为什么我下面的代码无法加载我的xml文件中的数据呢?

Ext.onReady(function(){

var dataStore = new Ext.data.Store({
proxy: new Ext.data.HttpProxy({url: 'sampledata-sheldon.xml'}),
reader: new Ext.data.XmlReader({
record: 'Item',
id: 'ASIN'
}, [
'Author', 'Title', 'Manufacturer', 'ProductGroup'
])
});

var colModel = new Ext.grid.ColumnModel([
        {header: "Author", width: 120, dataIndex: 'Author'},
            {header: "Title", width: 180, dataIndex: 'Title'},
            {header: "Manufacturer", width: 115, dataIndex: 'Manufacturer'},
            {header: "Product Group", width: 100, dataIndex: 'ProductGroup'}
]);

var grid = new Ext.grid.GridPanel({
    store: dataStore,
    cm: colModel,
    viewConfig: {
        forceFit:true
    },
    width: 600,
    height: 300,
    collapsible: true,
    animCollapse: false,
    title: 'test',
    iconCls: 'icon-grid',
    renderTo: document.body
});   

});

<?xml version="1.0" encoding="UTF-8"?>

            <Items>
                    <Request>
                            <IsValid>True</IsValid>
                            <ItemSearchRequest>
                                    <Author>Sidney Sheldon</Author>
                                    <SearchIndex>Books</SearchIndex>
                            </ItemSearchRequest>
                    </Request>
                    <TotalResults>203</TotalResults>
                    <TotalPages>21</TotalPages>
                    <Item>
                            <ASIN>0446357448</ASIN>
                            <DetailPageURL>http://www.amazon.com/gp/<;/DetailPageURL>
                            <ItemAttributes>
                                    <Author>Sidney Sheldon</Author>
                                    <Title>Bloodline</Title>
                                    <Manufacturer>Warner Books</Manufacturer>
                                    <ProductGroup>Book</ProductGroup>
                            </ItemAttributes>
                    </Item>
            </Items>
    </ItemSearchResponse>

仔细看了下.好像没有设置store的加载呀,
你执行dataStore.load();
或者配置store的autoLoad:true 即可

你的xml文件有问题啊

<?xml version="1.0" encoding="UTF-8"?>

            <Items> 
                    <Request> 
                            <IsValid>True</IsValid> 
                            <ItemSearchRequest> 
                                    <Author>Sidney Sheldon</Author> 
                                    <SearchIndex>Books</SearchIndex> 
                            </ItemSearchRequest> 
                    </Request> 
                    <TotalResults>203</TotalResults> 
                    <TotalPages>21</TotalPages> 
                    <Item> 
                            <ASIN>0446357448</ASIN> 
                            <DetailPageURL>http://www.amazon.com/gp/<;/DetailPageURL> 
                            <ItemAttributes> 
                                    <Author>Sidney Sheldon</Author> 
                                    <Title>Bloodline</Title> 
                                    <Manufacturer>Warner Books</Manufacturer> 
                                    <ProductGroup>Book</ProductGroup> 
                            </ItemAttributes> 
                    </Item> 
            </Items> 
    </ItemSearchResponse> 

去掉这行[color=red][/color]