VERY SIMPLE ViewModel, WEIRD behavior

Hi guys,

I have found at a really WEIRD behavior about view models, in particular stores of viewmodels.

I have a fiddle that describe the problem here: http://ift.tt/1uerqnU

But to sum up:

1 - I define a view model class with a store inside it like this

Code:

Ext.define('TestViewModel', {
    extend: 'Ext.app.ViewModel',

    alias: 'viewmodel.myviewmodel', 

    stores: {
        simpsonsStore: Ext.create('Ext.data.Store', {
            fields:['name', 'email', 'phone'],
            data:[
                {'name': 'Lisa',  "email":"lisa@simpsons.com", "phone":"555-111-1224"},
                {'name': 'Bart',  "email":"bart@simpsons.com", "phone":"555-222-1234"},
                {'name': 'Homer', "email":"homer@simpsons.com", "phone":"555-222-1244"},
                {'name': 'Marge', "email":"marge@simpsons.com", "phone":"555-222-1254"}
            ]
        })
    }
});

2 - I have defined a view (grid) bound to the viewmodel that I have defined. The vie is using the store of the view model:

Code:

Ext.define('TestSimpsonsGrid', {
    extend: 'Ext.grid.Panel',
    title: 'Simpsons',
    height: 200,
    width: 400,
    
    viewModel: {
        type: 'myviewmodel'
    },
    
    bind: '{simpsonsStore}',
    columns: [
        { text: 'Name',  dataIndex: 'name' },
        { text: 'Email', dataIndex: 'email', flex: 1 },
        { text: 'Phone', dataIndex: 'phone' }
    ]
});

3 - I create two views (two simpson grids):

Code:

var grid1 = Ext.create('TestSimpsonsGrid', {
    renderTo: Ext.getBody()
});


var grid2 = Ext.create('TestSimpsonsGrid', {
    renderTo: Ext.getBody()
});

4 - I create a button which, when clicked, will change the store data of the first grid viewmodel:

Code:

var button = Ext.create('Ext.Button', {
    text: 'Click to change the first grid viewmodel\'s store',
    renderTo: Ext.getBody(),
    margin: '10 10 10 63',
    
    handler: function() {
        grid1.getViewModel().getStore('simpsonsStore').loadData([{
            "name": "Michel",  "email":"michel@simpsons.com",  "phone":"666-111-1224"
        }]);
    }
});

5 - Even if the views (grids) have two different viewmodels they share the same simpsonStore, and both grid are changed when I click on the button.

Is this the expected behavior ??

Thanks in advance !

VERY SIMPLE ViewModel, WEIRD behavior