In the docs there is the following example which I modified a bit to check if data is loaded accordingly to model properties.

I used this code in the docs :http://ift.tt/1vCYp4J



Code:



Ext.define('myApp.Territory', {
    extend: 'Ext.data.TreeModel',
    fields: [{
        name: 'text',
        mapping: 'name'
    }]
});
Ext.define('myApp.Country', {
    extend: 'Ext.data.TreeModel',
    fields: [{
        name: 'text',
        mapping: 'name'
    }]
});
Ext.define('myApp.City', {
    extend: 'Ext.data.TreeModel',
    fields: [{
        name: 'text',
        mapping: 'name'
    }]
});
Ext.create('Ext.tree.Panel', {
    renderTo: document.body,
    height: 200,
    width: 400,
    title: 'Sales Areas - using typeProperty',
    rootVisible: false,
    store: {
        // Child types use namespace of store's model by default
        model: 'myApp.Territory',
        proxy: {
            type: 'memory',
            reader: {
                typeProperty: 'mtype'
            }
        },
        root: {
            children: [{
                name: 'Europe, ME, Africa',
                mtype: 'Territory',
                children: [{
                    name: 'UK of GB & NI',
                    mtype: 'Country',
                    children: [{
                        name: 'London',
                        mtype: 'City',
                        leaf: true
                    }]
                }]
            }, {
                name: 'North America',
                mtype: 'Territory',
                children: [{
                    name: 'USA',
                    mtype: 'Country',
                    children: [{
                        name: 'Redwood City',
                        mtype: 'City',
                        leaf: true
                    }]
                }]
            }]
        }
    }
});

and I changed mapping of Territory from 'name' into 'countryName'. All lower models with other types then read countryName property. So I guess the corresponding types are not loaded, reader falls back on default type myApp.Territory.

You need to provide namespace here in the data. Maybe this is not correct documented.