use NestedList tips "No items available"

view：

Code:

Ext.define('GS.view.BizTypeMenuView', {
        extend: 'Ext.NestedList',
    xtype: 'biztypemenuview',
        
    requires:['Ext.data.TreeStore'],


        
    config: {
        title: 'business',
                iconCls: 'home',
                displayField: 'text',
                store: {xclass:'GS.store.BizTypeStore'}
    }
});

Store：

Code:

Ext.define('GS.store.BizTypeStore', {
    extend: 'Ext.data.TreeStore',
    
    config: {
        model: 'GS.model.BizTypeModel',
        defaultRootProperty: 'items',
                root: {
                items: [
                    {
                        text: 'Drinks',
                        items: [
                            {
                                text: 'Water',
                                items: [
                                    { text: 'Still', leaf: true },
                                    { text: 'Sparkling', leaf: true }
                                ]
                            },
                            { text: 'Soda', leaf: true }
                        ]
                    },
                    {
                        text: 'Snacks',
                        items: [
                            { text: 'Nuts', leaf: true },
                            { text: 'Pretzels', leaf: true },
                            { text: 'Wasabi Peas', leaf: true  }
                        ]
                    }
                ]
            }
    }
});

Model：

Code:

Ext.define('GS.model.BizTypeModel', {
    extend: 'Ext.data.Model',
    config: {
        fields: [
                {name: 'text', type: 'string'}
        ]
    }
});

when i run this in chorme like this

_@~BD$Y(BDDPTKF2](4S.jpg

then i click one list ，it tips “No items availavle”

like this：3E(MW9YS}T5ST21@N1LCS.jpg

can anyone help me ？ I don't kown why this happend and how to resolve it