How to specify rootProperty for nested data if it is one level below?

问题

I am fetching nested data to be shown as nested list but whenever I tap on top level item, it again shows same top level list instead of showing children list and a ajax request is fired to fetch json data again. Here is the store:

Ext.define('MyTabApp.store.CategoriesStore',{
    extend:'Ext.data.TreeStore',
    config:{
        model   : 'MyTabApp.model.Category',
        autoLoad: false,
        storeId : 'categoriesStore',
        proxy: {
            type: 'ajax',
            url: 'resources/data/catTree.json',
            reader: {
                type: 'json',
                rootProperty: 'data.categories'
            }
        },
        listeners:{
            load: function( me, records, successful, operation, eOpts ){ 
                console.log("categories tree loaded");
                console.log(records);
            }
        }
    }
});

and here is the data in that file which I am using to mock service:

{
    "data":{
        "categories": [
            {
                "name": "Men",
                "categories": [
                    {
                        "name": "Footwear",
                        "categories": [
                            { "name": "Casual Shoes", "leaf": true },
                            { "name": "Sports Shoes", "leaf": true }
                        ]
                    },
                    {
                        "name": "Clothing",
                        "categories": [
                            { "name": "Casual Shirts", "leaf": true },
                            { "name": "Ethnic", "leaf": true }
                        ]
                    },
                    { "name": "Accessories", "leaf": true }
                ]
            },
            {
                "name": "Women",
                "categories": [
                    { "name": "Footwear", "leaf": true },
                    { "name": "Clothing", "leaf": true },
                    { "name": "Accessories", "leaf": true  }
                ]
            },
            {
                "name": "Kids",
                "categories": [
                    {
                        "name": "Footwear",
                        "categories": [
                            { "name": "Casual Shoes", "leaf": true },
                            { "name": "Sports Shoes", "leaf": true }
                        ]
                    },
                    { "name": "Clothing", "leaf": true }
                ]
            }
        ]
    }
}

This is the list:

Ext.define('MyTabApp.view.CategoriesList', {
    extend: 'Ext.dataview.NestedList',
    alias : 'widget.categorieslist',
    config: {
        height              : '100%',
        title               : 'Categories',
        displayField        : 'name',
        useTitleAsBackText  : true,
        style               : 'background-color:#999 !important; font-size:75%',
        styleHtmlContent    : true,
        listConfig: {
            itemHeight: 47,
            itemTpl : '<div class="nestedlist-item"><div>{name}</div></div>',
            height : "100%"
        }
    },
    initialize : function() {
        this.callParent();
        var me = this;

        var catStore = Ext.create('MyTabApp.store.CategoriesStore');
        catStore.load();
        me.setStore(catStore);
    }
});

The list starts working properly without any ajax request on each tap if I remove data wrapper over top categories array and change rootProperty to categories instead of data.categories. Since server is actually returning categories in data object I cannot remove it so how do I fix the store in that case? Also why is that additional ajax request to fetch the file?

[EDIT] Tried to create a fiddle http://www.senchafiddle.com/#d16kl which is similar but not same because it is using 2.0.1 and data is not loaded from external file or server.

回答1:

Last time I had this exact situation, it was because one of my top level category was a leaf but I had not set leaf:true. Doing so recalled the top level of the nested list as if it was a child.

回答2:

It seems from your Fiddle that if your data is in this following format, it would work fine:

{
  "categories" : [{
    "name" : "Foo",
    "categories" : [{
       ...
     }]
  }]
}

That is, just remove the "data" property and make defaultRootProperty: 'categories' & rootProperty: 'categories'. Check this: http://www.senchafiddle.com/#d16kl#tIhTp

It works with external data file as well.

来源：https://stackoverflow.com/questions/16854839/how-to-specify-rootproperty-for-nested-data-if-it-is-one-level-below