Ext JS Cycle through items of a Ext.form.CheckboxGroup

I have a Ext.form.CheckboxGroup with multiple items of Ext.form.Checkbox.

Is it possi开发者_JAVA技巧ble to cycle through each item of the Ext.form.CheckboxGroup?

I have tried the following to no avail:

for ( var i in Ext.getCmp('product_category_group').items.items) {
    console.log(i.getId());
}

Any advice appreciated, thanks.

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This works for me : (ExtJs 3.2)

Ext.getCmp('product_category_group').items.each(function(i) {
   console.log(i.getId());
})