Events on fields

var shows = Ext.create('Ext.data.Store', {
    fields: ['id','show'],
    data: [
        {id: 0, show: 'Battlestar Galactica'},
        {id: 1, show: 'Doctor Who'},
        {id: 2, show: 'Farscape'},
        {id: 3, show: 'Firefly'},
        {id: 4, show: 'Star Trek'},
        {id: 5, show: 'Star Wars: Christmas Special'}
    ]
});

Ext.create('Ext.form.Panel', {
    renderTo: Ext.getBody(),
    title: 'Sci-Fi Television',
    height: 200,
    width: 500,
    items: [{
        xtype: 'tagfield',
        fieldLabel: 'Select a Show',
        store: shows,
        displayField: 'show',
        valueField: 'id',
        queryMode: 'local',
        filterPickList: true,
        listeners: {
            change: {
                fn: function(){ console.log('Fiddle Change!')}
            },
            expand: {
                fn: function(){ console.log('Fiddle expand!')}
            },
            collapse: {
                fn: function(){ console.log('Fiddle collapse!')}
            }
        }
    }]
});