create by the Architect 2.1.0
Panel:
Code:
Ext.define('MyApp.view.MyPanel', {
    extend: 'Ext.panel.Panel',

    frame: true,
    height: 443,
    width: 614,
    layout: {
        align: 'stretch',
        type: 'vbox'
    },
    title: 'My Panel',

    initComponent: function() {
        var me = this;

        Ext.applyIf(me, {
            items: [
                {
                    xtype: 'gridpanel',
                    autoShow: false,
                    height: 245,
                    stateId: 'Grid',
                    title: 'My Grid Panel',
                    store: 'MyXmlStore',
                    viewConfig: {
                        frame: true
                    },
                    columns: [
                        {
                            xtype: 'gridcolumn',
                            dataIndex: 'Marca',
                            text: 'Marca'
                        },
                        {
                            xtype: 'gridcolumn',
                            dataIndex: 'Modello',
                            text: 'Modello'
                        },
                        {
                            xtype: 'gridcolumn',
                            dataIndex: 'Targa',
                            text: 'Targa'
                        },
                        {
                            xtype: 'booleancolumn',
                            dataIndex: 'Disponibile',
                            text: 'Disponibile'
                        },
                        {
                            xtype: 'numbercolumn',
                            dataIndex: 'Limite_Km',
                            text: 'Limite_Km'
                        },
                        {
                            xtype: 'numbercolumn',
                            dataIndex: 'Priorita',
                            text: 'Priorita'
                        }
                    ]
                },
                {
                    xtype: 'panel',
                    flex: 1,
                    title: 'My Panel'
                }
            ]
        });

        me.callParent(arguments);
    }

});
Store:
Code:
Ext.define('MyApp.store.MyXmlStore', {
    extend: 'Ext.data.Store',

    requires: [
        'MyApp.model.MyModel'
    ],

    constructor: function(cfg) {
        var me = this;
        cfg = cfg || {};
        me.callParent([Ext.apply({
            autoLoad: true,
            filterOnLoad: false,
            storeId: 'MyXmlStore',
            model: 'MyApp.model.MyModel',
            clearOnPageLoad: false,
            clearRemovedOnLoad: false,
            proxy: {
                type: 'ajax',
                url: 'http://localhost/Auto.xml',
                reader: {
                    type: 'xml',
                    root: 'dataroot',
                    record: 'Auto'
                }
            }
        }, cfg)]);
    }
});
Models:
Code:
Ext.define('MyApp.model.MyModel', {
    extend: 'Ext.data.Model',

    fields: [
        {
            name: 'Marca',
            type: 'string'
        },
        {
            name: 'Modello',
            type: 'string'
        },
        {
            name: 'Targa',
            type: 'string'
        },
        {
            name: 'Disponibile',
            type: 'boolean'
        },
        {
            name: 'Limite_Km',
            type: 'int'
        },
        {
            name: 'Priorita',
            type: 'int'
        }
    ]
});
File XML:
Code:
<?xml version="1.0" encoding="UTF-8"?> 
<dataroot xmlns:od="urn:schemas-microsoft-com:officedata" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  xsi:noNamespaceSchemaLocation="Auto.xsd" generated="2012-12-07T22:44:11"> 
<Auto> 
<Marca>BMW</Marca> 
<Modello>135</Modello> 
<Targa>bf444rt</Targa> 
<Disponibile>1</Disponibile> 
<Limite_Km>200</Limite_Km> 
<Priorita>3</Priorita> 
</Auto> 
<Auto> 
<Marca>BMW</Marca> 
<Modello>Serie 4</Modello> 
<Targa>fd435tr</Targa> 
<Disponibile>1</Disponibile> 
<Limite_Km>180</Limite_Km> 
<Priorita>2</Priorita> 
</Auto> 
<Auto> 
<Marca>Fiat</Marca> 
<Modello>Stilo</Modello> 
<Targa>gr567yt</Targa> 
<Disponibile>1</Disponibile> 
<Limite_Km>450</Limite_Km> 
<Priorita>2</Priorita> 
</Auto> 
<Auto> 
<Marca>Fiat</Marca> 
<Modello>Stilo</Modello> 
<Targa>hg876jy</Targa> 
<Disponibile>0</Disponibile> 
<Limite_Km>450</Limite_Km> 
<Priorita>2</Priorita> 
</Auto> 
<Auto> 
<Marca>Fiat</Marca> 
<Modello>Stilo</Modello> 
<Targa>ku876rt</Targa> 
<Disponibile>0</Disponibile> 
<Limite_Km>400</Limite_Km> 
<Priorita>1</Priorita> 
</Auto> 
<Auto> 
<Marca>Fiat</Marca> 
<Modello>Panda</Modello> 
<Targa>gf457jy</Targa> 
<Disponibile>1</Disponibile> 
<Limite_Km>350</Limite_Km> 
<Priorita>2</Priorita> 
</Auto> 
<Auto> 
<Marca>Fiat</Marca> 
<Modello>Panda</Modello> 
<Targa>ng876jy</Targa> 
<Disponibile>0</Disponibile> 
<Limite_Km>320</Limite_Km> 
<Priorita>1</Priorita> 
</Auto> 
<Auto> 
<Marca>Ford</Marca> 
<Modello>Focus</Modello> 
<Targa>vb453rt</Targa> 
<Disponibile>1</Disponibile> 
<Limite_Km>320</Limite_Km> 
<Priorita>3</Priorita> 
</Auto> 
<Auto> 
<Marca>Ford</Marca> 
<Modello>Focus</Modello> 
<Targa>ht567yu</Targa> 
<Disponibile>1</Disponibile> 
<Limite_Km>280</Limite_Km> 
<Priorita>2</Priorita> 
</Auto> 
<Auto> 
<Marca>Ford</Marca> 
<Modello>Focus</Modello> 
<Targa>nb778hg</Targa> 
<Disponibile>1</Disponibile> 
<Limite_Km>280</Limite_Km> 
<Priorita>2</Priorita> 
</Auto> 
<Auto> 
<Marca>Ford</Marca> 
<Modello>Fiesta</Modello> 
<Targa>fr453rt</Targa> 
<Disponibile>1</Disponibile> 
<Limite_Km>350</Limite_Km> 
<Priorita>1</Priorita> 
</Auto> 
<Auto> 
<Marca>Ford</Marca> 
<Modello>Fiesta</Modello> 
<Targa>bt675ht</Targa> 
<Disponibile>1</Disponibile> 
<Limite_Km>400</Limite_Km> 
<Priorita>2</Priorita> 
</Auto> 
<Auto> 
<Marca>Ford</Marca> 
<Modello>Ka</Modello> 
<Targa>vc453gt</Targa> 
<Disponibile>1</Disponibile> 
<Limite_Km>240</Limite_Km> 
<Priorita>2</Priorita> 
</Auto> 
<Auto> 
<Marca>Volkswagen</Marca> 
<Modello>Golf</Modello> 
<Targa>nb654tr</Targa> 
<Disponibile>1</Disponibile> 
<Limite_Km>450</Limite_Km> 
<Priorita>2</Priorita> 
</Auto> 
<Auto> 
<Marca>Volkswagen</Marca> 
<Modello>Passat</Modello> 
<Targa>gf343tr</Targa> 
<Disponibile>1</Disponibile> 
<Limite_Km>700</Limite_Km> 
<Priorita>3</Priorita> 
</Auto> 
<Auto> 
<Marca>Volkswagen</Marca> 
<Modello>Polo</Modello> 
<Targa>nh676ht</Targa> 
<Disponibile>0</Disponibile> 
<Limite_Km>300</Limite_Km> 
<Priorita>1</Priorita> 
</Auto> 
</dataroot>
The XML is at the url: localhost/Auto.xml
Someone can say me where are the errors?
I'm trying to learn this language but is so difficult as the beginning...
sorry for my english